Durability of concrete made of limestone crushed aggregate under high temperature effect

Main objective of this study is to identify the change in physical and mechanical specifications of concrete made of limestone aggregate under high temperature effect.During this study, class C20 concrete has been produced by using limestone aggregate, CEM I 42,5 R cement and super plasticizer ingredient. Fresh concrete has been poured into 100*100*10 cm molding and a standardized cure has been applied to the prepared concrete for 14 days. On 28th and 90th days, 20, 150, 300, 500, 600, 700 and 800 ºC high temperature has been exposed to cylindrical Ø5*10 cm sized samples for 3 hours. Samples which have been exposed to high temperature were cooled in two ways, by air and water. Tests such as ultrasonic pulse velocity, capillary water absorption and compressive strenght have been implemented on those cooled samples.Finally, it was seemed that as heat increases, compressive strength, ultrasonic pulse velocity, of concrete decreases and capillary water absorption amount increases. On the other hand; it was found that compressive strength of the samples on 20, 150 and 300 ºC temperature which were cooled by air is higher than the samples which have cooled by water; ultrasonic pulse velocity of the samples on 20, 150 and 300 ºC temperature which were cooled by air is higher than ones which have cooled by water; and compressive strength of samples on 500, 600 and 700 ºC temperature cooled under water is higher than ones cooled by air, ultrasonic pulse velocity of the samples on 500, 600 and 700 ºC temperature, cooled under water is higher than ones cooled by air; and capillarity coefficients of samples cooled by air are more than samples cooled by water.