Strain rate effect on structural steel under cyclic loading

The strain rate and strain rate history effects on the inelastic stressstrain behavior of annealed A-36 structural steel at room temperature are examined experimentally under monotonic and cyclic loading conditions. The strain rate used is between 10^-6-10^-1/sec, which covers the range that might be experienced by steel building frames during earthquake ground motions. An axial-torsional, electrohydraulic, servocontrolled testing system with strain control is used for all the tests. Test results show relatively more significant strain rate sensitivity of the material for monotonic loading and less significant strain rate sensitivity for cyclic loading. Strain rate hfstory effect is not significant in most of the tests.