Abu Dhabi, United Arab Emirates. STANDARD CONSTRUCTION SPECIFICATIONS (PART 2 - ROAD STRUCTURES, 2020)

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-46

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

23.6.9

Steel Structure Connections Using High-strength Bolts

This section covers the assembly of structural joints using AASHTO M 164-05 (ASTM A325 - 10) or
AASHTO M 253-05 (ASTM A490

– 12) high-strength bolts or equivalent fasteners, installed so as to

develop the minimum required bolt tension specified in Table 23-10. The bolts are used in holes
conforming to the requirements of Section 23.5.5.

The Contractor shall tighten (ASTM A325

– 10) bolts in accordance with the procedures specified

herein for turn-of-nut or direct-tension-indicator (DTI) tightening.

When the Engineer approves (ASTM A307

– 10) bolts for use in miscellaneous components, tighten

them such that the plies of the joint are in firm contact. Use three to five impacts of an impact wrench
or the full effort of a person using an ordinary spud wrench to obtain a snug connection.

Lubricate and maintain consistency in lubrication of fastener assembly during Rotational Capacity
(RC) testing and installation. Assemblies that exhibit a loss of lubrication, as determined by the
Engineer, may be relubricated and retested before installation.

Fasten aluminum, other materials or assemblies of dissimilar materials in accordance with the
Contract documents.

Install ordinary rough or machine bolts and nuts in accordance with the Contract documents.

23.6.9.1

Bolted Parts of Steel Structures

All material within the grip of the bolt shall be steel; there shall be no compressible material such as
gaskets or insulation within the grip. Bolted steel parts shall fit solidly together after the bolts are
snugged and may be coated or uncoated. The slope of the surfaces of parts in contact with the bolt
head or nut shall not exceed 1:20 with respect to a plane normal to the bolt axis.

23.6.9.2

Surface Conditions for High-strength Bolts

At the time of assembly, all joint surfaces, including surfaces adjacent to the bolt head and nut, shall
be free of scale, except tight mill scale, and shall be free of dirt or other foreign material. Burrs that
would prevent solid seating of the connected parts in the snug condition shall be removed.

Paint is permitted on the faying surface including slip critical joints when designed in accordance
with Article 6.13.2, "Bolted Connections," of the

AASHTO LRFD Bridge Design Specifications

Contacting surfaces of slip-critical connections shall meet the requirements of the following
paragraphs, as applicable:

a. In non-coated joints, paint, including any inadvertent overspray, shall be excluded from areas

closer than one bolt diameter but not less than 25 mm from the edge of any hole and all areas
within the bolt pattern.

b. Joints specified to have painted faying surfaces shall be blast cleaned and coated with a

paint which has been qualified in accordance with requirements of Article 6.13.2.8, "Slip
Resistance," of the AASHTO LRFD Bridge Design Specifications.

c. Coated joints shall not be assembled before the coating has cured for the minimum time used

in the qualifying test.

Faying surfaces specified to be galvanized shall be hot-dip galvanized in accordance with AASHTO
M 111M/M 111-11 (ASTM A123 / A123M - 12). The Contractor shall provide certification to the
Engineer that galvanized faying surfaces meet or exceed a Class C slip critical classification, unless
a different classification is required elsewhere in the Contract documents. The Contractor shall
mechanically roughen the galvanized faying surfaces by means of hand wire brushing. Power wire
brushing is not permitted.

"Surface conditions" refers to Article 6.13.2, "Bolted Connections," and Article 6.13.2.8, "Slip
Resistance," of the AASHTO LRFD Bridge Design Specifications.

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-47

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

23.6.9.3

Reaming for High-strength Bolts

The Contractor shall not over size bolt holes by reaming (or any other method) without the approval
of the Engineer.

23.6.9.4

Drifting for High-strength Bolts

The Contractor shall not over size, stretch, or otherwise damage bolt holes by improper and
excessive drifting.

23.6.9.5

Filler Material for Splice Plate

Unless otherwise specified in the Contract documents, the Contractor shall provide filler material
edges within 3 mm of the adjacent splice material edge.

23.6.9.6

Installing High-strength Fasteners

Fastener  components  shall  be  assigned  lot  numbers,  including  rotational-capacity  lot  numbers,
before  shipping  and  components  shall  be  assembled  when  installed.  Such  components  shall  be
protected from dirt and moisture at the job site. Only the number of anticipated components to be
installed and tensioned during a work shift shall be removed from protective storage. Components
not used shall be returned to protective storage at the end of the shift. Assemblies for slip-critical
connections  which  accumulate  rust  or  dirt  resulting  from  job  site  conditions  shall  be  cleaned,
relubricated,  and  tested  for  rotational  capacity  before  installation.  All  galvanized  nuts  shall  be
lubricated with a lubricant containing a visible dye. Plain bolts must be oily to touch when delivered
and installed. Lubricant on exposed surfaces shall be removed before painting.

A bolt-tension measuring device (a Skidmore-Wilhelm Calibrator or other equivalent bolt-tension
indicating device) shall be at all job sites wherever final connections are being made. The Contractor
shall confirm the accuracy of the tension measuring device by having it calibrated by an approved
testing agency once a year. The tension-measuring device shall be used to perform the rotational-
capacity test and to confirm:

a. The suitability to satisfy the requirements of Table 23-10 of the complete fastener assembly,

including lubrication if required to be used in the work

b. calibration of the wrenches, and
c. the understanding and proper use by the bolting crew of the installation method.

To perform the calibrated wrench verification test for short grip bolts, direct tension indicators (DTI)
with solid plates may be used in lieu of a tension-measuring device. The DTI lot shall be first verified
with a longer grip bolt in the Skidmore-Wilhelm Calibrator or an acceptable equivalent device. The
frequency of confirmation testing, the number of tests to be performed, and the test procedure shall
be as specified in this section, as applicable. The accuracy of the tension measuring device shall be
confirmed by an approved testing agency at least annually.

Bolts and nuts together with washers of size and quality specified in the Contract documents, located
as required below, shall be installed in properly aligned holes and tensioned and inspected by any
of the installation methods described in this section to at least the minimum tension specified in Table
23-10. Tensioning may be done by turning the bolt while the nut is prevented from rotating. When it
is impractical to turn the nut, impact wrenches, if used, shall be of adequate capacity and sufficiently
supplied with air to apply the proper tension to each bolt in approximately ten seconds.

Bolts shall be installed in all holes of the connection and the connection brought to a snug condition.

Unless shown otherwise in the Erection Plan, the Contractor shall install the bolts of the connection
by progressing systematically from the most rigid part of the connection to the free edges. Install
bolts in all holes of the connection and bring them to a ‘snug tight’ condition. Following the sequence
indicated in the Erection Plan, further tighten all the bolts in the connection until the full connection
is in a snug condition.

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-48

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

For connections (such as large main load-carrying members or truss joints) in which previously
tightened high strength bolts become loose and require retightening upon the tensioning of others,
install into a minimum of ten percent of the holes fully tensioned bolts before final tensioning of the
permanent bolts. Distribute these first bolts randomly throughout the connection. If directed by the
Engineer, remove the initial bolts and install permanent bolts at each location, otherwise retighten in
accordance with this section.

Table 23-10: Minimum required bolt tension

Bolt size

AASHTO M 164-05

ASTM A325 - 10

AASHTO M 253-05

ASTM A490

– 12

13 mm

53.5 kN

66.7 kN

16 mm

84.5 Kn

106.8 kN

19 mm

124.6 kN

155.7 kN

22 mm

173.5 kN

218.0 kN

25 mm

227.0 kN

284.7 kN

29 mm

249.0 kN

356.0 kN

32 mm

316.0 kN

453.7 kN

35 mm

378.0 kN

538.2 kN

38 mm

458.0 kN

658.3 kN

Minimum bolt tension shall be taken as seventy percent (70%) of specified minimum tensile strength
of bolts (as specified in ASTM Specifications for tests of full-size A325 and A490 bolts with UNC
threads (

Metric Screw Threads: M Profile

, ANSI ASME B1.13M-2005), loaded in axial tension)

rounded to the nearest 1000 N. Table 23-11 shows necessary rotations.

Table 23-11: Nut rotation from snug condition

Geometry of outer faces of bolted parts

Bolt length (from
underside of head to
end of bolt)

Both faces
normal

bolt axis

One face normal to bolt axis
and other face sloped not
more

than

1:20

(Bevel

washer not used)

Both faces sloped not more
than 1:20 from normal to
bolt axis (Bevel washers not
used)

Up to and including
4 diametres

1/3 turn

1/2 turn

2/3 turn

Over  4  diametres,
but  not  exceeding  8
diametres

1/2 turn

2/3 turn

5/6 turn

Over 8 diametres,
but not exceeding
12 diametres

2/3 turn

5/6 turn

1 turn

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-49

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

Rotation, as used in Table 23-11, shall be taken as relative to the bolt, regardless of the element
(nut or bolt) being turned. The tolerances are minus 0, plus 30 degrees for bolts installed by a 1/2
turn or less; for bolts installed by 2/3 turn or more, the tolerance are minus 0, plus 45 degrees.

Values given in Table 23-11 shall be applicable only to connections in which all material within grip
of the bolt is steel.

For situations in which the bolt length measured from the underside of the head to the end of the
bolt exceeds 12 diameters, the required rotation shall be determined by actual tests in a suitable
tension device simulating the actual conditions. Submit procedures to the Engineer for review.

Rotational Capacity Tests

At the location of and before installation of permanent high-strength fasteners in main or primary
load carrying member connections, the Contractor shall perform rotational capacity (RC) tests to
ensure that the fasteners are capable of developing the specified strength and that the fasteners are
properly lubricated. As a minimum, the Contractor shall test two assemblies per LOT designation.
The bolt, nut and washer shall come from the same LOT and be packed in the same container (or
group of containers assigned the same LOT), except in special cases where nuts and washers have
only one production LOT number for each size.

Assemblies specified as galvanized shall be tested after galvanising. Washers are required for RC
tests even though they may not be required for jobsite installation. Where washers are not required
for jobsite installation, LOT identification is not required. The washer coating shall be the same as
that for the bolt and nut. The following shall apply:

1. Except as modified herein, the rotational-capacity test shall be performed in accordance with

the requirements of AASHTO M 164-05 (ASTM A325 - 10).

2. Perform the RC test in a manner that replicates the anticipated fastener installation technique

(that is, if a spud wrench is to be used as a part of the installation process, use the wrench
similarly for the RC test).

3. If any of the required tests fails, the entire LOT will be rejected.
4. Each combination of bolt production lot, nut lot, and washer lot shall be tested as an

assembly.

