Experimental Investigation on the Low Cycle Fatigue Life of Piles

In this study, the low cycle fatigue tests are conducted to investigate the fatigue life of steel H-piles subjected to thermal induced cyclic strains/displacements. Review of literature revealed that there are few experimental research data on the low cycle fatigue performance of integral bridge steel H-piles. For this purpose, experimental studies on full scale steel H-pile specimens are conducted to simulate cyclic behavior of steel H-piles under thermal effects in integral bridges by considering the effect of axial load combined with large amplitude strain cycles with various amplitude levels. Using experimental test results, the effect of axial load level is investigated on the low cycle fatigue performance of integral bridge steel H-piles. It is observed that the effect of axial load on the low cycle fatigue performance of integral bridge steel H-piles are so important to reduce the bending stresses in the steel H-piles and also increase the low-cycle fatigue performance of steel H-piles at the abutments of integral bridges at the moderate strain amplitudes. Moreover, it is observed that at large strain amplitudes the effect of local buckling should be considered more than the effect of axial load on the low cycle fatigue life of steel H-piles at the abutments of integral bridges.