Effects of internal erosion on mechanical properties evaluated by triaxial compression tests

Abstract

The aim of this research is to reveal the influence of internal erosion on mechanical properties by laboratory testing. Internal erosion is the transportation of fine particles with seepage flows inside the ground. A large degree of erosion induces various ground disasters, such as landslides and sinkholes. However, the influence of a small degree of internal erosion has not been examined. This is probably because the erosion progresses slowly, due to the repetition of seepage flows in the ground over a long period, without any obvious collapse or deformation. A new triaxial testing apparatus was developed in this study, that allows for a subtle amount of internal erosion inside the specimen. A field soil, containing around 10% clay, was used. Following the internal erosion, due to downward seepage, the specimen was monotinically sheared under a drained condition. LDTs and clip gages were mounted onto the specimen and the deformation characteristics were obtained during both erosion and monotonic shearing.