多年冻土区L型挡墙水平冻胀效应计算方法与分析  

Calculation method and analysis of horizontal frost heave effect of L-shaped retaining wall in permafrost regions

作　　者：董建华[1,2] 吴晓磊 师利君 于小燕 何鹏飞 DONG Jian-hua;WU Xiao-lei;SHI Li-jun;YU Xiao-yan;HE Peng-fei(Key Laboratory of Disaster Prevention and Mitigation in Civil Engineering of Gansu Province,Lanzhou University of Technology,Lanzhou,Gansu 730050,China;Western Engineering Research Center of Disaster Mitigation in Civil Engineering of Ministry of Education,Lanzhou University of Technology,Lanzhou,Gansu 730050,China)

机构地区：[1]兰州理工大学甘肃省土木工程防灾减灾重点实验室,甘肃兰州730050 [2]兰州理工大学西部土木工程防灾减灾教育部工程研究中心,甘肃兰州730050

出　　处：《岩土力学》2022年第4期879-890,900,共13页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.51778275,No.52178335);中央引导地方科技发展资金项目(No.YDZX20216200001739);陇原青年创新创业人才(团队)项目(No.2020RCXM120);兰州市十大科技创新项目(No.2020-2-11);甘肃省知识产权局高价值专利培育和转化项目(No.20ZSCQ034);甘肃省基础研究创新群体项目(No.20JR10RA205)。

摘　　要：针对多年冻土区L型挡墙设计中水平冻胀力计算方法不完善的问题,基于利夫金地基模型及挡墙-土体之间的协同变形原理,分别建立了墙后有无换填土两种情况下的L型挡墙水平冻胀效应计算模型,利用叠加原理及有限差分法对所提出的计算模型进行了求解,并依托MATLAB自行编制了水-热-力耦合分析软件。结合工程实例,应用提出的L型挡墙水平冻胀效应计算方法得到的水平冻胀力值分别与现场实测值、修正土压力值、规范经验值及水-热-力耦合软件模拟值进行对比分析,结果表明:提出L型挡墙水平冻胀效应计算方法得到的水平冻胀力值与现场实测值及数值模拟值在大体趋势上吻合较好,修正土压力值、规范经验值低估了水平冻胀力对挡墙的作用;相比规范经验值及现场实测值,提出的L型挡墙水平冻胀效应计算方法得到的水平冻胀力沿墙高呈抛物线和梯形两种分布模式,更具有普遍性;通过多场耦合分析可知,所提出L型挡墙水平冻胀效应计算方法与水-热-力耦合方法得到冻胀力趋势相似,表明了计算方法的可行性,可为多年冻土区L型挡墙设计提供一定的理论支持和指导。In view of the imperfection of the calculation method of horizontal frost heaving force in the design of L-shaped retaining wall in permafrost area,based on the Lifking foundation model and the cooperative deformation principle between retaining wall and soil,a simplified calculation model of horizontal frost heave effect of L-shaped retaining wall with or without replacement soil behind the wall is established,and the proposed calculation model is solved by superposition principle and finite difference method.Furthermore,the water-thermal-mechanical coupling analysis software is developed by MATLAB.Combined with an engineering example,the horizontal frost heaving force obtained by using the proposed calculation method is compared with the field measured value,the corrected earth pressure value,the code empirical value and the simulation value of the coupling software.The results show that:(1)the horizontal frost heaving force obtained by the proposed calculation method is in good agreement with the field measured value and numerical simulation value,while the corrected earth pressure value and the code empirical value underestimate the effect of horizontal frost heaving force on the retaining wall;(2)compared with the code empirical value and field measured value,the horizontal frost heaving force obtained by the proposed calculation method presents two distribution modes of parabola and trapezoid along the wall height,which is more general;(3)the multifield coupling analysis shows that the frost heaving force trend obtained by the proposed calculation method is similar to the trend obtained by the coupling method,which indicates the feasibility of the calculation method and can provide some theoretical support and guidance for the design of L-shaped retaining wall in permafrost area.

关 键 词：L型挡墙 水平冻胀力 冻胀量 变形协调 有限差分法 

分 类 号：TU43[建筑科学—岩土工程]