Flow Characteristics of Large-Scale Liquefaction-Slip of the Loess Strata in Shibei Tableland, Guyuan City,Induced by the 1920 Haiyuan M81/2 Earthquake  

作　　者：MA Xingyu WANG Lanmin WANG Qian WANG Ping ZHONG Xiumei PU Xiaowu LIU Fuqiang XU Xiaowei 

机构地区：[1]Key Laboratory of Loess Earthquake Engineering,China Earthquake Administration,Lanzhou 730000,China [2]Lanzhou Institute of Seismology,China Earthquake Administration,Lanzhou 730000,China [3]Department of Civil Engineering and Mechanics,Lanzhou University,Lanzhou 730000,China

出　　处：《Earthquake Research in China》2020年第4期469-481,共13页中国地震研究（英文版）

基　　金：Received on July 6th,2020;revised on September 14th,2020.This project is sponsored by the National Natural Science Foundation of China(U1939209,51778590);the Spark Program(XH20057).

摘　　要：Based on the dynamic triaxial liquefaction test of the loess samples which are taken from Shibei tableland,Guyuan City,Ningxia,China,the characteristics of dynamic strain,dynamic stress and pore water pressure are studied under cyclic loading.Triaxial shear test is conducted immediately after the sample reaches liquefaction point.During the test,the property of the liquefied soil is analyzed through fluid mechanics method,whereby the fluidity of the liquefied soil is represented by apparent viscosity.The results show that the fluidity of liquefied loess changes from“shear thickening”to“shear thinning”as the shear force continues,and the fluidity of liquefied loess is closely related to its structure.In addition,in the process of forming a new stable state,the apparent viscosity and deviant stress change with axial strain in a similar approach.When the sample reaches its stable state,it meanwhile shows a relatively stable apparent viscosity.According to the fluid mechanics and the law of conservation of energy,the slip distance of the liquefied soil is estimated,and the results are in good agreement with the field investigation results.

关 键 词：Saturated loess HYDRODYNAMICS LIQUEFACTION Apparent viscosity 

分 类 号：TU435[建筑科学—岩土工程] P315.9[建筑科学—土工工程] P642.22[天文地球—地震学]