A new method for estimation of undrained shear strength of cohesive soil for design use from CPTU

This paper presents a new method for estimation of shear strength of cohesive soil for design use su(mob) using CPTU results only. The su(mob) is estimated through a cone factor which is calculated by linear relational expression between net cone resistance and strength increment ratio on normally consolidated state which is determined by excess porewater pressure during cone penetration. The method is established based on the data obtained from 31 locations of 25 sites on Japanese, East Asian and South East Asian cohesive grounds. Reliability and applicability of the su(mob) obtained from the proposed method are verified by comparing with the su(mob) from various laboratory tests using undisturbed samples and in situ tests. The method can evaluate the su(mob) without a process associated with human error among boring, undisturbed sampling and laboratory testing.