关键词: 基坑, 挡墙水平位移, 地表沉降, 微元法, 显式解析解

Abstract: The excavation-induced settlement of soil behind retaining wall is analytically deduced based on displacement boundary problem under plain strain condition. The analytical formula of ground settlement caused by the rigid movement or parabolic flexible movement of retaining wall is derived by the fundamental solution for ground settlement caused by rigid horizontal movement of retaining wall. If the retaining wall influences infinity, the analytical formula and the fundamental solution are in the same. The fundamental solution induced by rigid horizontal movement of retaining wall is used to verify the analytical equation. The solutions of integrated form under deformation conditions of rotation with respect to bottom, rotation with respect to top, triangle-bugling movement and parabolic flexible movement are also used to verify the analytical equation, respectively. The results are in good agreement. Finally, the analytical formula is applied to prediction of measured data in the field. The extent of application is illustrated by the comparison between the analytical equation and in-situ measured data. When the wall deflection is small, the proposed analytical equation can predict settlement well. When the wall deflection is large, the normalized settlement curves derived from the analytical equation can predict settlement anywhere behind retaining wall safely. The results prove that the proposed analytical equation is practicable.

Key words: deep excavation, horizontal movement of retaining wall, ground settlement, differential element method, explicit analytical solution