Assessment of the proposed wildfire curves for housing design protection

Abstract

The need to protect structures from the hazards of wildfires remains an area requiring further investigation. In this context, this study focuses on the analysis of a novel approach for defining and implementing standardized wildfire curves (WC) for the fire safety design of dwellings at the wildland-urban interface (WUI). The primary objective is to introduce the proposed WC and evaluate its representativeness in comparison to real cases documented in the literature, thereby validating its applicability. Emphasis is placed on the development of realistic standard fire time-temperature curves for natural fuels such as trees, shrubs, and litter. An extensive literature review was conducted to collect the most relevant time-temperature datasets, spanning experimental research from the 1960s to the most recent studies in 2023. These datasets were obtained using thermocouple devices positioned at various heights within the fuel bed. The study incorporates data from field tests, laboratory experiments, and real-life wildfire incidents in Portugal and other countries. Additionally, the authors present temperature curves acquired in situ from wildfires they monitored. Furthermore, a case study involving an external wall composed of classical construction materials commonly used in Portugal is numerically analyzed using the proposed WC. The heat transfer analysis examines the temperature distribution and internal heat flux. The results indicate that the WC effectively represents the scenario in which the highest internal temperatures within a dwelling are observed, highlighting its potential applicability in fire safety design.