5.  A rotational-capacity lot number shall have been assigned to each combination of lots tested.
6.  Minimum frequency of testing shall be two assemblies per rotational-capacity lot.
7.  For  bolts  that  are  long  enough  to  fit  in  a  Skidmore-Wilhelm  Calibrator,  the  bolt,  nut,  and

washer assembly shall be assembled in a Skidmore- Wilhelm Calibrator or an acceptable
equivalent device.

8. Bolts that are too short to test in a Skidmore-Wilhelm Calibrator may be tested in a steel joint.

The tension requirement, in the section below, need not apply. The maximum torque
requirement, torque ≤ 0.250PD, shall be computed using a value of P equal to the turn test
tension taken as 1.15 times the bolt tension in Table 23-7.

9. Tension reached at the rotation below, i.e., the turn-test tension, shall be equal to or greater

than 1.15 times the required fastener tension, i.e., installation tension, shown in Table 23-10.

10. In a tension-measuring device, the minimum rotation from an initial tension of ten percent of

the minimum required tension shall be two times the required number of turns indicated in
Table 23-11 without stripping or failure.

After the required installation tension listed above has been exceeded, one reading of tension and
torque shall be taken and recorded. The torque value shall conform to Equation 23-9.

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-50

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

Torque ≤ 0.250 P D

Equation 23-9: Torque for rotational capacity testing

Where:

Torque

measured torque, N.mm.

P =

measured bolt tension,

D =

bolt diametre, mm.

Requirement for Washers for Installation with High-strength Fasteners

The Contractor shall provide ASTM F436 - 11 hardened steel washers as follows:

1. For connections (and all associated testing) using (ASTM A490

– 12) bolts, use a hardened

washer under each element.

2. For connections using (ASTM A325

– 10) bolts, use hardened washers under the turned

element.

3. Use hardened steel washers as part of the Rotational Capacity tests.
4. Where the outer face of the bolted parts has a slope of greater than 1:20 with respect to a

plane normal to the bolt axis, use a hardened, beveled washer to compensate for the lack of
parallelism.

5. Where bolts are to be installed in a oversized or slotted hole in an outer ply, provide a single

washer satisfying ASTM F436 - 11, or continuous bar satisfying ASTM A709 / A709M

– 11.

For (ASTM A325

– 10) bolts, provide a thickness of at least 8mm; and for (ASTM A490 – 12)

bolts, provide a thickness of 10mm. Provide these washers or bars to completely cover the
slot after installation. Provide a finish consistent with the bolt specified.

6. In non-Direct-Tension-Indicator (DTI) applications, clip washers on one side to a point not

closer than 22mm of the bolt diametre from the center of the washer, if necessary.

7. Hardened bevelled washers for American Standard Beams and Channels shall be required

and shall be square or rectangular, shall conform to the requirements of AASHTO M 293-10
(ASTM F436 - 11), and shall taper in thickness.

8. Where necessary, washers may be clipped on one side to a point not closer than 0.875 times

the bolt diametre from the center of the washer.

Use of Washers with Direct-tension-indicators (DTIs) Devices

When DTIs are used; the Contractor shall use ASTM F436 - 11 hardened washers as follows:

1. When the nut is turned and the DTI is located under the bolt head, a hardened washer is to

be located under the nut.

2. When the nut is turned and the DTI is located under the nut, a hardened washer is to be

located between the nut and the DTI.

3. When the bolt head is turned and the DTI is located under the nut, a hardened washer is to

be located under the bolt head.

4. When the bolt head is turned and the DTI is located under the bolt head, a hardened washer

is to be located between the bolt head and the DTI.

Hardened Washers for Installation with High-strength Fasteners

Hardened washers are not required for connections using AASHTO M 164-05 (ASTM A325 - 10)
and AASHTO M 253-05 (ASTM A490

– 12) bolts, except as follows:

1. Hardened washers shall be used under the turned element when tensioning is to be

performed by calibrated wrench method.

2. Irrespective of the tensioning method, hardened washers shall be used under both the head

and the nut when AASHTO M 253-05 (ASTM A490

– 12) bolts are to be installed in material

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-51

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

having a specified yield point less than 275 MPa. When DTIs are used, they may replace a
hardened washer provided a standard sized hole is used.

3. Where AASHTO M 164-05 (ASTM A325 - 10) bolts of any diametre or AASHTO M 253-05

(ASTM A490

– 12) bolts equal to or less than 24 mm in diametre are to be installed in oversize

or short-slotted holes in an outer ply, a hardened washer conforming to AASHTO M 293-10
(ASTM F436 - 11) shall be used.

4. Where AASHTO M 253-05 (ASTM A490

– 12) bolts over 24 mm in diametre are to be

installed in an oversize or short-slotted hole in an outer ply, hardened washers conforming to
AASHTO M 293-10 (ASTM F436 - 11), except with 8 mm minimum thickness, shall be used
under both the head and the nut in lieu of standard thickness hardened washers. Multiple
hardened washers with combined thickness equal to or greater than 8 mm shall not be
considered as satisfying this requirement.

5. Where AASHTO M 164-05 (ASTM A325 - 10) bolts of any diametre or AASHTO M 253-05

(ASTM A490

– 12) bolts equal to or less than 24 mm in diametre are to be installed in a long

slotted hole in an outer ply, a plate washer or continuous bar of at least 8 mm thickness with
standard holes shall be provided. These washers or bars shall have a size sufficient to
completely cover the slot after installation and shall be of structural grade material, but need
not be hardened, except as follows.

6. Where AASHTO M 253-05 (ASTM A490

– 12) bolts over 24 mm in diametre are to be used

in long slotted holes in external plies, a single hardened washer conforming to AASHTO M
293-10 (ASTM F436 - 11), but with 8 mm minimum thickness shall be used in lieu of washers
or bars of structural grade material. Multiple hardened washers with combined thickness
equal to or greater than 8 mm shall not be considered as satisfying this requirement.

Alternate High-strength Fasteners

As an alternative, the Contractor may use high-strength fasteners that comply with the requirements
outlined in Article 23.4.2.5. Such fasteners shall have a geometry that provides a bearing circle on
the head or nut with a diametre equal to or greater than the diametre of hardened washers that meet
the requirements of AASHTO M 293-10 (ASTM F436 - 11) and satisfy the requirements for washers
outlined in this chapter. The Contractor may use such fasteners without washers.

Turn-of Nut Installation Method for High-strength Fasteners

When the turn-of-nut installation method is used, hardened washers are not required, except as may
be specified in Article 23.6.9.6.

For  each  work  shift,  the  Contractor  shall  perform  tests  utilizing  a  representative  sample  of  five
fastener assemblies, from each LOT to  be installed that shift. Perform the tests using the tension
measuring  device,  following the  same  procedure  to  be  used for  actual  installation  of the fastener
assemblies,  to  a  snug-tight  tension  and  corresponding  torque,  which,  when  the  additional  turns
required in Table 23-11, Nut Rotation from the Snug Condition are added, will result in at least 1.05
times the minimum required fastener installation tension as shown in Table 23-10. Place a washer
under the part turned in the tightening of the bolt. Consider the job inspection snug-tight torque as
the  average  of three  test  values  determined  after rejecting the  high  and  low-test  values.  Periodic
retesting shall be performed when ordered by the Engineer.

After snugging, the applicable amount of rotation specified in Table 23-11 shall be achieved. During
the tensioning operation there shall be no rotation of the part not turned by the wrench. Tensioning
shall progress systematically from the most rigid part of the joint to its free edges.

Snug-tight Condition:

In the turn-of-nut method, first bring all the fastener assemblies of the

connection to a ‘snug-tight’ condition to ensure that all parts of the connection are in firm contact with
each other. For the purposes of this specification, “firm contact” shall mean the condition that exists
on a faying surface when the plies are solidly seated against each other, but not necessarily in
continuous contact. Regard snug-tight as the tightness required to produce the bolt tension, which
following the final applied rotation, produces at least 1.05 times the minimum required bolt tension

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-52

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

in accordance with Table 20.8. In the presence of the Engineer, and on a daily basis, determine the
job inspection snug-tight torque as specified herein.

Final Tightening:

After verification of the snug-tight condition in accordance with Article 23.6.9.6 by

the Engineer, the Contractor shall tighten all fastener assemblies in the joint by applying the
applicable amount of nut rotation specified in Table 23-11. Once snug-tight, bring all fasteners to the
required tension within the same work shift.

Calibrated Wrench Installation Method for High-strength Fasteners

A calibrated wrench method may be used only when wrenches are calibrated on a daily basis and
when a hardened washer is used under the turned element. Standard torques determined from
tables or from formulas which are assumed to relate torque to tension shall not be acceptable.

When calibrated wrenches are used for installation, they shall be set to deliver a torque which has
been calibrated to produce a tension not less than five percent in excess of the minimum tension
specified in Table 23-10. The installation procedures shall be calibrated by verification testing at least
once each working day for each fastener assembly that is being installed in the work that day. This
verification testing shall be accomplished in a tension-measuring device capable of indicating actual
bolt  tension  by  testing  three  typical  fastener  assemblies  from  each  lot.  Bolts,  nuts,  and  washers
under  the  turned  element  shall  be  sampled  from  production  lots.  Wrenches  shall  be  recalibrated
when a significant difference is noted in the surface condition of the bolts, threads, nuts, or washers.
It shall be verified during actual installation in the assembled steel work that the wrench adjustment
selected by the calibration does not produce a nut or bolt head rotation from snug condition greater
than that permitted in Table 23-11. If manual torque wrenches are used, nuts shall be torqued in the
tensioning direction when torque is measured.

When calibrated wrenches are used to install and tension bolts in a connection, bolts shall be
installed with hardened washers under the turned element. Following snugging, the connection shall
be tensioned using the calibrated wrench. Tensioning shall progress systematically from the most
rigid part of the joint to its free edges. The wrench shall be returned to "touch up" previously tensioned
bolts which may have been relaxed as a result of the subsequent tensioning of adjacent bolts until
all bolts are tensioned to the prescribed amount.

Alternative Design Bolt Installation Method for High-strength Fasteners

When fasteners which incorporate a design feature intended to indirectly indicate that the applied
torque develops the required bolt tension or to automatically develop the tension required by Table
23-10 and that have been qualified under Article 23.4.2.4 are to be installed, verification testing using
a representative sample of not less than three fastener assemblies of each diametre, length and
grade to be used in the work shall be performed at the job site in a device capable of indicating bolt
tension. The test assembly shall include flat-hardened washers, if required in the actual connection,
arranged as in the actual connections to be tensioned. The verification test shall demonstrate that
each bolt develops a tension not less than five percent greater than the tension required by Table
23-10. The Manufacturer's installation procedure shall be followed for installation of bolts in the
calibration device and in all connections. Periodic retesting shall be performed when ordered by the
Engineer.

