Mechanical properties of cracked concrete under uniaxial tensile load

Abstract

Cracks have a serious impact on the safety of concrete structures, and the tensile behavior of concrete is the key to control generation and propagation of crack. To improve the safety of concrete structures, it is crucial to understand the mechanical properties of cracked concrete under uniaxial tensile load. In this article, dynamic tensile test and tensile test after different fatigue damage were conducted to investigate the mechanical properties of cracked concrete. First, the damage evolution law of cracked concrete under dynamic tensile load was investigated by means of $d_{\mathrm{CMOD}}$ ( $d_{\mathrm{CMOD}}$ : crack mouth opening displacement) control mode whereupon the relationship of stress–d_CMOD considering rates effect was obtained. Then, the change law of cracked concrete under uniaxial tensile load after fatigue damage was studied by analyzing four mechanical parameters including tensile strength, elastic modulus, critical displacement, and fracture toughness. The empirical formulas of the four parameters with numbers of fatigue cycles are given. Furthermore, acoustic emission technology was applied additionally.