Continuum solutions for tunnel–building interaction and a modified framework for deformation prediction

Abstract

In this paper, the response of buildings to tunnelling-induced ground movements is studied with elastic and elastoplastic continuum solutions that consider the structure as an equivalent simple beam. A comparison is made between these simple solutions and centrifuge test data to provide insights into flexural and axial building deformations of low-rise bearing wall structures on strip foundations; the influence of wall openings and the foundation scheme on the equivalent beam bending stiffness is also addressed. Subsequently, the effects of structural continuity across greenfield sagging and hogging regions on tunnel–structure interaction are investigated. Finally, the continuum solutions are used to propose a modification factor formulation that accounts for the change in settlement trough shape (compared to the greenfield) due to soil–structure interaction. This formulation, for example, accounts for the change in transverse length of the hogging and sagging regions of a building due to soil–structure interaction, eliminating the need to divide the building at the greenfield inflection points when calculating modification factors. The proposed formulation, which is compared with numerical, experimental and field data from previous research, is shown to better predict flexural building deformations.