Study on the Durability of Normal Strength Concrete under the Action of Salt Corrosion and Dry-Wet Cycles

Abstract

The degree of soil salinization in the west region of Jilin province is very serious, where the composition of salts in the soil and surface water is complex and mainly contains Na+, HCO3- or CO32-, Cl-, SO42-, etc. The concrete engineering projects in such environments are often corroded by a variety of salt corrosion damage under the condition of dry-wet alternation. Based on the previous experimental study on the durability of concrete affected by the factors of both multiple salts and dry-wet cycles, different salts (bicarbonate, sulfate, and chloride salt) soak and dry-wet cycle tests to normal strength concrete (NSC) are conducted in this article. The test results show that all of the bicarbonate, sulfate, and chlorine salt can cause certain corrosion on NSC under the condition of dry-wet cycle. The influence degree of different harmful salts on the mass loss of concrete is as NaHCO3 > Na2SO4 > NaCl > water; the influence degree of different salts on the dynamic elastic modulus of concrete is as NaHCO3 > Na2SO4 > NaCl > water. Under the condition of dry-wet cycle, a variety of salts can make the erosion damage of concrete produce superposition effect, and make the concrete corrosion damage sharpened.