BWC-6-I1

© 2011 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.

ISBN: 978-1-56051-515-9 Publication Code: BWC-6-I1

American Association of State Highway and Transportation Officials 444 North Capitol Street, NW Suite 249

Washington, DC 20001 202-624-5800 phone/202-624-5806 fax

www.transportation.org

© 2011 by the American Association of State Highway and Transportation Officials. All rights reserved. Duplication is a violation of applicable law. Cover photo provided by L.B. Foster-Precise Structural Steel Division, Georgetown, MA.


INSTRUCTIONS AND INFORMATION

General AASHTO has issued proposed interim revisions to the Bridge Welding Code (2011). This packet contains the revised

pages. They are not designed to replace the corresponding pages in the book but rather to be kept with the book for fast reference.

A Note on the Use of These Interims

These interims are being provided to owners and fabricators for informational purposes only and are intended to alert them to proposed revisions to the AASHTO/AWS D1.5M/D1.5:2010 Bridge Welding Code. These interims have re-ceived initial approval from the AWS D1 Committee and the AASHTO Subcommittee on Bridges and Structures. How-ever, they will not officially revise the Bridge Welding Code until they have gone through the complete AWS consensus review and approval process and are incorporated into the next published edition of the AASHTO/AWS D1.5M/D1.5 Bridge Welding Code. This review and approval process can result in additional revisions to these interims before their final adoption. Owners have the option of implementing these interims in current projects by specifying their use in the project specifications.

Affected Articles

Underlined text indicates revisions that were approved in 2011 by the AASHTO Highways Subcommittee on Bridges and Structures. Strikethrough text indicates any deletions that were likewise approved by the Subcommittee. A list of affected articles is included below.

All interim pages have a page header displaying the section number affected and the interim publication year. Please note that these pages may also contain nontechnical (e.g. editorial) changes made by AASHTO publications staff; any changes of this type will not be marked in any way so as not to distract the reader from the technical changes.

Table i—2011 Changed Articles

SECTION 3: WORKMANSHIP

3.5.1.7 C-3.5.1.7

SECTION 4: TECHNIQUE 4.5.2.1 4.5.2.2 4.5.2.3 C-4.5.2.3 SECTION 5C: QUALIFICATION PART B SECTION 6: INSPECTION 6.7.6.2 SECTION 12: AASHTO/AWS FRACTURE CONTROL PLAN (FCP) FOR NONREDUNDANT MEMBERS


SECTION 3 AASHTO 2011 INTERIM TO THE BRIDGE WELDING CODE, 6TH EDITION

SECTION 3: WORKMANSHIP

In Article 3.5.1.7, revise the following paragraph and add a new paragraph and new Figure 3.4 as follows: 3.5.1.7 Combined warpage and tilt of flange at any cross section of welded I or H shaped beams or girders girders or beams shall be determined by measuring the offset at the toe of the flange from a line normal to the plane of the web through the intersection of the centerline of the web with the outside surface of the flange plate. This offset shall not exceed 1/100 of the total width of the flange or 6 mm [1/4 in.], whichever is greater, at any point along the member, except that at any bearing this offset should not exceed that described in 3.5.1.9 and that abutting parts to be joined by groove welds in butt joints shall conform to 3.3.3. For top flanges of open-section box girders, combined warpage and tilt of flange shall be determined by measuring the offset at the toe of the flange from a line through the intersection of the centerline of the web with the outside surface of the flange plate, at the designed angle of the flange to the web. The offset shall not exceed 1/50 of the distance from the web centerline to the nearest edge of the flange or 6 mm [1/4 in.], whichever is greater (see Figure 3.4).

Figure 3.4–Flange Offset for Box Girders

In Article C-3.5.1.7, revise the following paragraphs and add a new paragraph as follows: C-3.5.1.7 This is a historic workmanship provision that has produced good results for I or H beams and girders. For a completed web-to-flange intersection to be square, components must be properly oriented before welding. To produce a member that has the web square, the web should be normal to the flange before welding. Fixturing the flanges against rotation during welding and sequencing the welding to avoid rotation are also helpful in providing a square joint. Multipass welds should be deposited in a manner that will balance shrinkage stresses on each side of the web-to-flange weld. Generous tilt tolerances are provided for locations between bearing points, except that parts to be joined by welding or bolting need to align in assembly. The flanges need to be approximately square with the web, or at least have the same tilt as the adjacent pieces, where splices are to be made. Similar to I and H shapes, tilt and warpage (flatness) tolerances apply to the flanges of box or tub girders, regardless of the orientation of the web(s). At bearing points, the flanges should be normal and square with the web vertical centerline of the member. Bearing stiffeners simplify fabrication of flat bearing surfaces, particularly when combined with a mill-to-bear and fillet welded bearing stiffener-to flange joint (see 3.5.1.9).




SECTION 4: TECHNIQUE

In Article 4.5.2.1, revise the following paragraph:

4.5.2.1 Electrodes exposed to the atmosphere upon removal from drying or storage holding ovens or hermetically sealed containers shall be used within the time limit shown in Table 4.7 or redried at 230°C [450°F] to 290°C [550°F] for two hours minimum, except as provided in 4.5.2.3. In Article 4.5.2.2, revise the following paragraph: 4.5.2.2 Electrodes exposed to the atmosphere for periods less than those allowed by Table 4.7 may be returned to a holding oven maintained at 120°C [250°F] minimum and after a minimum period of four hours at that temperature may be reissued. The provisions of 4.5.4 shall apply. In Article 4.5.2.3, revise the following paragraph: 4.5.2.3 Optional Supplemental Moisture-Resistant Designators. E70XX-X, E80XX-X, E90XX-X, E100XX-X and E110XX-X Eelectrodes with the AWS filler metal specifications optional supplemental moisture resistance designator “R” may be exposed to the atmosphere for up to nine hours when welding steels with a minimum specified yield strength of 345 MPa [50 ksi] or less. Moisture-resistant electrodes shall be received in containers that bear the additional designator “R” as part of the AWS classification. Add the following to Table 4.7:

Table 4.7 Allowable Atmospheric Exposure of Low-Hydrogen SMAW Electrodes

Electrode Hoursa A5.1

E70XX

4 max. A5.5

E70XX-X E80XX-X E90XX-X E100XX-X E110XX-X

4 max. 2 max. 1 max.

