Experimental and numerical investigation on thermal properties of alkali-activated concrete at elevated temperatures

Abstract

his paper presents the experimental and numerical investigation on the thermal properties of steel fibre-reinforced alkali-activated concrete (AAC) made by using multiple precursors at elevated temperatures. The temperature-dependent thermal properties such as mass change, thermal conductivity, density, specific heat, and thermal expansion are reported. The effects of temperature heating AAC, coarse aggregate, and steel fibre on the thermal performance of AAC are evaluated quantitatively. Experimental results show that high temperature greatly affects the thermal properties of AAC. Coarse aggregate and steel fibre also have a considerable influence on the thermal properties. Based on the test results, a multi-phase mesoscale model is developed to predict the thermal properties considering volume fractions of steel fibre and coarse aggregate, which can be used in the fire safety design of AAC structures.