A review on the deterioration of mechanical and durability performance of marine-concrete under the scouring action

Scouring action is recognized as one of the primary causes of the degradation of marine concrete in tidal and splash zones. It is not ignored that the deterioration of marine concrete is caused by the coupled effects of scouring action and chemical actions (e.g., Cl− attack, SO42- attack, carbonization, and alkali-aggregate reaction) and physical actions (e.g., salt crystallization, dry-wet cycles, freeze-thaw cycles, and external loading). This paper reviewed the deterioration mechanism of marine concrete under the combined impacts of scouring and other marine-environment multi-factors. The chemical action had both positive and negative impacts on marine concrete when subjected to scouring. The physical action exacerbated scouring and erosion damage to the marine concrete, and both interact with each other. In addition, the physical and mechanical performance of marine concrete under scouring action was investigated and analyzed, as well as deterioration indexes of marine concrete under multi-factors coupled action. The type and concentration of chemical solution, temperature, flow rate, and load-stress ratio were related to mechanical performances of marine concrete. The addition of nanoparticles and fibers, the application of admixtures, and other improvement methods to mitigate the durability deterioration of marine concrete were generally summarized.