Experimental study on mechanical properties of concrete under sub-high temperature cycles

Abstract

Nuclear power plant containment, large storage tank, industrial cooling tower and some industrial plants under high temperature will be subjected to the sub-high temperature cycles from normal temperature to ~200°C. To explore the durability of the structural concrete, this paper carried out the experimental research on the mechanical properties of concrete under the cyclic environment of normal temperature to sub-high temperature (below 200°C). The uniaxial compression test of different strength concrete was carried out. The axial compressive strength grade ranged from 20 MPa to 70 MPa, and the changes in the appearance feature of concrete with different strengths after different number of times of sub-high temperature cycles were recorded. The evolution rules of mechanical parameters such as Young’s Modulus, peak strength, peak strain, and Poisson’s ratio under temperature cycles are obtained through uniaxial compression tests. The influence of sub-high temperature cycle on the macroscopic mechanical properties of concrete was studied. Moreover, the prediction formulas of mechanical parameters such as strength, peak strain, and Young’s modulus under different number of sub-high temperature cycles were established according to the test data.