不同种类硫酸盐溶液侵蚀下混凝土损伤研究

研究了混凝土在不同种类硫酸盐溶液与干湿循环作用下的损伤层厚度演化规律，分析了损伤层混凝土的力学性能，得到了损伤层混凝土抗压强度。研究结果表明：随着侵蚀时间增加，混凝土损伤层中超声声速降低，损伤层厚度增大，并且损伤层混凝土抗压强度明显降低。当混凝土损伤层越厚、声速越低时，其损伤程度越大。混凝土在硫酸镁溶液中的损伤层厚度最大，且抗压强度劣化明显，混凝土侵蚀破坏最严重；硫酸钠与氯化钠的复合溶液中混凝土损伤层厚度最小，其抗压强度降低最少，氯离子的存在降低了混凝土的损伤劣化程度。

Damage of Concrete under Sulfate Attack Exposed to Different Types of Sulfate Solution

The degradation rule of concrete damage layer subjected to drying-wetting cycles in different types of sulfate solution was studied in the paper. Moreover, the mechanical properties of the damage layer was analyzed. Then the compressive strength of concrete in damage layer was obtained. The experimental results showed that the ultrasonic velocity in the damage layer decreased and the surface damage layer thickness of concrete increased with corrosion time, and the compressive strength in damage layer reduced obviously. When the damage layer thickness of concrete is thicker and the ultrasonic speed is lower, indicating that the deterioration degree of concrete increases. The concrete deterioration by magnesium sulfate covers the most aggressive corrosion, the damage layer thickness of concrete is the largest, and its compressive strength reduces obviously. The damage layer thickness of concrete in composite solution of Na2 SO4 and NaCl is the least, and the decrease of compressive strength is the lowest. The presence of chloride ions reduces the degradation degree of concrete under sulfate attack.