Analysis of Expansion Stress Evolution of Concrete Erosion Products for Ocean Engineering

Abstract

AbstractWith the deployment of China's “Maritime Power” strategy and the continuous development of ocean engineering, the safety and sustainability of concrete materials in ocean engineering need to be resolved urgently. In this paper, aiming at the concrete erosion caused by sulfate in marine environment, the evolution analysis of the expansion stress of the erosion products is carried out based on the principles of thermodynamics and crystallography. The results show that there is a liquid film between the ettringite and the pore wall during sulfate erosion in marine environment. The interfacial energy between reactants of different phases should not be neglected, and the liquid film thickness is negatively correlated with the expansion stress. The radial stress on concrete microstructure is composed of expansion stress, seawater pressure and interfacial energy between the concrete pore wall and the seawater. The trends of radial stresses in micro-voids and micro-cracks are basically similarly, both of which are negatively correlated with pore size and positively correlated with erosion time. In addition, the radial stresses in micro-cracks are generally greater than those in micro-voids. During the erosion process, the radial stress is positively correlated with the expansion extend of ettringite.