Differential Settlement due to Ground Fissures in Xi’an

Abstract

From 1950s 13 NEE ground fissures have been found in the suburb and downtown area of Xi’an city. Ground fissures bring harm to the Xi'an municipal construction, especially to the subway construction. By dynamic characteristics of Xi’an ground fissures, factors influencing differential settlement are analyzed and a conclusion is drawn that exploitation of ground water and the differential clay thickness on both sides of ground fissures is the governing factor. The amount of differential settlement in the following 50 years is predicted by ground-water Model and Verhulst Model. Good agreement is shown between these results. It leads us to suggest that the differential settlement will cut off the subway tunnel in the future and actions must be taken in the design phase of subway tunnel.