摘要
以陕西省白鹿原地区的红黏土为研究对象,对其进行控制基质吸力的非饱和红黏土蠕变试验。对比了不同基质吸力、不同净围压和不同偏应力水平下的蠕变试验曲线特征,采用应力-应变等时曲线法和稳态蠕变速率法确定了红黏土不同基质吸力和围压下的长期强度并对其进行分析,采用摩尔-库仑强度模型得到了红黏土长期强度参数,并与相同基质吸力下剪切强度参数进行了对比分析。研究结果表明:红黏土的蠕变变形形式和长期稳定性与基质吸力和围压均有关系,且基质吸力和围压越高长期稳定性越好。当基质吸力固定不变时,红黏土的长期强度值随围压的增大而增大,并呈线性变化;当基质吸力不同时,红黏土长期强度与其基质吸力的大小成正比;因外部荷载长期作用而形成的蠕变变形会较大地降低红黏土原有的强度参数值。
In this paper,the creep test of unsaturated red clay in Bailuyuan area of Shaanxi Province is carried out.The characteristics of creep test curves under different matric suctions,net confining pressures and stress levels are compared.The long-term strength of red clay under different matric suctions and confining pressures is determined and alynize by stress-strain isochronal curve method and steady-state creep rate method.The long-term strength parameters of red clay are obtained by using the Mohr-Coulomb strength model and are compared with the conventional strength parameters under the same matric suction.The results show that the creep deformation form and long-term stability of red clay are related to the suction and confining pressure,and the higher the suction and confining pressure,the better the long-term stability.When the matric suction is fixed,the long-term strength of the red clay increases with the rise of confining pressure and changes linearly.When the matric suction veries,the long-term strength of rock and soil is proportional to the matric suction.The creep deformation caused by long-term external loads will greatly reduce the original strength parameters of rock and soil.
作者
王潇
Wang Xiao(Shannxi Testing Institute of China Geological Exploration Center of Building Materials Industry,Xi'an 710003,Shaanxi)
出处
《工程建设》
2020年第1期12-18,共7页
Engineering Construction
关键词
非饱和红黏土
基质吸力
蠕变曲线
等时曲线法
稳态蠕变速率法
长期强度
unsaturated red clay
matric suction
creep curve
isochronic curve method
steady state creep rate method
long-term strength
