Effect of high temperature on SCC containing fly ash

Abstract

The effect of high temperature on self-compacting concrete, which contains different amounts of fly ash, has been investigated. By considering the effect of concrete age and increased temperatures, the optimum fly ash-cement ratio for the optimum concrete strength is determined using experimental studies. Self-compacting concrete specimens are produced, with fly ash/cement ratios of 0%, 20% and 40%. Specimens were cured for 28, 56 and 90 days. After curing was completed, the specimens were subjected to temperatures of 20°C, 100°C, 400°C, 700°C and 900°C for three hours. After the cooling process, tests were performed to determine the unit weight, ultrasonic pulse velocity and compressive strength of the specimens. According to the experiment results, an increase in fly ash ratio causes a decrease in the compressive strength of self-compacting concrete. However, it positively contributes to self-compaction and strength loss at high temperatures. The utilization of fly ash in concrete significantly contributes to the environment and the economy. For this reason, the addition of 20% fly ash to concrete is considered to be effective.