Practical design, testing & verification guidelines for pre-cast segmental tunnel linings subjected to fire loading

This paper presents a practical 5-stage fire design procedure for bored pre-cast segmental tunnel linings subjected to an accidental fire load. A case study is presented with each stage discussed together with references to design assumptions, structural analysis, concrete mix design, fire test specifications and guidance on the review and interpretation of fire test results. Finally, the effects of progressive local deep spalling are investigated with a non-linear transient thermal-mechanical coupled finite element analysis. The spalling behaviour is modelled with the removal of elements during the analysis to match those recorded during fire tests.