应力水平对矿物掺合料混凝土氯离子渗透性的影响

Effect of stress level on chloride ion permeability of mineral admixture concrete

矿物掺合料混凝土作为一种高性能混凝土,逐渐成为恶劣环境下钢筋混凝土结构的首选材料,其耐久性能对整个结构的使用寿命至关重要。考虑服役于近海、盐碱、除冰盐环境下的桥梁结构,遭受氯离子侵蚀和循环荷载的共同作用,开展了不同应力水平下矿物掺合料混凝土氯离子渗透性的试验研究。研究结果表明:应力水平越大,混凝土渗透性越好,氯离子更易侵入;侵蚀深度增加,氯离子浓度减小、扩散系数增大;侵蚀时间增长,氯离子浓度增加、扩散系数降低。

Mineral admixture concrete regarded as a kind of high performance concrete,has been a preferred material of reinforced concrete structure under the harsh environment, and its durability is critical to the life of the whole structure.Bridge structure serving in the offshore, saline, deicing salt environments, subjected to chloride ion erosion and cyclic loading was considered, and the experiments study of chloride ion penetration of mineral admixtures concrete under the different stress level were carried out.The results show that the greater the stress level, the better the permeability of concrete, and the more easily the chloride ion.The chloride ion concentration decreases with the erosion depth increasing,while the diffusion coefficient increases.The chloride ion concentration increases with the erosion time increasing, while the diffusion coefficient decreases.