Modeling evaluation for fire resistance design of rail car floor assembly

Abstract

This paper is prepared to report the engineering practice by a Chinese railcar manufacture in a railcar design process for a Metro system in U.S. The fire resistance of rail car floor systems is considered as one of the important fire protection features on the railcars operated in U.S., which provides fire separation between the equipment installed under the floor and the passengers insider railcar. In this study, a pragmatic approach was developed to numerically evaluate the fire resistance of rail car floor assemblies and provide insights for necessary design modifications. Finite element analysis (FEA) was applied to assess the fire resistance performance of a rail car floor assembly designed for a metro railway system in the U.S. An optimization algorithm was applied to obtain the thermal properties of intumescent coating. FEA analysis results were applied to assist the design modifications so that the floor assembly successfully satisfies the current requirement and passes the ASTM E119 fire resistance test. The FEA modeling details and heat transfer analysis results are presented. It is also shown that the model predictions agree conservatively well with the full-scale fire resistance test data.