Different Salt Solution on the Deterioration of Marine Engineering Concrete under the Action of Chemical-Mechanical Coupling

Abstract

The loaded specimens were put in fresh water, 3.5%NaCl solution, 5.0%Na2SO4 solution, and simulated sea water with different concentrations respectively, and then the damage process under wetting and drying cycle was investigated. The ultrasonic non-metal testing technology, X-CT scanned image, free chloride and sulfate ions chemical titration were used to investigate the degradation of the marine concrete under the coupling effect of Chemistry and Mechanics. The effect of solutions, wetting and drying cycle and bending stress to the durability of marine concrete were further studied. The results indicate that different salt solution affects marine concrete at different degrees: sulfate salt is more corrosive than chloride salt, simulated seawater is similar to 5.0%Na2SO4 solution, while five-time simulated seawater is the most corrosive; wetting and drying cycle remarkably accelerates the penetration of corrosive ions, which results in the concrete damage, compared to the corrosive environment, concrete is damaged violently under the coupling effect of Chemistry-Mechanics and tensile stress has greater influence on the damage.