Experimental study on the dynamic modulus of compacted loess under bidirectional dynamic load  

作　　者：Liguo Yang Shengjun Shao Qilong Sun Ping Wang 

机构地区：[1]Institute of Geotechnical Engineering,Xi0an University of Technology,Xi0an,710048,China [2]Department of Civil and Traffic Engineering,Yellow River Conservancy Technical Institute,Kaifeng,475003,China [3]Shaanxi Key Laboratory of Loess Mechanics and Engineering,Xi0an University of Technology,Xi0an,710048,China

出　　处：《Earthquake Research Advances》2022年第3期58-66,共9页地震研究进展（英文）

基　　金：the National Natural Science Foundation of China(No.41272320,52108342);the Key Scientific Research Projects of Higher Education Institutions in Henan Province,China(No.21A560009).

摘　　要：The dynamic characteristics of compacted loess are of great significance to the seismic construction of the Loess Plateau area in Northwest China,where earthquakes frequently occur.To study the change in the dynamic modulus of the foundation soil under the combined action of vertical and horizontal earthquakes,a hollow cy-lindrical torsion shear instrument capable of vibrating in four directions was used to perform two-way coupling of compression and torsion of Xi'an compacted loess under different dry density and deviator stress ratios.The results show that increasing the dry density can improve the initial dynamic compression modulus and initial dynamic shear modulus of compacted loess.With an increase in the deviator stress ratio,the initial dynamic compression modulus increases,to a certain extent,but the initial dynamic shear modulus decreases slightly.The dynamic modulus gradually decreases with the development of dynamic strain and tends to be stable,and the dynamic modulus that reaches the same strain increases with an increasing dry density.At the initial stage of dynamic loading,the attenuation of the dynamic shear modulus with the strain development is faster than that of the dynamic compression modulus.Compared with previous research results,it is determined that the dynamic modulus of loess under bidirectional dynamic loading is lower and the attenuation rate is faster than that under single-direction dynamic loading.The deviator stress ratio has a more obvious effect on the dynamic compression modulus.The increase in the deviator stress ratio can increase the dynamic compression modulus,to a certain extent.However,the deviator stress ratio has almost no effect on the dynamic shear modulus,and can therefore be ignored.

关 键 词：Bidirectional dynamic load Compacted loess Dynamic modulus Dry density Deviator stress ratio Ground treatment 

分 类 号：TU41[建筑科学—岩土工程]