Static Behavior of Reconstituted Soft Soil in Different Maximum Past Pressure under Triaxial Test

Abstract

Soft soils are poorly stable soils. Usually found at shallow depths, the soil is often disturbed by sampling. In addition, the variability of soil properties such as moisture content, unit weight, maximum past pressure, and the contamination of organic matter in the shallow depth which makes test results unreliable. To reduce the variability of the soil’s initial properties. In this research, the kaolin clay was prepared by slurry consolidation method. Three different maximum stresses were applied to create a normally consolidated soil (OCR = 1) and two overconsolidated soil (OCR = 3, 5). After that samples were tested by a consolidated undrained triaxial test (CU test) under a constant 40 kPa of confining pressure. The sample preparation displayed that the variability of the initial soil properties can be controlled. From the shear test results, they were found that soil strength tends to increase as the OCR increases. Pore pressure in the soil mass decreased after the soil begins to expand and the value dropped greatly as OCR increases. In addition, the normalized shear strength estimation of kaolin soils showed that the obtained equation was close to that of low-plasticity silt.