The investigation of the effect of ambient temperature on the fracture mechanism of concrete

In this study, the effects of the ambient temperature on the mechanical properties of the concrete have been investigated. 150x150x150 mm sized cubic samples, 100Ø200 mm cylindrical and 100x100x500 mm prismatic samples were prepared for the experiments. The water/cement ratio was 0,50 and cement content was 380 kg/m³ in all the concrete mixture in this study. The concrete samples which were kept in cure tank during 28 days, after the cure period all the samples were kept in laboratory environment for twenty four hours. Then the concrete samples were waited in different temperatures which are -30, -20, -10, 0, 10, 20, 30, 40 and 50 ºC in the oven and refrigerator during 24 hours. Afterwards ultrasonic pulse velocity measurement, schmidth hammer hardness test, compressive strength, flexural strength and split tensile strength of these concrete samples have been examined. The test results showed that, there is a significant effect of the temperature difference on the strength of concrete subjected different ambient temperatures. Compressive strength for concrete subjected at -30 ºC was 24,8% higher than concrete subjected at room temperature (20 ºC), and compressive strength for concrete subjected at 50 ºC was 7% lower than concrete subjected at room temperature. Keywords: Concrete, ambient temperature, mechanical properties of concrete.