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

The mechanical properties and failure mechanisms of lightweight aggregate concrete (LWAC) represent critical subjects of interest within the engineering domain. Moreover, the intricate relationship between its microstructure and macroscopic mechanical attributes stands at the forefront of academic investigation. This study leverages image processing technology to construct a microstructural model of LWAC. By extracting and processing information from sectional images of actual LWAC specimens, we establish a mesostructural model that authentically mirrors the characteristics of real lightweight aggregates. Utilizing a novel finite element approach, the base force element method, we conduct numerical simulations of uniaxial tensile, uniaxial compression, and three-point bending tests on LWAC. Initially, image processing technology facilitates the generation of beam specimens, alongside uniaxial compression and tensile specimens of LWAC, enhancing the simulation of the aggregate’s shape and its stochastic distribution. Subsequently, we numerically simulate a three-point bending test, followed by simulations of uniaxial compression and tensile tests. Analysis during loading reveals the specimen’s mechanical behavior and damage modes, which are then juxtaposed with corresponding experimental outcomes. This comparison validates the feasibility and accuracy of the micromodel established herein for analyzing the micromechanics of LWAC materials. The application of image processing technology heralds promising prospects in the realm of concrete mesoscopic damage analysis.