风化岩层中考虑拉压模量转换的基坑变形计算  

Deformation calculation of foundation pit considering tensile modulus transformation in weathered rock

作　　者：王更峰[1] WANG Gengfeng(China Railway 11 Bureau Group Co.,Ltd,Wuhan 430061,China)

机构地区：[1]中铁十一局集团有限公司

出　　处：《铁道科学与工程学报》2019年第8期1971-1978,共8页Journal of Railway Science and Engineering

基　　金：国家重点研发计划资助项目(2018YFC0808705)

摘　　要：针对风化岩层的不同模量以及与位移有关岩土压力,研究基坑工程岩土体变形计算问题。考虑到风化岩体的拉压不同模量,结合平面应变的物理方程和几何方程,建立平面应变问题的本构方程;基于Melan解,考虑不同模量问题与岩土压力和位移的关系,得到一种能够充分考虑基坑宽度、开挖深度、围护结构埋深以及岩土体应力状态的位移解析解,并将所得的理论计算结果应用于工程实际中,验证该计算方法的可行性和实用性。研究结果表明:随着岩土体拉压模量差值的增大岩土体变形越大,初始位移值与岩土体位移成正比。结果可为基坑工程围护结构的设计计算提供理论依据。Aiming at different modulus of tension and compression and earth pressure of weathered rock stratum,the deformation calculation of foundation pit engineering was studied.Considering the different modulus of tension and compression of weathered rock mass,the constitutive relation of plane strain was established by combining the physical equation and geometric equation of plane strain.Based on Melan solution,considering the relationship between different modulus and earth pressure and displacement,an analytical solution of displacement was obtained,which could fully consider the width of foundation pit,excavation depth,embedment depth of retaining structure and stress state of soil.The theoretical calculation results were applied to engineering practice,which verified the feasibility and practicability of the calculation method.The influence of different modulus of tension and compression of weathered rock mass and displacement of supporting structure after foundation pit excavation on deformation of rock mass was analyzed.It is concluded that the larger the difference of modulus of tension and compression of weathered rock mass is,the larger the deformation is,and the initial displacement is proportional to the displacement of soil body.It provides a theoretical basis for the design and calculation of retaining structure of foundation pit engineering.

关 键 词：深基坑 应力状态 位移解 拉压不同模量 Melan解 

分 类 号：TU433[建筑科学—岩土工程]