Time‐dependent displacement of diaphragm wall induced by soil creep

This paper presents the time‐dependent performance of an well‐instrumented excavation case using the top‐down construction method. Studies show that this time‐dependent wall displacement is mostly likely due to undrained creep of clayey soils surrounding the excavation. In other words, soil creep may make significant contributions to diaphragm wall displacement and ground settlement in a deep excavation project in soft clay strata. The extra movement was found to be about 30% of the total displacement. This paper also presents a quantitative method to evaluate this creep effect. The essence of this method is to incorporate a time‐dependent soil modulus that can reflect the effects of soil creep. This method has been shown to give reasonable results in the field and the laboratory.