MICRO-PHYSICAL APPROACH TO COUPLED AUTOGENOUS AND DRYING SHRINKAGE OF CONCRETE

摘要

The proposed autogenous and drying shrinkage model is derived from micro-mechanical physics of water in pore structure in concrete. In the modeling, the shrinkage of concrete due to self-desiccation, known as autogenous shrinkage, is idealized to be driven by the surface tension force of capillary water across curved meniscus, similar to drying shrinkage processes. The overall material properties of concrete are evaluated considering the inter-relationship of hydration, moisture transport and pore-structure development processes based upon fundamental thermo-physical models. By implementing the shrinkage model to this system, the volumetric change of concrete can be predicted for different water to cement ratio, curing and mix proportions satisfactorily.