抄録
After tunnel excavation and lining installed, the excess porepressures around tunnel dissipate over time, thus changing thesoil effective stresses and leading to additional, time-dependentdeformations. The deformation of soil around the tunnel canchange the internal forces in lining. This study focuses on theeffect of boundary conditions of advance face and lining on theinternal forces in lining after tunnel excavation. The numericalmodel with specific geological conditions is established and thetunneling process is modeled by a step-by-step excavationusing ABAQUS software. Four different cases were consideredin the numerical model including permeable or impermeableboundary conditions of the lining and the advance face. Fromthe calculation result the change mechanism of the internalforces in the lining after tunnel excavation are obtained. Whenthe lining is impermeable the internal forces in the liningchanges a little after tunnel excavation and when the lining ispermeable the internal forces increased is dramatic. When theadvance face is impermeable the increased internal forces inthe lining are larger and when the tunnel is buried in largepermeably soil the internal forces in the lining will be constantafter tunnel excavation.
