Integrated modelling and design of reinforced concrete linings for tunnels

摘要

The structural design of permanent reinforced concrete linings of tunnels involves significant uncertainties, principally related to the simplistic representation of the concrete structure interaction with the surrounding geological medium and the inherent limitations pertaining to direct application of standard limit state design concepts. Notably, the characteristic of nonlinear structural behaviour of concrete is rarely considered in a rigorous manner. Geo-materials are often represented simplistically, including discontinuous rock masses which may still be approached as pseudo-continua. This paper reports on an integrated modelling approach allowing for the variable stiffness behaviour of reinforced concrete at different stages of flexural cracking and the effects of creep in interaction with discontinuous rock surround. The concrete behaviour model was implemented in the Universal Distinct Element Code (UDEC) and demonstrative results from modelling cases will be presented.