Paper Title
Relationship between Destructive and Non-Destructive Method of High Strength Concrete Made with Pyrophyllite Aggregate under High Temperature

In this study, compressive strength and ultrasonic pulse velocity (UPV) of high strength concrete (HSC) containing pyrophyllite aggregate (PA) were determined at elevated temperature (ranging from 150 to 750oC). It is aimed to improve the fire resistance of this concrete type by using pyrophyllite aggregate which is known to be resistant to fire. For this purpose, the aggregate in the concrete was substituted with 25%, 50%, 75% and 100% of pyrophyllite aggregate. Results showed that the compressive strength and UPV values of samples were decreased with an increase in PA ratios. In addition, with the increase of temperature, both compressive strength and UPV values of all samples decreased. There are many exponential relations between UPV and compressive strength for HSC blends produced with PA. The R2 values of the exponential relation equations were found above 0.90. Keywords - Compressive Strength, High Strength Concrete, High Temperature, Pyrophyllite Aggregate, Ultrasonic Pulse Velocity