When  alternative  design  fasteners,  which  are  intended  to  control  or  indicate  bolt  tension  of  the
fasteners  are  used,  bolts  shall  be  installed  in  all  holes  of  the  connection  and  initially  snugged
sufficiently to bring all plies of the joint into firm contact, but without yielding or fracturing the control
or  indicator  element  of  the  fasteners.  All  fasteners  shall  then  be  further  tensioned,  progressing
systematically  from  the  most  rigid  part  of  the  connection  to  the  free  edges  in  a  manner  that  will
minimize relaxation of previously tensioned bolts. In some cases, proper tensioning of the bolts may
require more than a single cycle of systematic partial tensioning before final yielding or fracturing of
the control or indicator element of individual fasteners. If yielding or fracture occurs before the final
tensioning cycle, the individual fastener assembly shall be replaced with a new one.

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-53

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

Direct Tension Indicator Installation Method for High-strength Fasteners

Every day, when installing direct tension indicator (DTI) devices that meet the requirements of Article
23.4.2.5 in accordance with the method specified below, the Contractor shall perform the DTI
verification tests described below at the location of installation.

Unless otherwise approved by the Engineer, the DTIs shall be installed under the head of the bolt
and the nut turned to tension the bolt. The Manufacturer's recommendations shall be followed for
the proper orientation of the DTI and additional washers, if any, required for the correct use of the
DTI. Installation of a DTI under the turned element may be permitted if a washer is used to separate
the turned element from the DTI.

The Contractor shall perform DTI verification test on a minimum of two high-strength fastener
assemblies from each fastener assembly LOT and position of the DTI before production installation.
If either assembly fails, test additional fastener assembly LOT/DTI combinations as requested by the
Engineer to verify that the Requirements of the Contract documents have been satisfied. These two
tests are in addition to the RC tests required in Article 23.6.9.6. If, after additional testing, the DTI
fails to meet the requirements of these specifications, the LOT will be rejected by the Engineer.

Verification of Direct Tension Indicator Installation

Verification testing shall be performed in a calibrated bolt-tension measuring device. A special flat
insert shall be used in place of the normal bolt head holding insert. Three verification tests shall be
required for each combination of fastener assembly rotational-capacity lot, DTI lot, and DTI position
relative to the turned element (bolt head or nut) to be used on the project. The fastener assembly
shall be installed in the tension-measuring device with the DTI located in the same position as in the
work. The element intended to be stationary (bolt or nut) shall be restrained from rotation.

The  verification  tests  shall  be  conducted  in  two  stages.  The  bolt  nut  and  DTI  assembly  shall  be
installed in a manner so that at least three and preferably not more than five threads are located
between the bearing face of the nut and the bolt head. The bolt shall be tensioned first to the load
equal to that listed in Table 23-10 under Verification Tension for the grade and diameter of the bolt.
If an impact wrench is used, the tension developed using the impact wrench shall be no more than
two-  thirds  of  the  required  tension.  Subsequently,  a  manual  wrench  shall  be  used  to  attain  the
required tension. The number of refusals of the 0.125 mm tapered feeler gage in the spaces between
the protrusions shall be recorded. The number of refusals for uncoated DTIs under the stationary or
turned  element,  or  coated  DTIs  under the stationary  element, shall  not  exceed  the  number  listed
under Maximum Verification Refusals in Table 23-12 for the grade and diameter of bolt used. The
maximum  number  of  verification  refusals  for  coated  DTIs  (galvanized,  painted,  or  epoxy-coated),
when used under the turned element, shall be no more than the number of spaces on the DTI less
one. The DTI lot shall be rejected if the number of refusals exceeds the values in the table or, for
coated DTIs if the gage is refused in all spaces.

After the number of refusals is recorded at the verification load, the bolt shall be further tensioned
until the 0.125 mm feeler gage is refused at all the spaces and a visible gap exists in at least one
space. The load at this condition shall be recorded and the bolt removed from the tension-measuring
device. The nut shall be able to be run down by hand for the complete thread length of the bolt
excluding thread run-out. If the nut cannot be run down for this thread length, the DTI lot shall be
rejected unless the load recorded is less than 95 percent of the average load measured in the
rotational capacity test of the fastener lot as specified in Article 23.6.9.6, "Rotational-Capacity Tests".

If the bolt is too short to be tested in the calibration device, the DTI lot shall be verified on a long bolt
in a calibrator to determine the number of refusals at the verification tension listed in Table 23-12. A
number of refusals shall not exceed the values listed under maximum verification refusals in Table
23-12. Another DTI from the same lot shall then be verified with the short bolt in a convenient hole
in the work. A bolt shall be tensioned until the 0.125 mm feeler gage is refused in all spaces and a
visible gap exists in at least one space. A bolt shall then be removed from the tension-measuring
device and the nut shall be able to be run down by hand for the complete thread length of the bolt
excluding thread run-out. A DTI lot shall be rejected if the nut cannot be run down this thread length.

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-54

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

Table 23-12: Direct tension indicator requirements

Bolt
size

Verification
tension

Maximum verification
refusals

DTI spaces

Minimum installation
refusals

A325

A490

A325

A490

A325 A490 A325

A490

13 mm 57.8 kN 71.2 kN

16 mm 89.0 kN

111.2
kN

19 mm

129.0
kN

164.6
kN

22 mm

182.4
kN

227.0
kN

25 mm

240.2
kN

298.0
kN

29 mm

262.4
kN

373.7
kN

32 mm

333.6
kN

476.0
kN

35 mm

396.0
kN

564.0
kN

38 mm

480.4
kN

689.5
kN

Installation of Fastener Assemblies with Direct Tension Indicator Devices

Installation of fastener assemblies using DTI devices shall be performed in two stages. A stationary
element shall be held against rotation during each stage of the installation. A connection shall be
first snugged with bolts installed in all the holes of the connection and tensioned sufficiently to bring
all the plies of the connection into firm contact. A number of spaces in which a 0.125 mm feeler gage
is refused in the DTI after snugging shall not exceed those listed under Maximum Verification
Refusals in Table 23-12. If the number exceeds the values in the table, the fastener assembly shall
be removed and another DTI installed and snugged.

For uncoated DTIs used under a stationary or turned element and for coated DTIs used under
stationary element, the bolts shall be further tensioned until the number of refusals of the 0.125 mm
feeler gage shall be equal to or greater than the number listed under Minimum Installation Refusals
in Table 23-12. If the bolt is tensioned so that no visible gap in any space remains, the bolt and DTI
shall be removed and replaced by a new properly tensioned bolt and DTI.

When coated DTIs (galvanized, painted, or epoxy coated) are used under a turned element, the
0.125 mm feeler gage shall be refused in all spaces.

Reusing and Retightening High-strength Fasteners

The Contractor shall not reuse (ASTM A490

– 12) bolts or galvanized (ASTM A325 – 10) bolts. Black

(ASTM A325

– 10) bolts with free spinning nuts may be reused one time with the Engineer’s

approval. Previously tightened bolts that may have been loosened by the tightening of adjacent bolts

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-55

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

can be further tightened from the original position. The Contractor shall ensure proper lubrication
before retightening, discard and replace fractured or damaged bolts.

m. Installing Lock-pin and Collar Fasteners

Installation of lock-pin and collar fasteners shall be by methods and procedures approved by the
Engineer.

Inspecting Installation of High-strength Fasteners

The Engineer shall determine that the following requirements of this Sub-article are met in the work.
Before the installation of fasteners in the work, the Engineer shall:

1. check the marking, surface condition, and storage of bolts, nuts, washers, and DTIs, if used,

and the faying surfaces of joints for compliance with the requirements of Sections 23.4.2 and
23.6.9, and Article 23.6.9.6 and

2. observe calibration and/or testing procedures required in Article 23.6.9.6, as applicable, to

confirm that the selected procedure is properly used and that, when so used with the fastener
assemblies supplied, the tensions specified in Table 23-10 are developed.

The Engineer shall monitor the installation of fasteners in the work to assure that the selected
installation method, as demonstrated in the initial testing to develop the specified tension, is routinely
followed.

Procedures to Inspect Installation of High-strength Fasteners

Either the Engineer or the Contractor, in the presence of the Engineer at the Engineer's option, shall
inspect the tensioned bolts using an inspection torque wrench, unless alternate fasteners or direct
tension indicator devices are used, allowing verification by other methods. Inspection tests should
be conducted before possible loss of lubrication or corrosion influence on tightening torque.

Three fastener assembly lots in the same condition as those under inspection shall be placed
individually in a device calibrated to measure bolt tension. This calibration operation shall be done
at least once each inspection day.

There shall be a washer under the turned element in tensioning each bolt if washers are used on the
structure. If washers are not used on the structure, the material used in the tension-measuring device
which abuts the part turned shall be of the same specification as that used on the structure. In the
calibrated device, each bolt shall be tensioning by any convenient means to the specified tension.
The inspecting wrench shall then be applied to the tensioned bolt to determine the torque required
to turn the nut or head five degrees (25 mm at a 300 mm radius) in the tensioning direction. The
average of the torque required for all three bolts shall be taken as the job-inspection torque.

Turn-of-nut Tightening for High-strength Fasteners

Turn-of-nut tightening for high-strength fasteners shall meet the following requirements.

1. Once the snug-tight condition is achieved for all of the fastener assemblies of the connection,

within 24 hours of snugging the first bolt in the connection and in the presence of the
Engineer, the Contractor shall verify for a minimum of three (3) bolts [two (2) for two bolt
connections] or 10% of the fastener assemblies, that the job inspection snug-tight torque has
been attained. These fasteners are to have a snug-tight torque equal to or exceeding that
specified in 23.6.9.6. Perform this check using the same torque wrench used in 23.6.9.6.

2. If the tested fasteners do not obtain the job inspection snug-tight torque, test all remaining

untested fastener assemblies using the torque wrench in the connection in question.
Following testing of all assemblies, bring to snug-tight all assemblies and retest as stated
above. Resnug and retest as necessary using the calibrated torque wrench until the minimum
testing stated above is performed favorably.

