Experimental Study of Concrete Meso-Damage Evolution Mechanism Based on Uniaxial Compression CT Method
单轴压缩条件下混凝土细观损伤演化机理的CT试验研究

Concrete is a heterogeneous material and may be considered as a three-phase composite consisting of aggregate, mortar and interface between aggregate and mortar from a mesoscopic view. The variation characteristics of CT average number were analyzed by CT scan images of meso-damage process, based on CT testing of concrete meso-damage evolution under unaxial compression. Concrete damage process may be divided into several stages, and the method of extracting the damage variable was proposed. Considering the experimentally obtained macro stress-strain curve, the relation between the damage variable and macro strain was obtained by data fitting. A new equation of damage evolution damage and a damage constitutive model were established. Through comparing and analyzing, the obtained theory results coincide well with the experimental results. So the concrete meso damage-fracture mechanism was deeply investigated.