Horizontal bearing characteristics of the railway bridge piers on root-digging well foundations
As a novel variable section foundation,a root foundation can increase the vertical and horizontal bearing capacities of the caisson and pile foundations;however,its effect on the seis-mic performance of a digging well foundation remains unclear.To clarify the influence of roots on the bearing capacity characteristics of a pier on a digging well foundation,a pseudostatic test was conducted on a railway pier on a root-digging well foundation to examine the characteristics of its hysteretic and skeleton curves.By establishing a finite element model for use in this test,the in-fluence of different root parameters on the energy dissipation capacity and bearing capacity of the pier was discussed.The results show that roots can improve the bearing capacity of the pier on the digging well foundation by fully promoting the participation of the surrounding soil,and the bearing capacity increases nonlinearly with displacement load on the pier top.Test and numerical simulation show that the damage to the root-digging well foundation is mainly caused by the fail-ure of the soil around the foundation;however,the foundation is not damaged.The increase in the length of roots evidently improves the bearing capacity and energy consumption of the pier on the root-digging well foundation.Only when the spacing between the roots is greater than the root width does widening the roots obviously improve the bearing capacity and energy consump-tion of the pier.Increasing the number of roots obviously improves the bearing capacity of the pier.The effect of arranging roots at the bottom of the foundation is not weaker than that at the side wall,and the roots should not be near the soil surface when they are arranged at the side wall.The research results provide a scientific basis for the applications of root-digging well foun-dations in railway bridges in China.
root-digging well foundationpierbearing capacity characteristicspseudostatic testparameter analysis
国家科技期刊平台
NSTL
万方数据
维普
