三轴应力条件下泡沫轻质土压缩特性  

Compression Characteristics of Foamed Lightweight Soil under Triaxial Stress

作　　者：袁化强 朱登元 张宏庆 吴佳杰 徐茜茜 孙仁娟 YUAN Huaqiang;ZHU Dengyuan;ZHANG Hongqing;WU Jiajie;XU Xixi;SUN Renjuan(School of Qilu Transportation,Shandong University,Jinan 250000,China;School of Civil Engineering and Architecture,Linyi University,Linyi 276000,China;Shandong Hi-speed Group,Jinan 250000,China)

机构地区：[1]山东大学齐鲁交通学院,济南250000 [2]临沂大学土木工程与建筑学院,临沂276000 [3]山东高速集团有限公司,济南250000

出　　处：《硅酸盐通报》2020年第10期3379-3385,共7页Bulletin of the Chinese Ceramic Society

基　　金：山东省自然科学基金(ZR2016EEM03)。

摘　　要：为探究在复杂应力条件下泡沫轻质土的压缩特性,通过不固结不排水三轴压缩试验研究了三种不同湿密度的泡沫轻质土在多种围压状态下的应力-应变分布规律、抗剪强度特性和破坏形态。结果表明,泡沫轻质土的三轴压缩变形过程可划分为弹性变形-应变硬化-压密破坏三个阶段。同一湿密度泡沫轻质土的偏应力和峰值应变随加载围压增大均呈现先增大后减小规律。提高泡沫轻质土湿密度,降低孔隙率,能够增大其粘聚力及内摩擦角,粘聚力约为同龄期无侧限抗压强度0.34倍,实测轻质土侧向压力系数与理论计算值一致。轻质土试件破坏形态与其力学强度有关,可根据最终破坏形态分为剪切破坏和压密破坏两类。In order to explore the mechanical response law of foamed lightweight soil under complex stress state,the stress-strain distribution,shear strength characteristics and failure pattern of three different wet densities foamed lightweight soil under different confining pressures were studied through unconsolidated undrained triaxial test.The results show that the triaxial compression deformation process of foamed lightweight soil can be divided into three stages:elastic deformation,brittle fracture and compaction failure.With the increase of confining pressure,the deviational stress and peak strain of foamed lightweight soil with the same wet density increase first and then decrease.Increasing the wet density of foamed lightweight soil and reducing porosity can increase its cohesion and internal friction angle.The cohesion is about 0.34 times of the unconfined compressive strength of the same age specimens.The measured lateral pressure coefficient of foamed lightweight soil is consistent with the calculated value.Failure pattern of specimens is related to its mechanical properties,which can be divided into two types according to the final failure pattern:shear failure and compaction failure.

关 键 词：泡沫轻质土 三轴试验 应力-应变特性 抗剪强度 破坏形态 

分 类 号：U416.1[交通运输工程—道路与铁道工程]