Effects of elevated temperatures on mechanical properties of concrete containing haematite evaluated using fuzzy logic model

Abstract

Concretes containing different proportions of haematite (15, 30, 45 and 60%) were fabricated and subjected to elevated temperatures (25, 200, 400, 600 and 800°C). The cement content and water/cement ratio were 450 kg m−3 and 0·38 respectively. The compressive strength and elasticity modulus of concretes were determined according to ASTM C39 and ASTM C469. A rule based Mamdani type fuzzy logic model for predicting the compressive strengths and elasticity modules of concretes containing haematite has been developed. The inputs were haematite content (%), exposure time (h) and temperature T (°C); the outputs were compressive strength and compressive elasticity modulus. It is shown that all the results of the model for elasticity modulus and compressive strength were in good correlation with the experimental results for all data sets.