Investigation on the resilient modulus of soil mixture at various water contents and coarse grain contents under train moving loads  

作　　者：Yu SU Yue ZHANG Junyi DUAN Jianglin GAO Zhongzheng WANG Da LIU Bo HAN Wenzhe ZHU 

机构地区：[1]School of Infrastructure Engineering,Nanchang University,Nanchang 330031,China [2]Jiangxi Provincial Technology Innovation Center for Ecological Water Engineering in Poyang Lake Basin,Jiangxi Academy of Water Science and Engineering,Nanchang 330029,China [3]School of Mechanical,Medical and Process Engineering,Faculty of Engineering,Queensland University of Technology,Brisbane QLD 4001,Australia

出　　处：《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》2024年第12期1006-1017,共12页浙江大学学报(英文版)A辑(应用物理与工程)

基　　金：supported by the Jiangxi Provincial Natural Science Foundation of China(Nos.20224BAB214063,20224BAB214064,and 20232BAB204083);the National Natural Science Foundation of China(Nos.52208347 and 52208348);the China Postdoctoral Science Foundation(No.2023M731436);the Key Projects of Jiangxi Provincial Department of Water Resources(No.202426ZDKT01).

摘　　要：Interlayer soil in railway substructures is characterized by a fine/coarse soil mixture.Considering that the resilient modulus M_(r) of the mixture is influenced by the microstructure of fine soil,it is worthwhile to investigate this aspect further.In this study,the microstructure of fines was explored by mercury intrusion porosimetry(MIP),and its influence on the M_(r) of the mixture was studied by multi-stage dynamic triaxial tests with varying deviator stress amplitudesσ_(d).The results showed a fine matrix fabric obtained at water contents of fine soil w_(f)=17.6%and 13.7%(>the plastic limit of fine soil w_(p)=12%),and a fine aggregate fabric identified at w_(f)=10.6%(<w_(p)=12%).Interestingly,the influences of w_(f) andσ_(d) on the M_(r) of the mixture were observed:the rise inσ_(d) contributed to a decline in M_(r) when w_(f)>w_(p) but to an increase in M_(r) when w_(f)<w_(p).It was concluded that,for the fine matrix fabric(w_(f)>w_(p)),increasingσ_(d) induced a reduction in M_(r),while for the fine aggregate fabric(w_(f)<w_(p)),increasingσ_(d) gave rise to the growth of M_(r).The distinct M_(r)-σ_(d) behaviors for these two fabrics were explained by the competing influences between soil hardening upon loading and soil rebounding upon unloading.For the fine matrix fabric(w_(f)>w_(p)),considering its high deformability,the rebounding effect on M_(r) outweighed the hardening effect,and thus a decline in M_(r) occurred with the growth ofσ_(d).Conversely,for the fine aggregate fabric(w_(f)<w_(p)),the rebounding effect on M_(r) was secondary compared with the hardening effect based on the consideration of its low deformability,and thus an increase in M_(r) was observed with risingσ_(d).

关 键 词：Railway engineering Resilient modulus Unsaturated soil MICROSTRUCTURE 

分 类 号：TG1[金属学及工艺—金属学]