冻结兰州黄土变形和强度特性试验研究  

Experimental Study on Deformation and Strength Characteristics of Lanzhou Frozen Loess

作　　者：牛亚强[1] 赖远明[1,2] 王旭[1] 蒋代军[1] 刘德仁[1] 

机构地区：[1]兰州交通大学土木工程学院,甘肃兰州730070 [2]中国科学院寒区旱区环境与工程研究所冻土工程国家重点实验室,甘肃兰州730000

出　　处：《兰州交通大学学报》2016年第1期111-115,共5页Journal of Lanzhou Jiaotong University

基　　金：国家973资助项目(2012CB026102);国家自然科学基金(41230630)

摘　　要：通过对-6℃的冻结兰州黄土在1～15 MPa的围压范围内进行一系列的三轴试验,分析其变形和强度特性.研究发现,随着围压的增大,冻结兰州黄土的初始切线模量近似线性增大,当围压大于11 MPa时又随围压的增大近似线性减小,其应力-应变曲线既有应变软化又有应变硬化特征.根据Hoek-Brown强度准则及包络线理论,建立冻结兰州黄土的非线性强度准则,以描述冻土强度随围压非线性变化的现象.In order to study the deformation and strength behaviors of Lanzhou frozen loess,a series of triaxial compression tests have been conducted under confining pressure varying from 1MPa to 15 MPa at-6 ℃.The results show that the approximate linear of initial tangent modulus increases with the increase of confining pressure while it decreases when the confining pressure is more than 11 MPa,and the shape of the stress-strain curve presents both strain hardening and strain softening.Meanwhile,the nonlinear strength criterion is built based on Hoek-Brown strength criterion and the envelope theory to reflect the nonlinear relationship between strength and confining pressure.

关 键 词：冻结兰州黄土 变形规律 强度特性 试验研究 

分 类 号：TU445[建筑科学—岩土工程]