关键词: 喷射混凝土;复合盐;共同作用;离子分布规律;氯离子扩散系数

Abstract: The pore solution of pH value, Cl-, SO2-4 and Ca2+ distribution situation of ordinary concrete, ordinary shotcrete and steel fiber shotcrete are analyzed under the combined action of (wetting and drying cycles + compound salt erosion), the ions distribution regularity and chloride ion diffusion coefficient of shotcrete are investigated.The results show that the pH value and Ca2+ concentration distribution regularity with depth of each concretes are similar, and all lowest on surface, increase with depth increasing, and decrease with the age increasing in the same depth.The Cl-concentration of ordinary concrete surface is the highest, and its diffusion depth is the lowest, but steel fiber shotcrete contrasting with ordinary concrete.The distribution of SO2-4 in the concrete can be divided into three segments, rich region, transition region and stable region.The Cs of ordinary concrete > ordinary shotcrete > steel fiber shotcrete, and increase gradually with the age increasing.The D reduced gradually with the age increasing, which is in accordance with the law of the variation of power function.

Key words: shotcrete;compound salt;combined action;ions distribution regularity;chloride diffusion coefficient