开挖速率对软黏土深基坑时间效应的影响分析

Analysis on Time Effect of Soft Clay Deep Foundation Excavation Under Different Excavation Rate

基于流固耦合的基本控制方程,编制了相应的可以考虑时间效应的程序,通过某深基坑的验算,对不同开挖速率、地表沉降和桩顶位移、桩后土体超孔隙水压和有效应力、应力路径变化情况进行了分析,结果表明开挖速率大的基坑其坑侧土体应力先达到土体的抗剪强度而破坏,建议在实际工程中易采用分层开挖的方法进行施工。

A program which is based on the governing equation of fluid-solid coupling has been completed to calculate deep foundation excavation. An engineering example of deep foundation excavation is taken for calculation. The effect of different excavate rate on surface settlement,displacement of pile top,excess pore-water pressure of the soil which behind the pile and effective stress were analyzed. The results show that the high excavation rate makes soil stress easy to reach the soil shear strength and failure,layered method of excavation should be adopted in practical engineering.