Correlating strength and durability to time-temperature profiles of high-performance mass concrete

Abstract

The temperature rise in mass concrete usually leads to premature distresses and early-age cracking. This paper correlates the time-temperature profiles to the mechanical properties and durability of high-performance mass concrete (HPMC). Five types of cement having different specific surface areas (SSA) and granulated blast furnace slag (GBFS) replacement rates are tested. Thirteen thermocouples were inserted at various locations inside a 1-m3 formwork to record the rate of concrete temperature rise, maximum temperature (Tmax), and time needed to attain Tmax. The mechanical properties were characterized by the compressive and flexural strengths, while the durability was evaluated using the drying shrinkage, water permeability, and chloride migration. Experimental results showed that concrete containing fine cement exhibited better strength and durability, yet increased tendency to thermal cracks and drying shrinkage. The partial cement replacement by GBFS reduced the concrete rate of temperature rise and Tmax, which led to reduced shrinkage. Analytical correlations and multivariable linear regression models were developed to predict the effect of SSA, GBFS replacement rate, and 28-day heat of cement hydration on the time-temperature characteristics and durability of HPMC.