A new concept for interpretation of building-excavation interaction in 3D conditions

Abstract

This 3D numerical study presents the factors affecting displacements and rotations induced by deep excavation in the vicinity of a tall building with an emphasis on the building parameters. An accurate model of a 31.2 m deep excavation with an adjacent 12-story building was used to validate the numerical modeling. Plane strain analysis of the excavation-induced deformations using building surcharge method proved the inadequacy of the surcharge method regardless of the building stiffness. Although the results of the equivalent beam method and the building structural method was in general conformity with each other, modeling structural details of the building showed better capability in capturing even local interactions of the building and the excavation. Parametric study in 3D conditions investigated effects of the buildings position and dimensions on displacement interaction by examining the development of a potential failure surface (PFS). The results showed that the building’s position and dimensions relative to the PFS as well as the building proximity to the excavation corner play decisive roles on determination of the excavation induced displacements/rotations and should be considered in the design of the excavation support system near buildings.