Abstract
A series of tests simulating the process from sampling to unconfined and triaxial compression tests for a highly organic soil consolidated under anisotropic stress condition were performed, and the influence of stress release and mechanical disturbance of specimen on the undrained strength is examined. A practical method for predicting in-situ undrained strength from the relationship between residual effective stress and unconfined compressive strength is proposed. From the test results, it is found that the effective angle of shear resistance is not influenced by stress release and mechanical disturbance exerted on the test specimen. It is also found that strengths detemined from unconfined compression tests can be reasonably corrected to estimate in-situ undrained strengths by applying a simplified method.
