Abstract Abstract:Research purposes: Based on the 1 to 12 times of dry-wet loop tests on disturbed and compacted samples of medium expansive soil for different loop paths, this paper discusses the relationship between shear strength, swelling ratio, swelling pressure and path of dry-wet loops, number of loops, to identifies the test conditions and circulation parameters of dry-wet loops, as well as to provide the basis for the analysis on slope stability of expansive soils. Research conclusions: (1)The dry-wet loop test on disturbed and compacted samples of medium expansive soil,the shear strength decreases with the increase of dry-wet loop times. After 5 dry-wet loops, the shear strength tends to stable.(2)The swelling ratio and swelling pressure of expansive soil are not reversible after dry-wet loops. With the increase of dry-wet loop times, the swelling ratio and swelling pressure decreases and tend to be stable after 5 dry-wet loops. Thus, 5 dry-wet loop can be used as the characteristic parameters for test under alternate dry-wet conditions.(3)The results of this study can be used as the standard test method for dry-wet loops and also can be used for the stability analysis of the soil slope.
CHEN Yong-ai,LIU Fu-chun,ZHANG Hui-ping. Shear Strength Test Study of Expansive Soil under Alternate Dry-wet Conditions[J]. Journal of Railway Engineering Society, 2017, 34(8): 34-39.