Insulation Resistance Time Reference Curves for Specifying Passive Fire Protection for Modular Structures from Shipping Containers

Shipping containers are increasingly adapted for modern modular construction of both permanent and mobile low-cost civilian-use structures, with the diversity and interchangeability of their uses suggesting the need for container-based modular structures to conform to standard fire safety requirements, notably insulation and integrity. Multi-storey structures in city centres consisting entirely of modified shipping containers, or shipping containers fitted into structural frames, are becoming more commonplace. Full-scale fire tests are generally rather expensive and can be complemented with systematic numerical studies of fire resistance times offered by a range of passive protection configurations and thermal transport properties. Noting that standardised fire resistance ratings have three components (structural, insulation, integrity), this study specifically considers fire resistance times offered by passive fire protection configurations, by performing a series of time-dependent finite element heat transfer analyses of passively protected side panel configurations. A set of reference curves with which to determine insulation resistance times in the context of the ISO 834-1 standard fire curve is presented, specifically for use in the rational fire safety design of modular structures constructed from shipping containers. Negligible literature is currently available on fire resistance ratings of shipping container structures.