Freeze-thaw damage mechanism and multifield coupling simulation analysis of port hydraulic concrete buildings

This paper takes the concrete structure berth wharf of Tianjin Port as the research object, conducts on-site investigation on the status of freeze-thaw of the port's concrete structure, determines the distribution law and the most unfavorable position of the freeze-thaw damage of the port's hydraulic concrete building components, and based on the osmotic pressure theory analyzes the concrete freeze-thaw damage mechanism and calculation of average pore pressure during concrete freeze - thaw process. Considering the coupling effect of temperature field, seepage field and stress field, the failure process of concrete under freeze-thaw cycles was simulated by Comsol Multiphysics, and the distribution characteristics and variation laws of temperature field, seepage field and stress field were obtained. The research shows that the freeze-thaw damage of concrete components in Tianjin Port Wharf shows obvious regularity, and the freezing of internal pore water is the direct cause of freeze-thaw damage of concrete structures. The average p process of concrete is closely related to the freeze-thaw temperature and the number of freeze-thaw cycles. During the freezing and thawing process of the concrete specimen, the temperature of the specimen gradually decreased from the surface to the center, and the seepage velocity inside the specimen showed the law of Z direction>Y direction>X direction. and the distribution characteristics of stress and strain were consistent, and both showed big peripheral, the center is small and relatively symmetrical. The rese arch results can provide a theoretical reference for the safe operation and maintenance of port hydraulic concrete structures.