A multiscale homogenization approach for multiphysics lattice modeling of alkali-silica reaction in concrete: Upscaling coupled mechanics and mass transport

Alkali-silica reaction (ASR) in concrete produces mechanical responses that are highly sensitive to environmental conditions. Although multiscale modeling has shown promise in linking laboratory-scale ASR degradation to field-scale structural performance, a comprehensive theoretical framework for this connection remains underdeveloped. This study introduces a multiscale homogenization approach to upscale coupled mechanical and mass transport processes in ASR-affected concrete within a dual-lattice framework. At the aggregate level, ASR-induced expansion is represented by eigenstrain imposition within a micromechanics model, while at the macroscale, a representative volume element (RVE) formulation employs asymptotic expansion homogenization and coarse-graining method to upscale governing equations for momentum equilibrium and mass balance. The model is validated against the long-term performance of Fontana Dam, demonstrating its robustness in predicting damage evolution during hydration and ASR development. Simulation results highlight that the spatiotemporal progression of ASR-induced cracking is strongly governed by the anisotropic distributions of multiphysics fields under coupled mechanical and environmental conditions.