刚性挡土墙后轻量土静止土压力特性模型试验研究  

Model tests on earth pressure at rest of light weight soil behind rigid retaining walls

作　　者：侯天顺[1] 张建成 舒博 HOU Tianshun;ZHANG Jiancheng;SHU Bo(College of Water Resources and Architectural Engineering,Northwest A&F University,Yangling 712100,China)

机构地区：[1]西北农林科技大学水利与建筑工程学院,陕西杨凌712100

出　　处：《岩土工程学报》2024年第4期764-773,共10页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(51509211);中国博士后基金项目(2016M602863);陕西省留学人员科技活动择优资助项目(2018031);陕西省社会发展科技攻关项目(2015SF260);陕西省博士后基金项目(2017BSHYDZZ50);西安市岩土与地下工程重点实验室开放基金项目(XKLGUEKF21-02);陕西省自然科学基金项目(2024JC-YBMS-354)。

摘　　要：为了研究轻量土对挡土结构物的减压机理,通过开展大比尺刚性挡土墙模型试验,采用重物堆载的方式在填土表面施加均布荷载,分析重塑黄土和轻量土作为墙后填土时的静止土压力分布规律。结果表明:轻量土在养护阶段的静止土压力随着时间增长而逐渐增大,但增幅逐渐降低。重塑黄土和轻量土的静止土压力随着填土深度增加近似线性增大,并且静止土压力随着加载而逐渐增大,其中重塑黄土的增幅明显偏大。对比重塑黄土和轻量土的静止土压力,发现轻量土具有明显的减压作用,且填土表面均布荷载越大,轻量土的减压效果越好。重塑黄土和轻量土的静止土压力系数均不是常数,其中重塑黄土静止土压力系数为0.34~0.78,轻量土静止土压力系数为0.22~0.55。当填土表面作用均布荷载时,传统理论在计算重塑黄土静止土压力方面适用性较高,但轻量土计算误差较大。结合模型试验以及传统理论,提出了适用于轻量土的静止土压力修正公式,对比发现其相对误差总体上介于1.01%~23.13%。通过模型试验和理论计算揭示了轻量土的静止土压力特性,对于完善轻量土土压力理论具有重要意义。To study the reduction mechanism of earth pressure on retaining wall for light weight soil,the model tests on a large-scale rigid retaining wall are conducted.The uniform loads are applied on the filling surface by heavy stacking.When the remolded loess and light weight soil are used as backfilling behind the wall,the distribution laws of earth pressure at rest are analyzed respectively.The results show that the earth pressure at rest of the light weight soil gradually increases with the increase of curing period,but the increase range gradually decreases.The earth pressures at rest of the remolded loess and the light weight soil increase approximately linearly with the increase of filling depth.Moreover,they gradually increase with the increase of the upper loads,and the increase range of earth pressure at rest for the remolded loess is obviously larger than that of the light weight soil.By comparing their earth pressures at rest,it is found that the light weight soil has an obvious pressure reduction effect,and the greater the uniform loads applied on the filling surface,the better the pressure reduction effects of the light weight soil.The coefficient of earth pressures at rest of the remolded loess and light weight soil is not constant.The range of coefficient of earth pressure at rest for the remolded loess is 0.34~0.78,and that of the light weight soil is 0.22~0.55.When the uniform loads are applied on the surface of the filling,the traditional earth pressure theory has a high applicability to calculate the earth pressure at rest of the remolded loess,but the calculation error of the light weight soil is larger.Based on the model tests and traditional earth pressure theory,a modified formula for the earth pressure at rest for the light weight soil is proposed.It is found that the relative error is mainly 1.01%~23.13%.The characteristics of earth pressure at rest of the light weight soil are revealed through the model tests and theoretical calculation,which is of great significance to improving the earth pre

关 键 词：轻量土 静止土压力 静止土压力系数 修正公式 模型试验 

分 类 号：TU43[建筑科学—岩土工程]