Assessment of the effects of internal drainage on the design of tunnels

摘要

There is no universally accepted procedure for taking into account the effects of groundwater upon tunnels. Numerical models are employed herein in an attempt to better understand the advantages and disadvantages of draining a tunnel below ground-water. The adopted models are validated by comparison with published results (experimental, analytical and numerical) and with an analytical solution developed by the authors. Numerical and analytical results are compared in terms of rates of water inflow,axial forces and bending moments in tunnel lining. The benefits of draining the tunnel can be assessed, in terms of lining design, by means of the results presented herein, which also allow estimates of rates of infiltration for the analysed situations.