| The phenomena that occur during early stages of concrete are very complicated, as chemical-thermal-hydration and mechanical effects must be solved. Furthermore, in reality, multi-layered concrete structures are extensively used, the interface exists in this complicated situation, causing the modeling of early-age concrete to become an even more difficult task from the standpoint of numerical analysis. Although some pioneering work has already been made separately in the concrete nonlinear analysis and the early-age concrete property investigation, the combining of the fundamental understanding of early-age concrete properties into a practical numerical modeling program remains to be developed.; In this study, the early-age concrete properties, including hydration, creep, stiffness development, heat conduction, ambient temperature and wind speed effect, and others, are fully simulated in a developed brittle elastic model. Furthermore, a simplified model is also developed to allow for quantitative simulation of crack-induced damage. A general purpose elastoplastic model is developed to accommodate the interface problem, considering a coupled elastoplastic creep model for nonlinear failure problem related to the cementitious interface materials. Throughout this study, the efficiency of the iterative algorithms is improved by the proposed novel solution algorithms for solving the nonlinear equations. |
