Laboratory and Field Exposures of Fire Retardant-Treated Plywood: Part 3—Modeling Exposure Relationships
Keywords:Fire retardants, strength, plywood, laboratory-to-field exposure correlation
AbstractOur understanding of how to relate laboratory-induced degradation data to real-world in-service performance of fire-retardant (FR) systems is currently limited because we are unable to correlate laboratory steady-state experiments with actual in-service field performance. Current studies have generally been limited to isothermal rate studies with selected model FR chemicals. Currently, no known direct comparison exists of matched sets of samples with one set exposed to high-temperature laboratory conditions and the other exposed for an extended period of time as traditionally used in North American light-framed construction. The objective of this study was to determine the relationship for FR model compounds between laboratory and field results based on strength-temperature-RH (moisture content)-FR chemical interactions. Two previous studies evaluated the effects of various exposures on bending strength properties and directly compared matched laboratory- and field-exposure samples. This study presents an empirical model to relate the differential effects of laboratory and field exposures on changes in mechanical properties for matched samples.
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