3. Following confirmation of the snug-tight condition as performed by the Contractor, and in the

presence of the Engineer, match mark the fastener assemblies on the end of the bolt thread

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-56

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

and on the nut, and then tighten the nut the amount of rotation specified in Table 23-11. The
Engineer will accept the connection as fully tightened when all of the following conditions are
met:

•

Rotation specified in Table 23-11 has been achieved

•

There are no loose assemblies in the connection

•

All plies of the connection are in firm contact

•

There are no indications that excessive stretching or yielding has occurred in the

fastener assembly

•

Bolt stick-through is consistent per lot

Direct Tension Indicator Tightening for High-strength Fasteners

Before bringing the connection to a snug-tight condition, the Contractor shall verify in the presence
of the Engineer that the

‘dimples’ of the DTI are not deformed or damaged. Bring the connection to

a snug-tight condition and tighten in accordance with the requirements of Article 23.6.9.6. The
Engineer will accept the connection as fully tightened when all of the following conditions are met:

1.  the requirements of Article 23.6.9.6 have been achieved
2.  there are no loose assemblies in the connection
3.  all plies of the connection are in firm contact
4.  there  are  no  indications  that  excessive  stretching  or  yielding  has  occurred  in  the  fastener

assembly

5. Bolt stick-through is consistent per lot

23.6.10

Welding for Steel Structures

Except as noted in the Contract documents, shop and field welding, welder qualifications,
prequalification of weld details, and inspection of welds shall conform to the requirements of the
current AASHTO/AWS D1.5M/D1.5:2010,

Bridge Welding Code

Brackets, clips, shipping devices, or other material not required by the Contract documents shall not
be welded or tacked to any member unless specified in the Contract documents and approved by
the Engineer.

Additional or alternate requirements for hollow steel structural sections and non-dynamically loaded
members or components are listed below.

Welding shall be a metal arc process in accordance with BS EN 1011-2:2001 and BS EN 1011-
8:2004, as appropriate, together with other clauses contained in this section, unless otherwise
specifically permitted by the Engineer.

Welding consumables used shall be chosen to ensure that the mechanical properties of the weld
metal are not less than those required for the parent metal.

Joints shall be prepared in accordance with BS EN 1011-2:2001. Precautions shall be taken to
ensure cleanliness of the connection prior to welding.

23.6.10.1 Welding on Non-dynamically Loaded Elements

The  Contractor  shall  perform  welding  on  miscellaneous  components  and  other  statically  (non-
dynamically,  noncyclically,  etc.)  loaded  structural  elements  in  accordance  with  the  AWS  D1.1,
Structural Welding  Code,  or  the  AASHTO/AWS  D1.5M/D1.5:2010,

Bridge Welding Code

. Unless

otherwise specified in the Contract documents or as approved by the Engineer, follow the Bridge
Welding Code for weld inspection and welder certifications.

23.6.10.2 Electroslag Welding

The Contractor shall use Narrow-Gap Improved Electroslag Welding (NGI-ESW) for joining non-
fracture critical members or components up to 75mm thick. These members or components may be
subjected to tension, compression or stress reversal. Inspect 100% of all NGI-ESW welds subject to

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-57

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

tension stresses or reversal of stress by both UT (ultrasonic examination as described in Section 6,
Part C of the AASHTO/AWS D1.5M/D1.5:2010,

Bridge Welding Code

) and RT (radiographic

examination as described in Section 6, Part B of the AASHTO/AWS D1.5M/D1.5:2010,

Bridge

Welding Code

Perform NGI-ESW welding in accordance with the AASHTO/AWS D1.5M/D1.5:2010,

Bridge

Welding Code

. Supplemented by the recommendations from the following references:

•

Report No. FHWA-SA-96-

053, “Technical Information Guide for Narrow.Gap Improved

Electroslag Welding

”.

•

Report No. FHWA-SA-96-

052, “Process Operational Guide for Narrow-Gap Improved

Electroslag Welding

”.

23.6.10.3 Welding of Hollow Structural Steel Sections (Pipes and Tubes)

Except as noted in the Contract documents, the Contractor shall perform all shop and field welding
of Hollow Structural Shapes in accordance with the ANSI/AWS D1.1/D1.1M:2010, Structural Welding
Code

– Steel, as amended herein.

Welding Highway Signs, Luminaires and Traffic Signals

For structural steel sign structures, lighting poles, and traffic signal poles, the Contractor shall comply
with the additional requirements of AASHTO

Standard Specification for Structural Steel Supports for

Highway Signs, Luminaires and Traffic Signals

Edition

, Section 1.4.2, Welding of Steel

Structures.

Welding Bridge Structures

For tubular bridge structures including pedestrian bridges, the Contractor shall comply with the
requirements of the ANSI/AWS D1.1/D1.1M:2010,

Structural Welding Code

– Steel,

as amended by

the following:

1. Qualify all welding processes in accordance with the AASHTO/AWS D1.5M/D1.5:2010,

Bridge Welding Code

. Comply with all qualification criteria including production thickness and

position limitations. Use ASTM A709 / A709M - 11 Grade 50 for this test.

2. UT NDE technicians performing inspection of TKY welds are to be qualified to the

requirements and recommendations for operator qualification specified in API RP 2X:2004,

Recommended practice for ultrasonic and magnetic examination of offshore structural
fabrication and guidelines for qualification of technicians, 4th Edition

, including a practical

test with mockup tubular welds containing built-in flaws.

3. Perform nondestructive testing of all tubular complete joint penetration groove welds in main

members using Ultrasonic Testing in accordance with the ANSI/AWS D1.1/D1.1M:2010,

Structural Welding Code

– Steel

Perform ultrasonic testing at the following frequency:

•

One hundred percent of each joint subject to tension or reversal of stress.

•

Twenty-five percent of each joint subject to compression or shear.

If unacceptable discontinuities are found in the joint, the remainder of the joint shall be tested.

Perform Magnetic Particle Testing on 300mm in every 3.0 metre on each fillet and partial penetration
groove welds in main members but no less than 300mm on welds less than 3.0 metre.

23.6.10.4 Non-destructive Testing of Welds

Record of Testing

The test results shall be recorded and be available for inspection by the Engineer.

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-58

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

Visual Inspection of Welds

Visual inspection shall be made in accordance with guidance given in BS EN ISO 17637:2011 over
the full length of the weld and before NDT inspection is performed. Any welds which will be rendered
inaccessible by subsequent work shall be examined in prior to the loss of access.

A suitably qualified person for visual inspection of welds may be a welding inspector or a welder who
can provide evidence of having been trained and assessed for competence in visual inspection of
the relevant types of welds.

Surface Flaw Detection

Where a closer examination of a weld surface is required, magnetic particle inspection (MPI) shall
be used in accordance with the recommendations given in BS EN ISO 9934-1:2001.

If magnetic particle inspection equipment is not available, dye penetrant inspection (DPI) may be
used in accordance with the recommendations given in BS EN ISO 3452-1:2013.

Final surface flaw detection of a welded joint shall be carried out not less than 16 hours from the
time of completion of the weld to be inspected, or not less than 40 hours in the case of welds to
Design Grade 55 material. The Contractor shall note that where a welding procedure requires an
inspection after initial weld runs before further welding is performed, such inspections may be carried
out when the weld metal has cooled to ambient temperature.

A suitably qualified person for surface flaw detection of welds may be a welding inspector or a welder
who holds a current certificate of competence in surface flaw detection of the relevant types of work,
from a recognised authority.

Ultrasonic Examination

Where ultrasonic examination is required, it shall be made in accordance with BS EN ISO
17640:2010, Level 2B. Examination shall be carried out not less than 16 hours from the time of
completion of the weld to be inspected, or not less than 40 hours in the case of butt welds thicker
than 40 mm or any welds to Design Grade 55 material.

Operators carrying out final ultrasonic examination of the weld shall hold a current certificate of
competence from a recognised authority.

23.6.10.5 Field Welding

The Contractor shall field weld only with the approval of the Engineer. Provide any additional field
welding procedures as requested by the Engineer for review.

23.6.10.6 Tack Welding

The Contractor shall not weld or tack any fill plates, brackets, clips, shipping devices, or other
materials not required by the Contract documents or allowed by the AASHTO/AWS
D1.5M/D1.5:2010,

Bridge Welding Code

1. Tack welds shall be made using the same procedures as for the root runs of main welds. The

length of the tack shall be the lesser of 4 times the thickness of the thicker part or 50 mm,
unless demonstrated by a weld procedure qualification.

2. Tack welds which are not defective may be incorporated into main welds provided that the

welder is qualified as in Article 23.4.11.3 of this chapter. However, where joints are welded
using an automatic or mechanised process, the suitability of the tack weld used for
incorporation into automatic processes shall be demonstrated in the weld procedure
qualification.

3. Where tack welds are made in circumstances other than those identified above, they must

be removed.

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-59

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

23.7

Erecting Steel Structures

The Contractor shall provide all tools, machinery, and equipment necessary to erect the structure.

Falsework and forms shall be in accordance with the requirements of Section 1.20.8 of Chapter 1,
General Requirements.

23.7.1

Pre-erection Requirements

The Contractor shall complete all of the requirements outlined in this section before erecting the steel
structure for the Project.

23.7.1.1

Quality Control Plan for Erecting Steel Structures

Develop an Erection Quality Control Plan for review and approval of the Engineer.

23.7.1.2

Submittals for Erecting Steel Structures

The Contractor shall provide submittals to the Engineer for review in accordance with the Contract
documents.

23.7.1.3

Plan for Erecting Steel Structures

The Contractor shall submit, for the Engineer

’s review, an Erection Plan locating all primary

members,  lifting  equipment  and  temporary  supports  or  braces,  and  bolting  pattern  tightening
procedures not considered routine. Ensure that the plan are signed and stamped by  Professional
Engineer.  Include  supporting  calculations  indicating  that  the  design  unit  stresses  indicated  in  the
Contract  documents  have  not  been  exceeded.  Provide  this  Plan  or  Plans  to  the  Engineer  three
weeks before erecting the piece or pieces.

The following information shall be included in the Erection Plan:

a. A plan of the work area showing all substructure units and foundations; surface roads and

railroads; all streams, creeks and rivers; and all overhead and underground utilities.

b. The erection sequence for all primary load-carrying members and all primary load-carrying

member bracing. Note any and all permanent or temporary support and/or bracing locations,
including crane-holding positions.

c. The center of gravity locations, pick weight and delivery orientation for all primary load-

carrying members and pick weight.

d.  Identify any bolting requirements not considered routine.
e.  Locate all pick crane work points.
f.  Identify  all  temporary  works  and  staging  areas  such  as  barges,  mats  and  temporary

excavation support.

g. Provide capacity charts on the drawings for each crane configuration and boom extension

utilized.

h. Details of all temporary bracing, falsework, towers and shoring.
i. Provide any procedures requested by the Engineer and not contained in the Quality Control

Plan.

23.7.2

Special Requirements to Resist Steel Weathering

The Contractor shall not use marking materials (grease sticks, crayons) that leave behind a residual
film that may affect the weathering process of the steel. Store the girders as required for non-
weathering steels.

