不同地区饱和原状黄土静态液化特性试验研究  

Experimental Investigation of Static Liquefaction of Undisturbed Saturated Loess in Different Regions

作　　者：张一希 许强[1] 刘方洲 赵宽耀 赵程 修德皓 邹锡云 Zhang Yixi;Xu Qiang;Liu Fangzhou;Zhao Kuanyao;Zhao Cheng;Xiu Dehao;Zou Xiyun(State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,Chengdu 610059,China;Georgia Institute of Technology,Atlanta,GA USA 30318)

机构地区：[1]成都理工大学地质灾害防治与地质环境保护国家重点实验室,成都610059 [2]Georgia Institute of Technology, Atlanta, GA USA 30318

出　　处：《地质科技情报》2018年第5期229-233,共5页Geological Science and Technology Information

基　　金：国家自然科学基金重点项目(41630640);国家自然科学基金重大项目(41790445)

摘　　要：黄土因饱水静态液化而发生突发性失稳破坏,易造成人员伤亡和财产损失。按照颗粒级配的不同,中国黄土分为砂质、粉质和黏质黄土,不同区域的黄土具有不同的静态液化特性。利用GDS三轴试验系统,对陕西神木砂质黄土区(Q_3黄土)、甘肃黑方台粉质黄土区(Q_3黄土)和陕西泾阳黏质黄土区(Q_2黄土)原状饱和黄土进行了等向固结不排水三轴剪切(ICU)试验,研究了初始孔隙比和颗粒级配对原状黄土静态液化能力的影响。试验结果表明:①3个地区的饱和原状土的应力-应变关系均为软化型,在中低围压下泾阳饱和原状黄土不发生液化,仅表现出弱软化现象;②中低围压下,初始孔隙比是影响原状黄土静态液化的主要因素,高围压下,初始孔隙比的影响逐渐减小,颗粒级配成为影响原状黄土静态液化的主要因素。The frequent occurrence of sudden loess landslides triggered by static liquefaction threatens the local development.On the basis of grain size distribution,the Chinese loess is commonly classified into sandy loess,silty loess,and clayey loess.We find that the Chinese loess located in different regions has different susceptibility to static liquefaction.Based on the isotropically undrained shearing test（ICU）,the intact saturated sandy loess,silty loess,and the clayey loess were investigated to better understand the effects of initial void ratio and grain size distribution on the static liquefaction susceptibility.The results show that loess from three regions are strain-softening in the stress-strain relations,and under the middle and low confining pressure Jingyang saturated undisturbed sample only showed weak softening phenomenon.Under low to middle confining pressure,the initial void ratio is the main factor that affects the static liquefaction of undisturbed loess,and under the high confining pressure,the effect of initial void ratio gradually decreases and the grain size distribution becomes the main factor that influences the susceptibility of static liquefaction of intact loess.

关 键 词：黄土 孔隙比 颗粒级配 静态液化 

分 类 号：P642.11[天文地球—工程地质学]