Section 4152.  Structural Steel

                                                     

4152.01      general requirements.

Meet the following requirements unless alloy steel is specified in the contract documents. For alloy steel, meet the requirements specified in the contract documents for each project on which such steel is specified.

 

4152.02      STRUCTURAL STEEL.

 

A.    Use the type and quality designated in the contract documents. When not specifically designated, use structural carbon steel meeting the requirements of ASTM A 709 Grade 36. Miscellaneous items not commonly rolled from steel meeting these requirements may be furnished in other grades of steel with the Engineer’s approval.

 

B.    Unless noted otherwise, apply Charpy V-notch toughness requirements of Table 4152.02-1 to the following members. Ensure members are sampled and tested according to AASHTO T 243 (ASTM A 673).

 

1.     Flange and web plates of welded plate girders.

 

2.     Rolled section main beams, stringers, and welded cover plates.

 

3.     Flange and web splice plates.

 

4.     Rolled or welded floor beams, abutment diaphragms, and cross frames carrying direct live loads, and all parts, except shear connectors, welded to each of these members.

 

5.     Lateral bracings and connecting gusset plates in horizontally curved bridges.

 

C.    The contract documents may also designate other members to which toughness requirements apply.

 

Table 4152.02-1: Non-Fracture Critical Impact Test Requirements

Grade

Thickness (in.)

Minimum Average Energy,
ft.lbf. at °F

36T(a)

to 4

15 at 40

50T(a, b), 50WT(a, b)

 

HPS 50WT(a, b)

to 2

over 2 to 4

to 4

15 at 40

20 at 40

20 at 10

HPS 70WT (c)(d), HPS 100WT(c)

to 4

to 2 1/2

over 2 1/2 to 4

25 at -10

25 at -30

35 at -30

(a)    CVN-impact testing of "H" heat frequency testing according to ASTM A 673.

(b)    If the yield point of the material exceeds 65 ksi, reduce the testing temperature for the minimum average energy required by 15°F for each increment of 10 ksi above 65 ksi. The yield point is the value given on the certified "Mill Test Report".

(c)    CVN-impact testing of "P" plate frequency testing according to ASTM A 673.

(d)    If yield strength of structural product exceeds 85 ksi, testing temperature for minimum average energy required shall be reduced by 15°F for each increment of 10 ksi above 85 ksi. Yield strength is the value given in the mill test report.

 

4152.03 Shear Connector Studs

 

A.   Comply with ASTM A 108 for steel bars, carbon cold-finished, standard quality, Grades 1010 through 1020 inclusive either semi-killed or killed deoxidation. Inspection and acceptance of shear connector studs will be according to Materials I.M. 453.10.

 

B.    Provide an arc shield (ferrule) of heat-resistant ceramic or other suitable material when approved by the Engineer. Ferrules shall be kept dry and protected from moisture or oven dried at 250°F for 2 hours.