23.7.2.1

Preparing Steel Against Weathering

Before erection, the Contractor shall perform the following as appropriate:

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-60

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

Blast clean the exposed fascia of the exterior girders (both I and box) to meet criteria of SSPC-SP
10/NACE No. 2,

Near-White Blast Cleaning

; blast clean the remaining exposed surfaces of steel

trapezoidal girders, not required to be prepared otherwise, to meet criteria of SSPC-SP 6/NACE No.
3,

Commercial Blast Cleaning

; for steel I-girders, if a non-uniform mill scale finish has developed, as

determined by the Engineer, blast clean all remaining exposed surfaces, not required to be prepared
otherwise, to an SSPC-SP 6/NACE No. 3 criteria; coat the inside of box members including, but not
limited to, all bracing members, cross frames and diaphragms with only the prime coat. For the
bottom or walking surface, certify that the applicable OSHA requirements on slip resistance will be
obtained after applying the coating. Reapply the coating as necessary to satisfy the OSHA
requirements. Submit the composition of coating to the Engineer for review.

23.7.2.2

Preparing a Concrete Substructure Against Weathering

Before erection of the girders, the Contractor shall wrap all exposed substructure concrete surfaces
with polyethylene sheeting, or equal, as approved by the Engineer, to protect them against staining
from  the  weathering  steel  components.  Leave  the  sheeting  in  place  and  keep  it  free  of  tears  or
separations until just before the preparation for and application of the Class 5 Finish. In any case,
do not remove the sheeting  before placement of the concrete deck. As directed by the  Engineer,
clean all visible stains on concrete in areas not receiving a Class 5 Finish by sandblasting and follow-
on  cleaning  using  a  stain  remover  or  commercial  cleaner  after  completion  of  the  structure  in
accordance  with  Chapter  4,  Concrete  Works,  of  these  standard  specifications,  and  Chapter  21,
Concrete Structures.

23.7.2.3

Structure and Site Clean Up after Weather Protection

Upon the completion of construction, the Contractor shall remove all oil, dirt, grease or other foreign
material, including excessive or uneven mill scale from the steel. Remove lubricants from the
exposed surfaces of installed fastener assemblies and other surfaces in accordance with the
Manufacturer

’s recommendations. Final surface finish is to be an even mill scale as approved by the

Engineer.

23.7.3

Aligning Steel Structure with Substructure

Before the erection of primary load-carrying members, the Contractor shall conduct a survey to
document the vertical, longitudinal and transverse position of all substructure units and anchor rod
locations. Appropriately account for ambient temperature in the survey.

Should a discrepancy be identified with the Contract documents, the Contractor shall submit the
necessary details to the Engineer for resolution.

23.7.4

Placing Anchor Rods for Erection of Steel Structure

The Contractor shall locate and place anchor rods within the tolerance shown in the Contract
documents or within 6mm of the theoretical location shown. If anchor rods cannot be located to the
specified tolerance, place only with the approval of the Engineer. Unless shown otherwise in the
Contract documents, provide galvanized anchor rods, nuts and washers as follows:

1.  Set the anchor rods in preformed holes vertical to the plane of the bridge seat.
2.  Provide 100mm diametre holes.
3.  Provide non-shrink grout/mortar of a strength greater than or equal to that of the substructure

concrete strength, or as shown elsewhere in the Contract documents.

4. Install the rods in accordance with the grout/mortar Manufacturer

’s recommendations.

5. Clean the threads of the anchor rods as necessary without damaging the coating.

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-61

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

23.7.5

Preparing Bearing Areas and Setting Bearings for Erection of
Steel Structure

Before placing superstructure bearing units (including but not limited to neoprene pads and masonry
plates), the Contractor shall prepare the top of concrete pad (bearing area) in accordance with
Section 21.10.4 of Chapters 21, Concrete Structures, and Chapter 25, Bearing Devices. If a
discrepancy is identified, report it to the Engineer for resolution.

For expansion bearings with slotted holes for anchor rods, which allow movement of the
superstructure with respect to the substructure, the Contractor shall vary the location of the slotted
plate in relation to the anchor rods, in accordance with the prevailing temperature at the time of
setting. For fixed bearings at multiple adjacent piers, if necessary, horizontally jack the substructure
units to correctly set the centerline of bearing. Adequately account for temperature.

Unless specified elsewhere in the Contract documents, the Contractor shall locate the theoretical
centerline of bearings to within 1.5mm transverse to longitudinal girder lines; and in the direction
parallel to the longitudinal girder line locate the theoretical centerline of bearing within 6mm of the
theoretical centerline of bearing.

After setting the bearings and installing anchor rod nuts, washers and any other associated hardware
specified in the Contract documents, the Contractor shall clean the protruding/ exposed surfaces of
the assembly of all deleterious material.

23.7.6

Tightening Anchor Rod Nuts for Erection of Steel Structure

when tightening anchor rod nuts during the erection of a steel structure, the Contractor shall comply
with the specifications outlined in this section.

23.7.6.1

Tightening Fixed Bearings

The Contract

or shall tighten anchor nuts to a ‘snug tight’ condition such that the different mating

surfaces (such as the top of concrete, neoprene and steel) are in firm contact. The nut is to be tight
enough to develop friction between surfaces to prevent sliding, but not over tightened that bulging
or damage occurs in any of the mating materials.

23.7.6.2

Tightening Expansion Bearings

The Contractor shall draw down the nut such that a total gap of 1.5 mm exists between the washer
and nut and washer and bearing surface. Tighten a second nut of the same specification to a snug
tight condition against the first nut maintaining the required gap.

23.7.7

Bearings for Erection of Steel Structures

Bridge bearings shall be furnished and installed in conformance with Chapter 25, Bearing Devices.

If the steel superstructure is to be placed on a substructure that was built under a separate Contract,
the Contractor shall verify that the masonry has been constructed in the right location and to the
correct lines and elevations before ordering materials.

23.7.8

Procedure to Erect a Steel Structure

When erecting the steel structure for the Project, the Contractor shall comply with the requirements
and specifications outlined in this section.

23.7.8.1

Conformance to Project Drawings during Erection

The erection procedure shall conform to the erection drawings submitted in accordance with Section
23.3.2. Any modifications to or deviations from this erection procedure shall require revised drawings
and verification of stresses and geometry.

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-62

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

23.7.8.2

Accounting for stresses during erection of Steel Structure

Any erection stresses induced in the structure as a result of using a method of erection which differs
from the Contract documents shall be accounted for by the Contractor. Erection design calculations
for  such  changed  methods  shall  be  prepared  at  the  Contractor's  expense  and  submitted  to  the
Engineer.  The  calculations  shall  indicate  any  change  in  stresses  or  change  in  behavior  for  the
temporary  and  final  structures.  Additional  material  required  to  keep  both  the  temporary  and  final
stresses within the allowable limits used in design shall be provided at the Contractor's expense.

The Contractor shall be responsible for providing temporary bracing or stiffening devices to
accommodate handling stresses in individual members or segments of the structure during erection.
When the partial structure is deemed prone to suitability concerns, the Contractor shall provide the
requisite calculations showing that the partial structure will remain stable until the complete continuity
of the structure is reached.

23.7.8.3

Maintaining an Erected Steel Structures Alignment and

Camber

During erection, the Contractor shall be responsible for supporting segments of the structure in a
manner that will produce the proper alignment and camber in the completed structure. Cross frames
and diagonal bracing shall be installed as necessary during the erection process to provide stability
and assure correct geometry. Temporary bracing, if necessary at any stage of erection, shall be
provided by the Contractor.

23.7.8.4

Final Position of Girder Webs for a Steel Structure

Unless shown elsewhere in the Contract documents, the Contractor shall detail the girders and cross
frames as directed by the Engineer. The final condition is to be defined as with the deck and parapets
cast, but without any future wearing surface. A web will be considered plumb if it is within a tolerance
horizontally between the top and bottom of the web of 7.8mm per metre of web depth compared
against the theoretical position as required in the Contract documents. Measure the out-of-plumb
perpendicular to the face of the web. Erect trapezoidal girders to the geometry shown in the Contract
documents to the same 7.8mm per metre of web depth tolerance.

23.7.9

Field Assembly for Erection of a Steel Structure

Parts shall be accurately assembled as specified in the  Contract documents or erection drawings
and any match-marks shall be followed. Material shall be carefully handled so that no parts will be
bent, broken, or otherwise damaged. Hammering which will injure or distort the members shall not
be  done.  Bearing  surfaces  and  surfaces  to  be  in  permanent  contact  shall  be  cleaned  before  the
members are assembled. Splices and field connections shall have one-half of the holes filled with
bolts  and  cylindrical  erection  pins  (half  bolts  and  half  pins)  before  installing  and  tightening  the
balance  of  high-strength  bolts.  Splices  and  connections carrying traffic  during  erection  shall  have
three-fourths of the holes so filled.

Fitting-up bolts may be the same high-strength bolts used in the installation. If other fitting-up bolts
are used, they shall be of the same nominal diameter as the high strength bolts and cylindrical
erection pins shall be 0.8 mm larger.

23.7.10

Connection of Pins for an Erected Steel Structure

Pilot and driving nuts shall be used in driving pins. They shall be furnished by the Contractor without
charge. Pins shall be so driven that the members will take full bearing on them. Pin nuts shall be
screwed up tight and the threads burred at the face of the nut with a pointed tool.

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-63

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

23.7.11

Correcting Misfits in an Erected Steel Structure

Correction of minor misfits involving minor amounts of reaming, cutting, grinding, and chipping shall
be considered a legitimate part of the erection. However, any error in the shop fabrication or
deformation resulting from handling and transporting shall be cause for rejection.

The Contractor shall be responsible for all misfits, errors, and damage and shall make the necessary
corrections and replacements.

23.8

Expansion Joints for Steel Structures

Expansion joints shall be fabricated and installed in accordance with the requirements of this section
and the requirements of Chapter 26, Bridge Deck Joint Systems.

Complete working drawings for fabrication and installation of expansion joints shall be submitted.
The Contractor shall include the joint Manufacturer

‘s instructions for proper installation of the joint

on the drawings. Joint opening dimension for an ambient temperature of thirty degree Celsius (30°C)
and adjustments to that dimension due to temperature variations shall be shown.

The Contractor shall fabricate expansion joints accurately to conform to the specified concrete floor
section, matching cross slopes and break points. Expansion joints shall be assembled and checked
for fit in the shop, then it shall be match marked for shipment.

