Effect of High Temperature on Composite Mortars Containing Hazardous Expanded Polyvinyl Chloride Waste

Abstract

The disposal of hazardous wastes poses a serious threat to the environment because of their long period of degradation. This study is based on an experimental approach that aims to analyze the effect of high temperatures on the characteristics of lightweight masonry mortars incorporating expanded or cellular PVC (EPVC) aggregates from advertising and decorative display hazardous waste products. This article presents an experimental study of the physicomechanical and thermal properties of lightweight composite mortars based on expanded PVC (LMEPVCs) in which natural aggregates were replaced by EPVC aggregates at different mix proportions. The LMEPVCs were heated to temperatures of 450°C, 650°C, and 850°C. In addition, this study focused on the evolution of mass loss, apparent volume, porosity accessible to water, microstructure, mechanical strength, ultrasonic pulse velocity, dynamic elastic modulus, and thermal conductivity of various LMEPVCs as a function of applied temperature. The results obtained showed that these LMEPVCs retained their initial properties even after exposure to high temperatures; their properties were found to be similar to those of reference mortar. Moreover, the incorporation of 75% EPVC aggregates in the cement matrix revealed that the formulated composites had the capacity to resist thermal loads up to a temperature of 650°C. It was therefore concluded that the incorporation of EPVC in masonry mortars may be viewed as an environmentally friendly approach for recycling this type of nonbiodegradable waste.