Compressibility of Shanghai Unsaturated Soft Soil

Abstract:

Based on onedimensional compression tests,compressionreboundcompression curve and the compression index and rebound index of Shanghai soft soil were obtained.At the same time,the influences of suction on the strength of the unsaturated soil were analyzed.Then the test results were simulated with Alonso elasticplastic model,and the preconsolidation pressure versus suction (loadingcollapse curve) curve was fitted.Results show that the compressibility of the soil decreases while the matric suction increases.For certain suctions,elg p curve clearly step phases in elastic,elasticplastic and rebound recompressed phases.With compression of unsaturated soil,the preconsolidation pressure decreases with suction decreases.There is a surface among pore ration,suction and vertical stress.

Key words:Shanghai soft soil; unsaturated soil; compression test; suction