For sealed expansion joints, the steel receptors shall be fabricated to be continuous the full length
of joint including 150 mm extensions. The number of splices in the steel receptor shall be minimized.
To splice, a partial penetration weld, ground smooth shall be used. Welding shall not be done in
areas in contact with the neoprene.

The Contractor shall provide and install a neoprene gland continuous the full length of joint including
150 mm extensions. At locations where joints are shown to be for skew of thirty-five degree (35°)
and greater, the neoprene shall be spliced by vulcanizing or other approved method that provides
strength and durability equal to unspliced neoprene. Splices shall be permanently watertight.

23.9

Inspection and Final Acceptance for Steel Structures

The Contractor shall perform Quality Control inspections of all phases of the work. The inspection
frequency and depth shall be sufficient to ensure that all materials and workmanship incorporated
into the work meet the requirements of the Contract documents and that the processes are controlled
to ensure that the final finished product(s) conform to the physical characteristics and dimensions
required  by  the  Contract  documents.  A  Quality  Control  Manager  shall  be  responsible  for  all
inspection operations. An adequate number of Quality Control Inspectors shall be available to ensure
review  of  all  materials  and  fabrication  processes  are  preformed  in  accordance  with  the  Quality
Control Plan. Weekly meetings shall be held with the  Engineer to review inspection findings. The
review of this information is to identify any refinements and/or improvements in the process being
utilized in the work. The Engineer may alter the frequency of meetings.

Material (except bearing devices and painting) for steel structures will be evaluated under this
section. Production certifications shall be furnished for each shipment of structural steel, steel
forgings, and high-strength bolts, nuts, and washers.

Construction of steel structures shall be evaluated under this section. Bearing devices shall be
evaluated under Chapter 25, Bearing Devices. Painting shall be evaluated under Chapter 24,
Painting.

The Contractor shall ensure the final alignment, profile and fastening of the erected steel is in
accordance with the Contract documents.

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-64

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

23.10

Additional Provisions for Curved Steel Girders

Provisions of this section apply to horizontally curved girders and shall be considered in addition to
other provisions of these Specifications. However, when there is a conflict between these provisions
for curved girders and other provisions of these Specifications, these provisions shall prevail.

These provisions shall be used by the Contractor to create a construction plan as required herein.

These provisions shall apply to the superstructure including fabrication, shipping, erection of the
girders, cross-frames and other structural steel elements, and placement of the concrete deck.

23.10.1

Contract

or’s Construction Plan for Curved Girder Bridge

The Engineer

’s construction plan, if shown in the Contract documents, shall not be taken as

supplanting or implying any supplantation of the Contract

or’s responsibility for the fabrication,

erection, or construction of any part of the bridge.

The Contractor shall provide a construction plan which details fabrication, procedures for erection,
and deck placement, and which shall be referred to herein as the Contract

or’s construction plan.

This plan may be based on the plan shown in the Contract documents, if one is provided, or may be
developed entirely by the Contractor. In either event, it shall demonstrate the general stability of the
structure and individual components during each stage of construction, including while supported on
any temporary jacks. The Contract

or’s construction plan shall be stamped by a Professional

Engineer and be accepted by the Owner or the Engineer. Where the Contract

or’s construction plan

causes a difference in camber of the girders for dead load from that presented on the Contract
documents, acceptance by the Owner or the Engineer shall be obtained before commencement of
fabrication. The Contract

or’s construction plan shall include:

a.  Fabrication procedures, including method of curving the girders
b.  Shipping weights, lengths, widths, and heights, and means of shipping
c.  Erection plan, including sequence of erection; crane capacities;  and the location, capacity

and elevation of any temporary supports

d. Deck placement sequence, including the time between placements; and the magnitude and

position of any temporary load required to prevent girder lift-off at bearings

Computations which show that the factored construction stresses satisfy the requirements of Articles
6.10.3 or 6.11.3, “Constructability,” of the

AASHTO LRFD Bridge Design Specifications

, as

applicable, shall be provided.

23.10.2

Fabricating Materials for Curved Girder Bridges

The Fabricator shall ensure that the steel can be fit up in the no-load condition unless specified
otherwise in the construction plan.

23.10.2.1 Handling Materials for Curved Girder Bridges

Rolled shapes and plates composing the flanges and webs shall be handled in such a manner as to
prevent visible deformations or other incidental damage.

23.10.2.2 Fabricating Curved Girders

Fabrication of curved girders for the Owner bridges shall comply with the requirements and
specifications outlined in this section.

Fabricating Rolled I-beams

Horizontal curvature may be obtained by heat-curving. Heat-curving of beams shall be performed in
accordance with

the provisions of Article 6.7.7, “Heat-Curved Rolled Beams and Welded Plate

Girders,” of the AASHTO LRFD Bridge Design Specifications and Section 23.5.4 of these

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-65

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

Specifications. The Engineer shall determine the necessity of providing the additional camber
specified in Article 6.7.7, “Camber,” of the AASHTO LRFD Bridge Design Specifications.

Fabricating Welded I-girders

In addition to heat-curving as specified in this section, welded girders may be fabricated from cut-
curved flanges.

Vertical camber shall be obtained by cutting the web plate to the necessary contour.

Fabricating Welded Box and Tub Girders

Box flanges shall be cut-curved. Top flanges of tub girders may be curved according to the provisions
of this section.

23.10.2.3 Fabricating Web Attachments for Curved Girder Bridges

Fabrication of web attachments for curved girder bridges shall comply with the requirements and
specifications outlined in this section.

Fabricating Transverse Stiffeners

Transverse stiffeners shall be bolted to the web or welded to the web with continuous fillet welds on
both sides of the stiffener. These welds shall be terminated between 4tw and the lesser of 6tw and
100mm from the near edge of the adjacent flange or longitudinal web stiffener welds. If transverse
stiffeners or transverse web elements serving as stiffeners are interrupted by a longitudinal stiffener,
the transverse stiffeners shall be attached to the longitudinal stiffener to develop the flexural and
axial resistance of the transverse stiffener. If single-sided transverse stiffeners are used, the end of
the stiffener should be attached to both flanges. Fillet welds on both sides of the stiffener may be
used.

When pairs of transverse stiffeners are used, they shall be fitted tightly to both flanges.

Fabricating Connection Plates

Connection plates, otherwise identified as transverse stiffeners at cross-frames and diaphragms,
shall be attached to both flanges by either welding or bolting. If a bolted connection is shown on the
Contract documents, a welded connection may not be substituted without permission from the
Engineer.

Fabricating Longitudinal Stiffeners

Wherever practical, longitudinal stiffeners shall extend uninterrupted over their specified length
unless otherwise permitted in the Contract documents. Longitudinal stiffeners shall be bolted to the
web or welded to the web with continuous fillet welds on both sides of the stiffener.

Where longitudinal stiffeners are interrupted, they should be fitted to, and attached to, the continuous
element sufficiently to develop the required strength and stiffness of the longitudinal stiffener.

Fabricating Cross-frames and Diaphragms

Cross-frames and diaphragms shall be detailed to fit under the no-load condition unless otherwise
specified.

23.10.2.4 Fabricating Bolt Holes for Curved Girder Bridges

Unless permitted otherwise in the Contract documents, bolt holes in girder splices and primary load-
carrying members shall be standard size. Exceptions shall be approved by the Engineer.

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-66

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

23.10.2.5 Tolerances in Curved Girder Bridges

Materials for curved girder bridges shall comply with the requirements and specifications outlined in
this section.

Tolerance for Welded Web Flatness in Curved Girder Bridges

Webs shall meet dimensional tolerances specified in the AASHTO/AWS D1.5M/D1.5:2010,

Bridge

Welding Code

. Flatness shall be measured with respect to a straightedge oriented perpendicular to

the flanges.

Tolerance for Camber in Curved Girder Bridges

Cambers provided on the Contract documents shall be adhered to unless steel erection or deck
placement is to be performed in a manner that will lead to deflections different from those used to
determine the camber specified. If the Contractor or the Contract

or’s Fabricator/Detailer or Erector

intends other procedures or outcomes, the approach shall be confirmed with the Engineer, and any
documentation required for approval shall be provided at no cost to the Owner. Any required
submissions should be made and approved before the submission of the shop drawings for approval.

Tolerance for Sweep in Curved Girder Bridges

Sweep tolerance shall meet the requirements of the AASHTO/AWS D1.5M/D1.5:2010,

Bridge

Welding Code

. Sweep tolerance shall be measured radially from the theoretical curve of the girder.

Tolerance for Lengths of Curved Girders

Girder lengths shall be determined based on an ambient temperature of 30

C. Girder length shall

be measured along the arc.

23.10.2.6 Fabricating Fit-up for Curved Girder Bridges

Fit-up of girder sections shall meet the provisions of Section 23.6.6

, “Preassembly of Field

Connections for Steel Structures

,” of these Specifications. Unless otherwise specified in the

Contract

or’s construction plan, fit-up shall be assumed to be performed under the no-load condition.

When numerically controlled drilling is employed, trial fit-up of cross-frames or diaphragms between
properly positioned girder sections shall be performed as specified in Article 23.6.1.4 of these
specifications.

Shop fit-up of bolted connections in load-carrying connections of cross-frames and diaphragms to
the girders may be required for structures with complex geometry or stiff elements.

Girder Section Field Splices may be fit up in either the vertical or horizontal position. Girder splices
may be fit up before heat-curving.

23.10.3

Transportation Plan for Curved Girders

A Transportation Plan may be required by the Owner or the Engineer for complex or large structures.
The type of girder supports required and their locations shall be identified. The types, size, and
locations of tie-downs shall be shown. A sufficient number of tie-downs shall be specified to provide
adequate redundancy.

Girder stresses due to selfweight while being shipped shall be computed with a dynamic load
allowance of 100 percent.

The computed girder stresses shall satisfy the provisions of Article 6.10.3.2 or Article 6.11.3.2 of the

AASHTO LRFD Bridge Design Specifications

, as applicable.

Fatigue stresses shall not exceed the constant amplitude fatigue threshold for the appropriate
categories in Table 6.6.1.2.5-3 of the AASHTO LRFD Bridge Design Specifications.

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-67

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

Wherever practical, girder sections should be shipped in the same orientation as in the completed
structure. Girders shall be supported in such a manner that their cross-section shape is maintained
and through-thickness stresses are minimized.

Supports should be such to ensure that dynamic lateral bending stresses are controlled.

Temporary stiffening trusses or beams, if required to meet the requirements of this section, shall be
specified in the Transportation Plan.

23.10.4

Erecting Steel for Curved Girder Bridges

Erection shall be performed in accordance with the Contract

or’s construction plan as approved by

the Engineer.

