Impact of high temperature on mortar mixes containing additives

Abstract

The structures may be exposed to fire or high temperature conditionally or accidentally. Alteration in the behavior of concrete structure is prospective under the exposure of elevated temperature. There is an urge to find the materials which can resist the alteration in physiochemical and strength properties of cementitious materials under high temperature. In the present study, the effect of elevated temperature on cement mortar consisting of additives i.e. accelerating admixtures, and stone waste i.e. stone slurry powder, was investigated and compared with specimens at room temperature. The aim of study was to examine the practicability of these additives under exposure to high temperatures. The mortar specimens were exposed to various temperatures i.e. 1500C, 3000C, 4500C and 6000C for the duration of one hour and compared with unheated samples. The change in mass, strength and micro-structure of mortar specimens at elevated temperature was studied. The environmental assessment and performance evaluation of various mortar mixes were also evaluated. The mass of mortar specimens reduced as the exposure temperature of specimens was raised. The residual strength of mortar increased up to a certain temperature afterward, it decreased. Stone slurry powder and calcium nitrate can be used individually and in combination to resist thermal changes.