半岩半土地基不均匀沉降的变刚度复合地基方案研究

Study on project of variable stiffness composite foundation based on uneven settlement of half-hard and half-soft rock foundation

以延安市安塞区拟建住宅楼为工程实例,提出变刚度复合地基方案,借助有限元分析软件MIDAS GTS NX,对半岩半土地质条件下变刚度复合地基进行数值模拟,通过改变桩间土模量、桩体模量、桩距、桩长等设计参数对地基土沉降特性进行研究,并分析地基差异沉降判断变刚度复合地基的适用性。研究结果表明:变刚度复合地基可较好解决半岩半土地基的不均匀沉降问题,通过调节变刚度复合地基设计参数,可控制地基差异沉降在合理范围之内。

Taking a proposed residential building in Ansai District,Yanan as an example,a program of variable stiffness composite foundation is proposed. The variable stiffness composite foundation of half-hard and half-soft rock geological conditions is carried out by numerical simulation with the finite element analysis software MIDAS GTS NX. The settlement characteristics of foundation are studied by changing the design parameters of soil modulus,pile modulus,pile spacing,pile length and so on. The suitability of variable stiffness composite foundation is based on the study of differential settlement. The results show that differential settlement of half-hard and half-soft rock foundation can be solved by the variable stiffness composite foundation. The differential settlement can be controlled within a reasonable range by adjusting the design parameters of variable stiffn ess composite foundation.