Determining yield stress ratio and constrained modulus of volcanic soil in Kediri by using SPT

Abstract

Pre-consolidation pressure has been commonly used to describe the maximum stress that has been experienced by the soil and has been successfully implemented for sedimentary soils. However, a number of researched have shown that the term pre-consolidation pressure is not appropriate for residual soils and another term such as yield stress is coined as a more generic term. Yield stress is not only affected by the maximum stress that has been experienced by the soil but also by the bonding and structural alteration that might occur due to the weathering process. Hence, the value of yield stress depends on the origin and the weathering process that is experienced by the residual soil. In this research, data from oedometer and standard penetration test conducted at Kediri’s residual soil are collected and correlation between SPT-N value, yield stress and constrained modulus are proposed.