酸雨作用下钢纤维煤矸石混凝土耐久性研究

摘要

In order to study change characteristics of durability indexes of steel ifber reinforced coal gangue concrete under different pH values of acid rain solution and steel ifber content, which including mass, splitting tensile strength and carbonation depth, based on the cyclic corrosion test of acid rain. The test result shows that in the pH=2.0 acid rain solutions, steel ifber reinforced coal gangue concrete reaches its maximum mass at the ifrst cycle of acid rain, and the mass increase rate of steel ifber reinforced coal gangue concrete is 0.25%, then drops to the minimum mass and gets its the peak of mass loss rate when the value is 2.37%. In pH=2.0 acid rain solution, the loss rate of splitting tensile strength is approximate linear increasing with the cycle number, the peak loss rate is 21.91%. The relationship between carbonation depth and cycle number of acid rain is positive in the different pH values of acid rain solution, and the signiifcant strength is pH=2.0>pH=3.0>pH=4.0. The optimal steel ifber content of steel ifber gangue concrete is 1%, and optimizes its air space structure then effectively inhibits the erosion of acid rain.%基于酸雨循环侵蚀试验，探究了在不同pH值酸雨溶液与钢纤维掺量条件下，钢纤维增强煤矸石混凝土质量、劈裂抗拉强度及碳化深度等耐久性指标的变化特性。结果表明：第1次酸雨循环时，pH值为2.0酸雨溶液中钢纤维煤矸石混凝土达到最大质量，其增加率为0.25%，随后骤降到最小质量，其质量损失率峰值2.37%；钢纤维煤矸石混凝土劈裂抗拉强度损失率与循环数呈近似线性关系，其最大损失率为21.91%；不同pH值酸溶液中钢纤维煤矸石混凝土碳化深度与酸雨循环数呈正相关，显著性表现为pH=2.0＞pH=3.0＞pH=4.0；1.0%钢纤维掺量是钢纤维煤矸石混凝土的最优掺量，可优化其空隙结构，有效抑制酸雨溶液的侵蚀。