Factored stresses due to selfweight of the steel and wind at each stage of erection shall not exceed
those computed according to the provisions of Article 6.10.3 or Article 6.11.3, as applicable, of the
AASHTO LRFD Bridge Design Specifications and Article 23.7.8.2

, “Accounting for stresses during

erection of steel structures

”, of these Specifications.

Reaming of bolt holes during erection shall be permitted only with the approval of the Engineer.

Bolted girder splices shall be field assembled according to the provisions of Section 23.6.1 of these
Specifications.

23.10.4.1 Erecting Falsework for Curved Girder Bridges

Falsework shall be designed to carry vertical and lateral loads that are specified in the construction
plan. The elevation of falsework shall be such as to support the girders at the cambered no-load
elevation. Jacks used in conjunction with the falsework shall have a stroke adequate to permit full
unloading. Unloading of temporary supports should be performed such that all temporary supports
at each cross-section are unloaded uniformly.

Where appropriate, cranes may be substituted for falsework.

23.10.4.2 Erecting Bearings for Curved Girder Bridges

Computed bearing rotation during construction shall not exceed the rotational capacity of the
bearing. Bearings shall be installed such that, after dead load has been applied, sufficient rotation
capacity shall be available to accommodate rotations due to environmental loads and live load.
Expansion bearings shall be installed so that they will be in the center of the permitted travel at the
ambient temperature of 30° C unless otherwise specified by the Engineer.

23.10.4.3 Erecting I-girders for Curved Girder Bridges

The Contractor shall ensure that girders are stable throughout the erection process. The stage of
completeness of the bolted connections shall be considered when evaluating the strength and
stability of the steel during erection.

23.10.4.4 Erecting Closed Box and Tub Girders for Curved Girder

Bridges

The Contractor shall ensure that the cross-section shape of each box is maintained during erection.

Top lateral bracing should be installed in tub girders before shipping and erection of the field pieces.

23.10.5

Erecting Decks for Curved Girder Bridges

When erecting decks for the curved girder bridge for the Project, the Contractor shall comply with
the requirements and specifications outlined in this section.

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-68

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

23.10.5.1 Erecting Forms for Decks on Curved Girder Bridges

Plywood, permanent metal forms, or concrete panels may be used as deck forms as approved by
the Engineer. Proprietary forms shall be placed in accordance with the Manufacturer

’s specifications

incorporating any modifications to those Specifications approved by the Engineer. Form work shall
be supported by the superstructure.

Erecting Overhangs for Decks on Curved Girder Bridges

Overhang forms shall be removed after the deck has cured. Wherever practical, overhang brackets
should bear near the bottom flange and be attached to the top flange. If overhang brackets bear
against the web, the Contractor shall ensure that precautions have been taken to prevent permanent
deformation of the web and excessive deflection of the wet slab and forms. The lateral force on the
top flange due to overhang brackets shall be investigated to ensure that the flange is adequate as
specified in Article 6.10.3.4, “Deck Placement,” of the AASHTO LRFD Bridge Design Specifications.

Loads applied on the overhang brackets shall be considered in determining lateral flange bending
stresses, cross-frame forces, and associated web and top flange deformations. If the loads or their
application are to be different than those provided for in the Contract documents, an additional
analysis shall be made by the Contractor and approved by the Engineer.

Erecting Tub Girders for Decks on Curved Girder Bridges

Deck forms shall not be supported at locations other than girder flanges unless specifically
considered in the design.

23.10.5.2 Placing Concrete for Decks on Curved Girder Bridges

Concrete placements shall be made in the sequence specified in the approved construction plan.
Time between placements shall be such that the concrete in prior pours has reached an age or
strength specified in the construction plan. Any accelerating or retarding agents to be used in the
concrete mix shall be specified.

Duration of each placement shall be specified in the construction plan. Placements that include both
negative and positive dead load moment regions should be placed such that the positive moment
region is poured first.

23.10.6

Reporting Modification to Construction Plan for Curved Girder
Bridge

Any modifications to the construction plan in the field from the original plan shall be documented with
appropriate approvals noted.

23.11

Post-weld Treatment for Steel Structures

Post-weld treatments for steel structures shall comply with the requirements and specifications
outlined in this section.

Typical post-weld treatment includes ultrasonic impact treatment, heat treatment, grinding, weld toe
remelting (GTAW dressing or plasma arc dressing), hammer peening, and shot peening.

23.11.1

Ultrasonic Impact Treatment for Steel Structures

If required, the objective of ultrasonic impact treatment (UIT) is to improve the fatigue strength of
welded connections by plastically deforming the material at the weld toes and introducing residual
compressive stresses substantially greater than the largest anticipated tensile stresses to a depth of
no less than 0.5mm. This treatment is necessary only at the weld toe which is defined as the interface
of the weld metal and base metal. Due to the finite size of the UIT needles and the recommended
treatment procedure, some base metal adjacent to the weld toe will get treated.

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-69

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

23.11.1.1 Procedure for Ultrasonic Impact Treatment for Steel

Structures

UIT shall be accomplished in accordance with the equipment Manufacturer

’s recommendations,

except as specifically described in the Contract documents.

The use of UIT shall be limited to base metal with a specified minimum yield strength of 690 MPa or
less.

Before UIT, the weld toe to receive UIT shall be visually inspected and magnetic particle-tested for
conformance to the quality standards specified in the Contract documents. The instrument shall be
calibrated against the maximum flaw size allowed. Discontinuities greater than 0.8mm shall be
repaired satisfactorily before initiating the work.

UIT shall be done along the toe of the weld in a manner that will cause the center of the resultant
treatment groove to be at the weld toe, with equal treatment and smooth transition to the adjacent
weld and base metal.

UIT shall be performed so as to result in a uniform groove with a distinct and uniform bright metallic
surface, as verified by visual inspection immediately after completion. When viewed under a 10x
magnifying glass, the groove shall be free from any visible indications of the untreated base metal
or weld metal. If such untreated indications exist within the treated area, such area shall be retreated
to obtain a uniform, bright metallic surface across the entire surface of the UIT groove.

23.11.1.2 Other Weld Metal and Base Metal Treatments

Because the benefits of UIT are primarily derived from the introduction of compressive residual
stresses, the Contractor shall avoid other processes, such as heat treatment, hot dipped galvanising,
or overloading, that might relieve these stresses after performing the toe treatment.

23.11.1.3 Dead Load Consideration

If the structure is going to be subjected to a significant dead load when in use, it is advisable that
this be taken into consideration and the structure be loaded before treatment. An enhancement
corresponding to the lower stress ratio may be obtained in that case, depending on the live load
stress ratio of the nominal stress cycles applied after the treatment.

23.12

Additional Requirements for Steel Structures

In addition to the requirements of these specifications, the fabrication, transport and erection of steel
structures shall also conform to the following additional requirements.

Steel with Enhanced Through Thickness Properties

Where the Contract plans indicate a requirement for steel with enhanced through thickness
properties, these shall be in accordance with BS EN 10164:2004,

Steel products with improved

deformation properties perpendicular to the surface of the product - Technical delivery conditions,

an equivalent specification approved by the Engineer.

Laminar Defects in Plate Material

The areas of plates presented in

Table 23-13, shall not have laminations exceeding the limits specified in BS EN 10160:1999,

Ultrasonic testing of steel flat product of thickness equal or greater than 6 mm (reflection method)

Table 23-13 presents acceptance levels for internal imperfections in steel plate, strip and wide flats,
based on Ultrasonic Testing.

Table 23-13: Acceptance Levels for internal imperfections in steel plates

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-70

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

Acceptance
Level

For a band of flange or web plate of width 25 times the plate thickness on each
side of a bearing diaphragm where attached by welding:

For a band of web plate of width 25 times the plate thickness on each side of a
single sided bearing stiffener where attached by welding :

For edges of plates where corner welds will be made on to the surface of such
plates:

For welded cruciform joints transmitting primary tensile stresses through the plate
thickness, on a band of width four times the thickness of the plate each side of
the proposed attachment:

Dimensions of Cope Holes

The radius of cope holes and of re-entrant corners in plate material shall be the greater of 30mm or
2 times the plate thickness unless specified otherwise in the Contract plans.

Reference Temperature

Dimensions of steel structures shown on the Contract plans shall be correct at the specified mean
temperature.

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-71

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

NDEX

abutment, 23-4
allowable temperature, 23-28, 23-29
arc process, 23-58
artificial cooling, 23-29
bearing, 23-4, 23-21, 23-30, 23-31, 23-34, 23-

36, 23-38, 23-40, 23-45, 23-46, 23-47, 23-
53, 23-55, 23-62, 23-63, 23-64, 23-65, 23-
68, 23-71

Bracing members, 23-4
Bridge bearings, 23-63
bridge structures, 23-59
bulk materials, 23-14
calibrated wrench, 23-49, 23-52, 23-53, 23-54
camber, 23-15, 23-16, 23-17, 23-31, 23-37,

23-45, 23-47, 23-63, 23-65, 23-66, 23-67

Camber, 23-17, 23-31, 23-37, 23-38, 23-63,

23-66, 23-67

cold bending, 23-26
collar fasteners, 23-21, 23-22, 23-56
connection plates, 23-4, 23-30, 23-31, 23-33,

23-35

container, 23-14, 23-15, 23-51
Cross frames, 23-4, 23-14, 23-63
Cup and countersunk bolts, 23-22
curvature, 23-27, 23-29, 23-30, 23-31, 23-41,

23-42, 23-66

curved beams, 23-4, 23-39
dead load, 23-16, 23-17, 23-31, 23-38, 23-65,

23-68, 23-69, 23-70

Deck forms, 23-69
Department of Transport, 23-4
diaphragms, 23-4, 23-18, 23-43, 23-61, 23-66,

23-67

dimensional tolerances, 23-37, 23-38, 23-67
direct tension indicator (DTI) devices, 23-54
drilled holes, 23-33
Electroslag Welding, 23-58
equipment, 23-27, 23-34, 23-42, 23-43, 23-59,

23-60, 23-70

erection, 23-4, 23-14, 23-15, 23-16, 23-17, 23-

40, 23-41, 23-42, 23-43, 23-44, 23-45, 23-
46, 23-60, 23-61, 23-62, 23-63, 23-64, 23-
65, 23-67, 23-68, 23-70

Erection design calculations, 23-63
Erection Quality Control, 23-60
Expansion joints, 23-64
fabricated girders, 23-4
Fabricator, 23-12, 23-13, 23-14, 23-15, 23-17,

23-18, 23-26, 23-27, 23-28, 23-29, 23-30,
23-31, 23-32, 23-33, 23-34, 23-35, 23-36,
23-38, 23-43, 23-45, 23-65, 23-67

