Effects of ground basaltic pumice and high temperatures on the properties of HSMs

Abstract

The mechanical and microstructural properties of high strength mortars (HSMs) containing ground basaltic pumice (GBP) subjected to 25, 300, 600, 900 and 1050 °C temperatures are investigated in this article. The mortars containing GBP employing the replacement ratio up to 25% GBP by weight of ordinary Portland cement (OPC) as well as a control mortar manufactured with OPC are produced. Two different cures, which are steam curing and pochette curing, are applied to the fresh mortars produced. The unit weight (ρ), ultrasonic pulse velocity (Upv), flexural strength (fs) and compressive strength (fc) of mortars containing GBP are investigated at the short/long terms and high temperatures. The microstructural properties of mortars containing GBP at high temperatures are also investigated by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDAX) analyses. The results have shown that GBP can be successfully used instead of OPC in the mortar mixtures. Especially, the steam curing application has improved the mechanical properties of mortars containing GBP better than those of pochette curing.