Simulation of Fracture Process of Lightweight Aggregate Concrete Based on Digital Image Processing Technology

The mechanical properties and failure mechanism of lightweight aggregate concrete (LWAC) is a hot topic in the engineering field, and the relationship between its microstructure and macroscopic mechanical properties is also a frontier research topic in the academic field. In this study, the image processing technology is used to establish a micro-structure model of lightweight aggregate concrete. Through the information extraction and processing of the section image of actual light aggregate concrete specimens, the mesostructural model of light aggregate concrete with real aggregate characteristics is established. The numerical simulation of uniaxial tensile test, uniaxial compression test and three-point bending test of lightweight aggregate concrete are carried out using a new finite element method-the base force element method respectively. Firstly, the image processing technology is used to produce beam specimens, uniaxial compression specimens and uniaxial tensile specimens of light aggregate concrete, which can better simulate the aggregate shape and random distribution of real light aggregate concrete. Secondly, the three-point bending test is numerically simulated. Thirdly, the uniaxial compression specimen generated by image processing technology is numerically simulated. Fourth, the uniaxial tensile specimen generated by image processing technology is numerically simulated. The mechanical behavior and damage mode of the specimen during loading were analyzed. The results of numerical simulation are compared and analyzed with those of relevant experiments. The feasibility and correctness of the micromodel established in this study for analyzing the micromechanics of lightweight aggregate concrete materials are verified. Image processing technology has a broad application prospect in the field of concrete mesoscopic damage analysis.