Effects of fly ash content and initial temperature of concrete mixture on thermal distribution of mass concrete

Abstract

The occurance of thermal cracks is quite common in mass concrete structures. Therefore, the design and selection of material input parameters to prevent thermal cracks play an important role. The paper presents the influence of fly ash (FA) content and initial temperature of concrete mixture on the maximum temperature in concrete samples with using both experimental method and numerical model. Three experimental samples: M1 (100% OPC), M2 (70% OPC and 30% FA), and M3 (50% OPC and 50% FA) are used. The obtained results show that, When the fly ash content is high, the amount of heat released in the samples is significantly reduced and the time of reaching the maximum temperature is slower than when using cement binders only. Besides, numerical models can be used to simulate and predict the maximum temperatures in concrete samples M1, M2, and M3 with high reliable results comparing to that of experimental method. The research results can be used as a reference in design to prevent thermal cracking in mass concrete structures.

Keywords: Thermal cracking; mass concrete; cement hydration; fly ash; maximum temperature.