The 4th Asian Concrete Federation Symposium on Emerging Technologies for Structural Longevity (ACF2023- ETSL)

72 / 2022-04-12 16:59:52

Experiments and numerical simulations of water and ion transport in unsaturated cementitious materials

Load,Cementitious materials,Microstructure,Transport,Failure

The failure of concrete is actually a process of micro-scale cracks, which develops to macroscale

cracks. However, in the actual service state, cement-based materials generally work with

cracks. Different from the traditional experimental test, on the microscopic scale, limited by

the existing technical means, the damage research is more carried out by numerical simulation.

Based on the existing cement hydration model, the specific hydration microstructure is

obtained, and the damage analysis is carried out to obtain the hydration microstructure in the

damaged state. The results show that the damage process of microstructure of cement-based

materials is a process of damage accumulation, and the final failure is caused by a main crack;

In the process of damage, the change of crack connectivity and crack width will cause the

change of ion diffusion performance, and the change of diffusion performance can be divided

into four stages, and the crack threshold of diffusion performance change can be obtained.