1/2 max. 1/2 max.

a See 4.5.2.3. In Article C-4.5.2.3, revise the following paragraph: C-4.5.2.3 Optional Supplement Moisture-Resistant Designators. In order for a low-hydrogen electrode to be designated as low-moisture-absorbing with the “R” suffix designator, electrodes are tested by exposure to 27°C [80°F] and 80% relative humidity for a period of not less than 9 hours. These tests are defined in AWS A5.1/A5.1M and A5.5/A5.5M, and are typically conducted by the electrode manufacturer. The nine hour time period was selected based upon a typical work shift length, including meal time. The moisture content of the exposed covering must not exceed the maximum specified moisture content for the “R” designated electrode and classification in the appropriate A5.1/A5.1M or A5.5/A5.5M specification. Such R-designated E70XX-X, E80XX-X, E90XX-X, E100XX-X and E110XX-X electrodes may be used with exposure times of up to nine hours on steels with a minimum specified yield strength of 345 MPa [50 ksi]. For higher strength steels other electrodes, exposure time is limited to that described in Table 4.7.



SECTION 5 AASHTO 2011 INTERIM TO THE BRIDGE WLEDING CODE, 6TH EDITION

SECTION 5: QUALIFICATION

Part B—Welder, Welding Operator, and Tack Welder Qualification Add the following to the end of the 2nd paragraph:

Vision acuity is important and necessary for welders, welding operators, and tack welders to perform their jobs in an acceptable manner. Testing is not a guarantee that their vision will continue to remain acceptable. If it appears that an individual is having difficulty seeing properly, a vision acuity test should be performed.




SECTION 6: INSPECTION

In Article 6.7.6.2, revise the following paragraph: 6.7.6.2 The yoke method shall be performed in conformance with ASTM E 709, and the standard of acceptance shall be in conformance with 6.26. (1) Testing by the yoke method shall be performed using half-wave rectified DC or AC DC, DC Pulsed, or AC. (2) Electromagnetic yokes shall have lifting forces conforming to the following requirements:

Yoke Pole Leg Spacing (YPS), mm [in]

Current Type 50 ≤ YPS < 100 [2 ≤ YPS < 4]

100 ≤ YPS < 150 [4 ≤ YPS ≤ 6]

AC

Not Applicable 45 N [10 lb] 45 N [10 lb]

DC Half-Wave Rectified DC or DC Pulsed

135 N [30 lb]

225 N [50 lb]




SECTION 12: AASHTO/AWS FRACTURE CONTROL PLAN (FCP) FOR NONREDUNDANT MEMBERS

Delete existing Tables 12.3 and 12.4 and replace with the following proposed Tables 12.3, 12.4, 12.5 and 12.6. The two new additional tables result from separating SI and Metric units. Existing Table 12.5 will be re-numbered 12.7 and all references to the tables in other sections will be revised editorially.

Heat Input (as calculated by 5.12) kJ/mm

1.2 < HI 2.0 2.0 < HI 2.8 HI > 2.8

Thickness t, mm H4 H8 H16 H4 H8 H16 H4 H8 H16

t 40 50 70 40 40 50 40 40 40

20 < t 40 70 80 100 50 70 80 40 50 70

40 < t 60 90 110 120 80 90 110 70 80 90

t > 60 150 160 180 140 150 160 120 140 150

Heat Input (as calculated by 5.12) kJ/in

30 < HI 50 50 < HI 70 HI > 70

Thickness t, in H4 H8 H16 H4 H8 H16 H4 H8 H16

t 3/4 100 125 150 100 100 125 100 100 100

3/4 < t 1-1/2 150 175 200 125 150 175 100 125 150

1-1/2 < t 2-1/2 200 225 250 175 200 225 150 175 200

t > 2-1/2 300 325 350 275 300 325 250 275 300

Heat Input (as calculated by 5.12) kJ/mm

1.2 < HI 2.0 2.0 < HI 2.8 HI > 2.8

Thickness t, mm H4 H8 H16 H4 H8 H16 H4 H8 H16

t 40 50 70 40 40 50 40 40 40

20 < t 40 90 110 120 80 90 110 70 80 90

40 < t 60 150 160 180 140 150 160 120 140 150

t > 60 180 190 200 160 180 190 150 160 180


SECTION 12 AASHTO 2011 INTERIM TO THE BRIDGE WLEDING CODE, 6TH EDITION

Heat Input (as calculated by 5.12) kJ/in

30 < HI 50 50 < HI 70 HI > 70

Thickness t, in H4 H8 H16 H4 H8 H16 H4 H8 H16

t 3/4 100 125 150 100 100 125 100 100 100

3/4 < t 1-1/2 200 225 250 175 200 225 150 175 200

1-1/2 < t 2-1/2 300 325 350 275 300 325 250 275 300

t > 2-1/2 350 375 400 325 350 375 300 325 350


Date post:	19-Jan-2016
Category:	Documents
Upload:	waldo-at
View:	7 times
Download:	4 times

BWC-6-I1

Documents