Coupled Analysis of Reinforced Concrete Lining with High External and Internal Water Pressure

Abstract

Considering reinforced concrete lining often using in underground diversion tunnels as permeable media and combining concrete smeared cracking model, equivalent continuum porous saturated hydro-mechanical coupling model of lining is established based on generalized Biot’s theory. Reinforcement in concrete structures is typically provided by means of rebars which are embedded in the concrete. Then the model is applied to analyze lining structures of Jinping diversion tunnels during excavation and operation processes in which high external and internal water pressure would play a dominant role in affecting the behavior of lining respectively. Coupling research are carried out to analyze some important factors that would influence the hydro-mechanical behavior of lining and surrounding rock mass such as decreased orders of hydraulic conductivity magnitude of grouting zone, internal water pressure acting as body force and existing cracks in the lining, and the results shows that grouting zone of good quality and sufficient measurement for preventing the cracks from initiation and coalescence in the lining are important for the construction and operation of the diversion tunnels.