多盐耦合腐蚀环境下混凝土性能劣化规律.

In order to explore the effect of the actual industrial chemical corrosion environment on the physical and mechanical properties of concretes, the site exposure tests of half immersion and full immersion were adopted in the chlorine, sulfate and magnesium salt environments, and therewith the corresponding corrosion simulation tests were carried out in the laboratory. The effects of different water-binder ratios, different corrosion concentrations and different dry-wet periods on concretes' quality, compressive strength, dynamic elastic modulus and thickness of the damaged layer were studied. The results showed that the relative mass, relative dynamic elastic modulus and compressive strength of half-immersed concretes and laboratory simulated concretes all increase first and then decrease with time and the thickness of the damaged layer continues to increase with time. The degradation damage of full-immersed concretes is much lower than those by half immersion, and the time required for each turning point by full immersion is prolonged. With the increase of the water-binder ratio, concentration, and shortening of the dry-wet period, it is easier to produce Friedel ' s salt, ettringite, and magnesium hydroxide in concretes, and accelerate the deterioration of concretes. The order of corrosive ions infiltrating into concretes is: chloride ions, sulfate ions and magnesium ions. [ABSTRACT FROM AUTHOR]