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| Wetting deformation characteristics of unsaturated sandy loess under complex hydro-mechanical paths |
| CAI Guoqing1,2,HAN Bowen2,WEI Jingwei2,LI Jian2,ZHAO Chenggang2 |
| (1. Key Laboratory of Urban Underground Engineering of Ministry of Education,Beijing Jiaotong University,Beijing 100044,China;2. School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China) |
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Abstract In order to study the wetting-induced deformation characteristics of unsaturated sandy loess under complex hydro-mechanical paths,the single-line triaxial wetting tests of the two complex hydro-mechanical paths of consolidation-loading-wetting-loading and consolidation-unloading-wetting-unloading under deviator stress are carried out by GDS unsaturated triaxial apparatus for unsaturated sandy loess. The effects of hydro-mechanical path and stress ratio on the wetting-induced deformation characteristics of unsaturated sandy loess are comprehensively analyzed. The research results indicate that:(1) Both the axial strain and the wetting shear strain decrease with the increase of stress ratio. (2) When the stress ratio is 0.25,the specimen fails to reach saturation,and then the dilatancy failure occurs. The wetting shear strain and void ratio of the specimens that experienced the loading path develops faster than that experienced the unloading path,and are the first to reach failure. (3) When the stress ratio is 0.5 and 0.75,the wetting deformation characteristics are basically the same. The wetting volumetric strain and moistening shear strain both increase first and then become stable with the increase of the wetting parameters. The void ratio first decreases and then becomes stable with the increase of the wetting parameters. The maximum wetting volumetric strain,wetting shear strain and the initial void ratio before the moistening of the samples that experienced the loading path are all greater than that experienced the unloading path.
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