New model for compressive strength loss of lightweight concrete exposed to elevated temperatures

Abstract

This study proposes a new model for the residual compressive strength of structural lightweight concrete after exposure to elevated temperatures up to 1000 °C. For this purpose, a database of residual compressive strengths of fire exposed lightweight concrete was compiled from the literature. Database consisted a total number of 289 data points, used for generating training and testing datasets. Symbolic regression was carried out to generate formulations by accounting for various input parameters such as heating rate, cooling regime, target temperature, water content, aggregate type, and aggregate content. Afterwards, predictions of proposed formulation is compared to experimental results. Statistical evaluations verify that the prediction performance of proposed model is quite high.