Falsework, 23-4, 23-15, 23-16, 23-60, 23-68

field connections, 23-34, 23-43, 23-64, 23-67
field-welded connections, 23-47
flame-cut, 23-40
fracture critical, 23-14, 23-18, 23-33, 23-35,

23-58

friction grip bolts, 23-46
full-size tests, 23-42
galvanising, 23-20, 23-21, 23-24, 23-37, 23-

51, 23-70

girders, 23-4, 23-14, 23-16, 23-17, 23-18, 23-

29, 23-30, 23-31, 23-33, 23-34, 23-37, 23-
38, 23-39, 23-40, 23-45, 23-61, 23-63, 23-
65, 23-66, 23-67, 23-68

harmful materials, 23-14
Head markings, 23-20
heat-curving bridge members, 23-29
heating patterns, 23-28, 23-30, 23-32
higher standards, 23-4
horizontal radius, 23-30
inspection frequency, 23-64
jacks, 23-28, 23-32, 23-65
large diametre holes, 23-36
lateral bracing components, 23-33, 23-34
lighting poles, 23-58
load carrying capacity, 23-16
Load-indicating devices, 23-22
Lock nuts, 23-22
lubricants, 23-37, 23-61
Magnetic particle examination, 23-32
Maximum deviation, 23-38, 23-41, 23-42
moisture, 23-14, 23-15, 23-49
non-destructive testing, 23-4, 23-32
Non-Redundant Members, 23-18
orthotropic-deck bridge, 23-41
Overhang forms, 23-69
permanent metal forms, 23-69
pier, 23-4, 23-37
pinholes, 23-38
Post-weld treatments, 23-69
preheat, 23-25
Preload compressive stresses, 23-28
primary load, 23-4, 23-14, 23-18, 23-32, 23-

35, 23-51, 23-61, 23-62, 23-67

Radiographic examination, 23-32
reaming, 23-34, 23-35, 23-36, 23-45, 23-46,

23-47, 23-48, 23-64

Rib members, 23-4
rolled beams, 23-4, 23-14, 23-18, 23-30, 23-

shear studs, 23-14
sign structures, 23-58
slip-critical connections, 23-48, 23-49

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 23-72

HAPTER

23:

TEEL

TRUCTURES

First Edition -January 2018

slotted hole geometry, 23-35
splice plates, 23-14, 23-18, 23-26
stainless steel, 23-19, 23-41
standard hole, 23-33
steel arches, 23-4
Steel castings, 23-23
Steel forgings, 23-23
Steel surfaces, 23-39
structural members, 23-14, 23-42
Stud shear connectors, 23-22
supplier, 23-14, 23-20
Surface finishes, 23-36
Tack welds, 23-60
Tensile properties, 23-22, 23-23
Threads, 23-5, 23-40, 23-47, 23-50
torches, 23-28, 23-40
traffic signal poles, 23-58
truss chords, 23-38, 23-43
truss members, 23-4, 23-43
turn-of-nut, 23-47, 23-53
Ultrasonic, 23-10, 23-11, 23-32, 23-59, 23-60,

23-69, 23-70

ultrasonic examination, 23-26, 23-58, 23-60
Visual inspection, 23-26, 23-32, 23-59
V-type heating, 23-29
Washers, 23-7, 23-15, 23-20, 23-21, 23-22,

23-51, 23-52

Welder qualification, 23-25
welder qualifications, 23-58
welding, 23-9, 23-11, 23-16, 23-18, 23-19, 23-

22, 23-24, 23-25, 23-26, 23-30, 23-31, 23-
33, 23-40, 23-41, 23-58, 23-59, 23-60, 23-
66, 23-71

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page i

HAPTER

24:

AINTING

First Edition -January 2018

Chapter 24: Painting

ABLE OF

ONTENTS

Table of Contents............................................................................................................................. i

List of Tables .................................................................................................................................. iii

Painting ........................................................................................................................... 24-1

24.1

General ........................................................................................................................ 24-1

24.1.1

Protection of Public, Property, and Workers .......................................................... 24-1

24.1.2

Existing Paint Removal ......................................................................................... 24-1

24.1.3

Protection of Work ................................................................................................ 24-2

24.1.4

Qualification Samples and Tests ........................................................................... 24-2

24.1.5

General Requirements for Surface Preparation .................................................... 24-3

24.1.6

General Requirements for Paint Application ......................................................... 24-3

24.2

Reference Standards and Codes ................................................................................. 24-4

24.3

Painting Structural Iron and Steel Surfaces .................................................................. 24-9

24.3.1

General ................................................................................................................. 24-9

24.3.1.1

Compatibility ................................................................................................ 24-10

24.3.1.2

Toxicity ........................................................................................................ 24-10

24.3.1.3

Volatile Organics.......................................................................................... 24-10

24.3.1.4

Color ............................................................................................................ 24-10

24.3.1.5

Performance Requirements ......................................................................... 24-10

24.3.2

Paint Systems for New External Visible Surfaces or Surfaces with All Existing Paint

Removed .......................................................................................................................... 24-12

24.3.2.1

Paint System No. 1 - Inorganic Zinc Silicate System .................................... 24-13

24.3.2.2

Paint System No. 2

– Zinc Rich Epoxy System ............................................ 24-14

24.3.2.3

Paint System No. 3

– Moisture Cured Polyurethane System ....................... 24-14

24.3.2.4

Paint System No. 4

– Acrylic Latex System ................................................. 24-16

24.3.2.5

Paint System No. 5

– Low VOC Alkyd System ............................................. 24-16

24.3.3

Paint Systems for Surfaces with Existing Sound Paint ........................................ 24-17

24.3.3.1

Paint System No. 6

– Moisture Cured Polyurethane System ....................... 24-18

24.3.3.2

Paint System No. 7

– Low VOC Alkyd System ............................................. 24-18

24.3.3.3

Paint System No. 8

– Low Viscosity Epoxy System ..................................... 24-18

24.3.4

Paint System No. 9 for New Internal Invisible Surfaces....................................... 24-18

24.3.5

Surface Preparation of Iron and Steel Surfaces .................................................. 24-18

24.3.5.1

New surfaces or Surfaces with all Existing Paint Removed .......................... 24-18

24.3.5.2

Surfaces with Existing Sound Paint.............................................................. 24-19

24.3.5.3

Cleaning Methods of Iron and Steel Surfaces .............................................. 24-19

24.3.6

Sampling and Testing ......................................................................................... 24-22

24.3.7

Time of Application ............................................................................................. 24-22

24.3.8

Storage of Paint and Thinner .............................................................................. 24-23

24.3.9

Mixing and Thinning ............................................................................................ 24-23

24.3.10

Application of Paint ............................................................................................. 24-24

24.3.10.1

General ........................................................................................................ 24-24

24.3.10.2

Brush Application ......................................................................................... 24-25

24.3.10.3

Spray Application of Paint ............................................................................ 24-25

24.3.10.4

Shop Painting .............................................................................................. 24-26

24.3.10.5

Field Painting ............................................................................................... 24-26

24.3.10.6

Drying of Painted Iron and Steel .................................................................. 24-27

24.3.10.7

Handling of Painted Iron and Steel .............................................................. 24-27

24.3.10.8

Measurement of Dry Film Thickness (DFT) of Paints ................................... 24-27

24.4

Painting Galvanized Surfaces .................................................................................... 24-29

24.4.1

Paint System No. 10

– Polyamide Cured Rust Inhibitive Epoxy System ............. 24-30

24.4.2

Paint System No. 11

– Vinyl Wash System ......................................................... 24-30

24.5

Painting Steel Sheet, H, Pipe Pilings, and other Surfaces .......................................... 24-31

24.5.1

Surface Preparation ............................................................................................ 24-31

24.5.2

Application Requirements ................................................................................... 24-31

TANDARD

ONSTRUCTION SPECIFICATIONS

PART

–

OAD

TRUCTURES

Page 24-1

HAPTER

24:

AINTING

First Edition -January 2018

PAINTING

24.1

General

This specification sets out the minimum requirements and the standards for surface treatment and
painting of structural iron and steel, galvanized, aluminium, and concrete surfaces to control
corrosion and deterioration.

The Contractor shall comply with the specifications in this chapter and the Contract documents when
performing painting services for the Project. Painting services shall include at least the following
activities:

•

Preparing surfaces

•

Applying paint (painting surfaces)

•

Curing paint

•

Protecting works under construction, existing facilities, vehicles, and the public from damage

caused by painting

•

Furnishing of all labour, equipment, and materials needed to perform painting services

•

The applicator/painter shall demonstrate to the Engineer his proficiency in applying the

manufacturer’s recommendations

24.1.1

Protection of Public, Property, and Workers

The  Contractor  shall comply  with  the  Steel  Structures  Painting  Council's  (SSPC) Guide  to  Safety
and  Health  Requirements  (SSPC-PA  Guide  10),  and  OSHA  requirements.  All  applicable
environmental  protection  and  occupational  safety  and  health  standards,  rules,  regulations,  and
orders  shall  be  observed  by  the  Contractor.  Failure  to  comply  with  these  standards,  rules,
regulations, and orders shall be sufficient cause for suspension or disqualification.

All reasonable precautions shall be taken to contain waste materials, including used blasting material
and old paint, classified as hazardous. Disposal of hazardous waste material shall be performed in
accordance with all applicable laws.

Protective devices, such as tarps, screens, or covers, shall be provided by the Contractor, as
necessary, to prevent damage to the work and to other properties, or persons from all cleaning and
painting operations. All damage caused by the painting works to vehicles, persons, or property shall
be the responsibility of the Contractor.

Paint or paint stains that result in an unsightly appearance on surfaces not designated to be painted
shall be removed or obliterated by the Contractor at its expense.

24.1.2

Existing Paint Removal

If the paint being removed is a hazardous material containing lead or chromium, the Contractor shall
comply with all the following:

•

SSPC Guide 6I(CON) - Guide for Containing Debris Generated During Paint Removal

Operations;

•

SSPC Guide 7I(DIS) - Guide for the Disposal of Lead-Contaminated Surface Preparation

Debris;

•

40 CFR Parts 260 - 268 - Code of Federal Regulations;

•

29 CFR 1926.62 - OSHA Construction Industry Standards for Lead;

•

40 CFR 50.6 - EPA National Primary and Secondary Ambient Air Quality Standards for

Particulate Matter; and

•

40 CFR 50.12 - EPA National Primary and Secondary Ambient Air Quality Standards for

Lead.

Abu Dhabi, United Arab Emirates. STANDARD CONSTRUCTION SPECIFICATIONS (PART 2 - ROAD STRUCTURES, 2020) - page 11