An Analysis of the Impact Exerted on Bearing Capacity of Pier and Pile after Increasing Pile Cap Height

Abstract

An analysis was carried out in this paper on the bearing capacity of pier pile and seismic performance rule when the low-pile cap is increased by 1 meter, 2 meters, and 3 meters. The bottom of the pile cap of pier no. 11 of Minjiang River bridge faces three “lows”: 7.6 meters lower than island, 4.6 meters lower than natural river bed, and 6.5 meters lower than low water level. The numerical simulation method is adopted to input three seismic waves of Wolong, Bajiao, and EL to evaluate the bearing capacity of pier and pile under strong earthquakes. Using the standard formula and numerical simulation method, it is observed that the bending moment and axial force of bridge pier show an insignificant change under different seismic waves when the pile cap is increased by 0–3 meters. With peak ground acceleration increased to 0.35 g, the vertical bearing capacity and flexural capacity of pier and pile gratify the requirements; however, the pile foundation will be subject to compression and bending damage.