朱为龙
河海大学
Cracking Analysis of Early-age Concrete with Chemo-Thermo-Hydro-Mechanical Coupling Peridynamics
Abstract: During the hardening process of early-age concrete, the combined effects of hydration reactions, heat exchange, moisture migration, mechanical deformation, and fracture generally lead to complex cracking phenomena, significantly compromising structural performance and durability. To address this issue, this study comprehensively considers dominant mechanisms, including hydration heat release, autogenous shrinkage, thermal diffusion and expansion, moisture diffusion, and evaporation, thereby establishing a chemo-thermo-hydro-mechanical coupling model for early-age concrete. Furthermore, a nonlocal peridynamic modeling approach is proposed, incorporating a bond stiffness evolution model that accounts for the influence of hydration degree, temperature, and humidity variations on the material's mechanical properties, thereby accurately characterizing the time-dependent mechanical behavior and cracking characteristics of early-age concrete. For the efficient numerical solution of multiphysics coupling problems, a fully implicit solution scheme was established. The governing equations for the hydration degree field, temperature field, moisture field, and mechanical field were all discretized using the backward difference scheme and solved implicitly through the assembly of the global stiffness matrix. This solution framework ensures numerical stability throughout the coupled computation process and achieves high-precision simulation of concrete shrinkage deformation and crack propagation. Numerical examples demonstrate that the proposed model effectively captures the stress distribution characteristics, crack initiation locations, and propagation paths of early-age concrete during the hydration heat generation, cooling, and moisture evaporation stages, providing a theoretical foundation and numerical tool for predicting early cracking risks in concrete structures and optimizing curing strategies.
Keyword: Concrete; Early-age cracking; Multi-field; Peridynamics; Mechanism analysis
河海大学研一级学生,方向为近场动力学理论以及多场耦合分析,现开展“早龄期混凝土化-热-水-力多场耦合开裂分析”。