Passive fire protection materials for process equipment: testing the properties and modeling the behavior for advanced performance analysis

Advanced analysis of the performance of Passive Fire Protection (PFP) materials requires an effort beyond the simplifications introduced in standardized approaches (e.g. ASTM E119, ISO 834, API2001, UNI10898) and the specificity of single (and expensive) real scale tests. The availability of reliable models for the fundamental material properties is required for simulating PFP behavior during fire exposure. In the present study, results obtained from the experimental assessment of a set of representative PFP materials are presented and discussed. The data were obtained at laboratory scale by the integration of several techniques: Thermogravimetric Analysis, Differential Scanning Calorimetry, thermal conductivity analysis by transient plane heat source (hot disc). The main degradation regions of the material were identified. Semi-empirical constitutive equations were developed for the description of the fundamental properties: thermal conductivity, density, porosity, thermal effects of the degradation reactions. Where necessary, apparent kinetic models were proposed to describe the change of material properties during fire exposure. A Finite Element Model (FEM) used these results for the simulation of the protection performance. The model predictions were compared with experimental temperature profiles from fire tests on slabs of selected fireproofing material, obtaining a good agreement and, thus, validating the applicability of the proposed approach.