Study on the freezing–thawing deformation of consolidated soils under high pressure

作     者：DaYan Wang Wei Ma lele lei 

作者机构：LeLe LeiState Key Laboratory of Frozen Soil EngineeringNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China 

出 版 物：《Research in Cold and Arid Regions》 (寒旱区科学（英文版）)

年 卷 期：2017年第9卷第1期

页      面：29-37页

核心收录：

学科分类：07[理学] 08[工学] 080104[工学-工程力学] 0815[工学-水利工程] 0705[理学-地理学] 070501[理学-自然地理学] 0801[工学-力学（可授工学、理学学位）] 

基　　金：supported by a grant from the National Natural Science Foundation of China(No.41671069,No.41630636) Foundation of the State Key Laboratory of Frozen Soil Engineering(SKLFSE-ZT-31) 

主　　题：freezing-thawing deformation artificial ground freezing K0 consolidation high pressure 

摘      要：The freezing-thawing deformation behaviors of consolidated soils under high pressure have been investigated in a high-pressure-low-temperature （HPLT） Kq consolidation apparatus with a small strain sensor. The tests cover a variety of frozen soil temperatures ranging from -2℃ to -10 ℃, and a series of applied pressures ranging from 1 MPa to 5 MPa. The test results show that, for the consolidated soils under high pressure, their freezing-thawing deformation was caused by the realignment and the deformation of soil particles, the phase change of water, and the water redistribution in the soil. As for the deformation produced by thermal expansion and contraction,it is about 0.04-0.05 mm, accounting for only about 7%~9% of the total deformation. Taking the freezing-thawing deformation produced by temperature disturbance as a creep deformation, the creep models of the developing soil deformation will be determined by the soil＇s final temperature, i.e., the desired temperature. For the soils under a desired temperature between -2℃ and -5℃, the freezing-thawing de-formation develops according to a non-attenuation creep model; but for the soils with a desired temperature lower than -5℃, a full attenuation creep model is followed. The applied pressure and soil type also have a significant influence on the maximum freezing deformation. Generally, the greater the desired pressure applied, the less the maximum deformation is; and the loess freezing deformation is larger than that of sand.