Investigating the Effect of High Temperatures on Long-term Compressive Strength of Self-Compacting Concrete Containing Powdery Binary Admixtures

Introduction of self compacting concrete has brought huge technological advances. Use of SCC facilitated the concrete placing between the rebars, without need of external vibration, and just through the weight of concrete itself. This paper investigated the effects of high temperature on hardened properties of self compacting concrete (SCC) containing powdery admixture. For this purpose, self compacting concrete control (non-pozolan) specimen of ACI 237R-07 mixed design has been used in accordance with instructions. First, in order to ensure the satisfaction of tolerance related to quality control of SCC in fresh mode; slump flow, L box, T50 and V funnel were performed. Then the hardened specimens containing various minerals admixture (metakaolin, fly ash. silica fume and zeolite) were 91 days old heated to elevated temperatures (300, 500, 700 0C) to evaluate mechanical properties. Furthermore the ultrasonic pulse velocity test as non-destructive methods to estimate the compressive strength of specimen is presented.