The tensile and creep characteristics of two structural steels (ASTM A36 and CSA G40.12) and a prestressing steel (ASTM A421), all three used extensively in the building industry, have been investigated. Information is presented concerning the initial portion of the stress-strain curve, the ultimate and yield strengths, the elongation, the reduction of area, and the two stress-dependent creep parameters, Z and ε_to, for temperatures up to 1200 and 1300 F.

The tensile data obtained for ASTM A36 steel seemed to agree with other reported data. The G40.12 steel exhibited somewhat unusual tensile behavior at about 700 F. For the ASTM A421 steel the natural scatter of the test data overshadowed the effect of crosshead speed (0.02 to 0.75 in./min) at temperatures below 700 F.

Harmathy's creep model seemed fairly well applicable to all three steels, and Clauss' rule concerning the creep rupture time to the two structural steels.