Prediction method for mechanical damage performance of concrete under thermal action

The invention discloses a method for predicting mechanical damage performance of concrete under thermal action. The method comprises the following steps: performing thermal damage detection on a to-be-detected concrete test piece; carrying out real-time dynamic scanning on the concrete test piece subjected to thermal damage detection, capturing geometric structure information in the test piece, and then carrying out three-dimensional reconstruction to obtain porosity P; performing a thermogravimetric test on the concrete test piece subjected to thermal damage detection to obtain carbonization parameters; carrying out uniaxial compression on the concrete test piece subjected to thermal damage detection, and testing the compressive strength and splitting tensile strength of the thermal damage test piece in a Brazilian splitting test; according to the obtained porosity P, the carbonization parameters, the compression resistance and the tensile strength, a concrete test piece mechanical property calculation model