An equivalent beam model for the analysis of tunnel-building interaction

The aim of this work is to study the effect of structural characteristics, including stiffness, geometry and weight on tunnel–adjacent structure interaction. Ground materials, tunnel geometry and excavator device are related to a part of metro tunnel of Tehran. To describe the ground behavior due to tunneling, a 3D FE code with an elastoplastic soil model was used. The adjacent building was modeled in two ways: one as an equivalent beam or shell and the other as a real geometry (3D frames). The obtained results from this theoretical work indicate particularly that the stiffness of adjacent structure controls the ground movement distribution induced by tunnel excavation which in agree with other researchers. As it was predicatively, increasing in structure weight leads to create the large displacement components in the ground. The structure width plays also a significant role in displacement distribution of ground. The comparison of the obtained results using two methods of structure modeling shows a very good conformity between them.

► Ground movement due to tunnel excavation is strongly affected by stiffness of adjacent structure.
► With the equivalent beam method, the stiffness of adjacent building can be simply modelled.
► If structural details are available, link of structural and geotechnical FE codes is proposed.