Study on the Mechanism of Soil–Steel H-pile Interaction in Integral Abutment Jointless Bridges

Abstract

AbstractIn integral abutment jointless bridges (IAJBs), the steel H-pile was usually applied in bridges to absorb the horizontal cyclic deformation induced by ambient temperature or earthquake. In order to further study the mechanism of interaction between soil and steel H-pile in IAJBs, several quasi-static tests on interaction of soil–steel H-pile under balanced earth pressure, soil–steel H-pile and soil–abutment–pile under unbalanced earth pressure were carried out. A comparative study was performed to find their behaviors in terms of horizontal deformation law, hysteretic curves, energy dissipation and skeleton curves. The test results indicate that the unbalanced earth pressure is impacted significantly on the horizontal deformation of pile. The horizontal deformation of HP specimen is basically symmetric under positive and negative loading. Its horizontal deformation gradually decreases along buried pile depth, then increases in reverse and finally decreases to zero at bottom of pile. For UHP specimen, the horizontal deformation of UHP model is asymmetric. Among them, the horizontal deformation gradually decreases along buried pile depth, then increases to maximum in reverse and finally decreases along buried pile depth under positive loading. The law of horizontal deformation is similar to HP model under negative loading. However, the horizontal deformation law of AHP model is complicated. Its horizontal deformation is between HP model and UHP model. The test results also indicate that the hysteretic curves of HP model are plump and symmetrical. The hysteretic curve of AHP model is significantly asymmetrical. In addition, the bearing and energy dissipation capacity of AHP model is the highest, whereas the ductility is the lowest.KeywordsBridge engineeringIntegral abutment jointless bridgeSoil–structure interactionUnbalanced earth pressureHorizontal deformation