Sensitivity analysis on antiseismic capacity of bridge pile foundation

To explore the key parameters controlling the antiseismic capacity (or supply) of the high-rise pile cap foundation, a finite element model for such foundation lay in the uniform clay was built in the OpenSees finite element framework, and elastic-plastic static analyses were performed on the model. Meanwhile sensitivity analysis was performed on the model using second-order central difference method. The results of these analyses indicate that among some indices of the anti-seismic capacity of the high-rise pile cap foundations, the response sensitivity for the compressive strength of concrete is small, the response sensitivity for the tensile strength of reinforcements and the soil cohesive force are large, the response sensitivity for the core concrete section area is stable, and the time inerval of the finite difference taken as 10-2 order is reasonable. For the further dynamic reliability analysis of pile cap foundation, the tensile strength of reinforcements and the soil cohesive force should be treated as the important parameters affecting the system failure probability.