DEPENDENCE OF TUNNEL DEFORMATION DUE TO ADJACENT PILE UNDER LOADING ON TUNNEL GEOMETRY

Abstract

With rapid urbanization, large number of tunnels with various dimensions have been
constructed for transportation and utility systems in many big cities. At the same time, the constructions of
infrastructures using a pile foundation system are also necessary in urban area. With limited space, the
existing tunnels can be inevitably impacted by the newly constructed pile-supported structures. With various
design criteria of tunnel lining, the size and thickness are varied from project to project. With an adjacent pile
under loading, different degrees of impact on these tunnels are expected. This study numerically investigates
the effect of tunnel diameter and lining thickness on tunnel deformation due to adjacent pile under loading.
The MRTA and WMA tunnels in Bangkok subsoil are chosen as the reference cases for investigation. From
a series of parametric study, a relationship between the tunnel deformation and dimensionless parameter,
which include the size and thickness of lining, can be successfully established.