948.1 948.2(d)
948.1DESCRIPTION —This work is the construction of overhead steel sign structures of the type indicated.
948.2MATERIAL —
critical in accordance with AASHTO Specifications ) for all pipe with nominal wall thicknesses greater than 1/2 inch. The actual yield strength for all pipe, per mill test report, is not to exceed 65,000 pounds per square inch.
1.a ASTM A53/A53M, Grade B, Type E or S; or ASTM A500, Grade B; or ASTM A106, Grade B
1.b API 5L, Grades B, X42 or X52; PSL2 with the following characteristics:
• No jointers allowed
• Do not use thermomechanical rolled or thermomechanical formed (grad e suffix M) pipe on monopipe structures.
• Process of manufacture: seamless, electric resistance welded, or longitudinal seam, submerged arc welded.
Provide supplemental CVN testing (Zone2, non -fracture critical, in accordance with AASHTO Specifications) for columns with nominal wall plate thicknesses greater than 1/2 inch. Provide a minimum internal surface (concave) bend radius at each press -break that is five times the wall thickness or 1 inch , whichever is larger. (Bends are parallel to direction of mill rolling). The dimension across the flats on fabricated press -break columns may not vary by more than 2% from the specified dimension. The fabricator is responsible for all fabrication adjustments that may be necessary to accommodate any dimensional variation .
non-fracture critical, in accordance with AASHTO Specifications) for tube wall thickness greater than 1/2 inch. If press -break columns are used, provide a minimum internal (concave) surface bend radius that is five times the wall thickness or 1 inch, whichever is larger. (Bends re parallel to direction of mill rolling).
size, process, and nondestructive testing. Shielded Metal Arc Welding (SMAW), Submerged Arc Welding (SAW), Gas