一种振冲碎石桩复合地基的沉降计算方法

摘要

对振冲碎石桩复合地基桩体和桩间土的变形与应力一应变关系进行研究.假设在荷载作用下,复合地基中桩体变形均匀,桩-土变形协调,推导出振冲碎石桩复合地基沉降计算公式为:ABκ2εhυ3+2ABκεhυ2+A (D2 +B) h2hυ = nh2PD2;利用牛顿迭代法解一元三次方程,可求得复合地基沉降.将本方法应用于沿海某大型储油罐工程,计算振冲碎石桩复合地基总沉降量为171.5 mm,实测沉降量为162.2 mm,计算结果与实测结果基本吻合,表明该方法有一定的实用性.%The deformation and stress-strain relations of piles and soils of vibro-replacement stone column composite foundation have been studied. Based on the assumption under loading action, the deformation of pile was uniformly and deformation of pile-soil was harmoniously, the settlement calculation formula of vibro-replacement stone column composite foundation was deduced: ABk2εh3ν+ 2ABhkεhv2 + A ( D2 + B) h2hv = nh2pD2. The settlement of composite foundation can be obtained using Newyon iteration method to solve simple cubic equation. Applied this method in a large oil storage tank engineering, the settlement calculation result of vibro-replacement stone column composite foundation was 171.5 mm, approximately agreed with the measured settlment (162. 2 mm), indicating this method had certain practicality.