Laboratory study of mechanical properties of ordinary concrete under high heat consumption in hydraulic structures, along with validation by SEM and XRD tests

In this laboratory research, a mixing plan was made of ordinary concrete containing Portland cement type 2 with a grade of 500 kg / m3. Compressive strength, tensile strength and modulus of elasticity tests of concrete were performed on concrete samples at 90 days of processing age at 21 °C and 600 ° C. In order to further evaluate and validate the results, SEM and XRD tests were performed on concrete samples at 90 days of processing age. Application of heat in concrete samples caused a decrease in test results in this study. In this regard, in the concrete compressive strength test, the strength decreased from 64.92 to 37.45 MPa, which included a decrease of 42.31%. In the concrete tensile strength test, the strength decreased from 5.22 to 2.27 MPa, which included a decrease of 56.51%, and in the concrete modulus of elasticity test, the modulus of elasticity decreased from 33.73 to 12.24 gPa Which decreased by 63.71 percent. The results of SEM and XRD tests at 21 °C and high temperature, while coordinating with each other, overlapped with the results of other tests in this article.