Numerical Modelling of Damage in Tunnels Subjected to Fire Exposure

Tunnel fires represent one of the extreme catastrophic scenarios which might result in loss of lives, property, disruption of economic activity, etc. There are no available design guidelines to quantify the damage in tunnels subjected to fire. Given the extremely costly and time-consuming nature of laboratory tests (full-scale/scaled), numerical modelling strategies are usually preferred for damage assessment studies on tunnels subjected to fire. They are generally based on multi-physics components such as heat transfer, mechanical deformations and moisture transport and work at various scales. Limited numerical frameworks are available, which explicitly explain multi-physics based theoretical developmental aspects of tunnels under fire and their potential implications. This paper provides a generalized summary of a multi-physics-based numerical modelling framework for tunnels under fire exposure. The summary includes identifying multi-physics components, formulation of governing equations, multi-physics coupling, discretization strategies, numerical solutions strategies and application aspects. The summary presented here can facilitate the generalized numerical problem formulation of tunnels under fire exposure, which can eventually culminate in applications such as performance-based design, design parameterization, etc.