摘要
为了研究涵侧填土对采用分离式基础涵洞地基承载力的提高效应,先结合基底土体的受力特点,进行受力分析,建立计算模型,构建求解分离式基础地基极限承载力的算法,给出承载力表达式。然后在相似理论的指导下,设计了5组模型,试验模拟粉质黏土地基受荷变形直到破坏的全过程,绘出荷载-沉降曲线,测得涵侧填土高度为0、4、8、12、16 m时的地基极限承载力。试验发现:随着侧填土高度的增加,承载力显著提高,当填土为12 m时已达到885 kPa;但提高幅度表现出非线性特性,先从18.42%增加到36.11%,然后减小到3.39%;当填土达到16 m时承载力达到915 kPa且不再增加;同时发现使用本文算法与试验实测值的误差小于10%,可以考虑用此算法计算分离式基础涵洞的地基极限承载力。继而得出结论:当涵洞地基沉降满足设计要求时,涵侧填土显著提高了地基承载力,节约工程造价,且提高的幅度先增加后减少,当达到16 m时地基承载力便逐渐趋于915 kPa。
Combining with the stress characteristics of the foundation soil,the soil force was analyzed for finding the improved effect on the separated foundation bearing capacity of lateral fill.Establishing the calculation model and algorithm,the general formulation of separated foundation bearing capacity considering lateral fill was deduced.Then under direction of similarity theory,five model tests were designed to simulate the foundation deformation of silty clay in whole loading process.The pressure-settlement curves were drew and the foundation bearing capacity under lateral fill height of 0 m,4 m,8 m,12 m,16 m were measured.Test results showed that with the fill height increasing the bearing capacity increased significantly,it had been reached 885 kPa when the fill height was 12 m.But the growth was nonlinear,it firstly increased from 18.42% to 36.11% and then reduced to 3.39%.At last the bearing capacity reached 915 kPa while fill height reached 16m.Meanwhile the errors between the calculated results and measured by model test were almost less than 10%,so the algorithm was feasible.The conclusion is that the lateral fill is advantageous for improve the foundation bearing capacity and reduce project cost significantly when the settlement of the culverts foundation satisfied the design request,with the lateral fill increasing,the rate of the improvement first increases and then decreases,at last it tends to 915 kPa when fill height reached 16 m.
出处
《吉林大学学报（地球科学版）》
EI
CAS
CSCD
北大核心
2011年第3期771-776,783,共7页
Journal of Jilin University：Earth Science Edition
基金
国家'973'计划项目(2010CB731503)
关键词
侧向填土荷载
分离式基础
地基承载力
模型试验
临界值
lateral fill
separated foundation
foundation bearing capacity
model test
critical point
作者简介
王雯璐（1983-），女，河南郑州人，博士研究生，主要从事公路桥涵的工程地质问题研究，E—mail；wangwenlu1983@163．com
通信作者：王磊（1968--），男，吉林长春人，教授，博士生导师，主要从事公路桥梁新型基础型式，复合桩基和复合地基等方面的研究，E-mail：wlei@jlu．edu．cn。
