受侵蚀混凝土耐久性能下降影响因素试验研究

Experimental study on the factors affecting the durability of corroded concrete

为提高混凝土面临复杂环境,尤其在硫酸盐环境中的耐久性,在特定的硫酸盐环境下,对市场上的不同水胶比混凝土进行研究测试。通过分析不同水胶比、硫酸盐浓度以及处理时间,详细分析导致混凝土耐久性变差的因素,并对轴心抗压强度、动弹性模量、氯离子扩散系数等指标进行研究。试验结果表明:混凝土中水胶比对其理化性能存在巨大的影响,较小的水胶比有利于提高混凝土的耐久性;在研究设置的硫酸盐浓度范围内(0~15000 mg/L),随着离子浓度增加,混凝土各性能指标如劈裂强度氯离子渗透系数等呈现出先增大后减小的趋势,并且此类指标均对浓度变化较为敏感。

In order to improve the durability of concrete facing complex environment in China,especially in sulfate environment,it takes the basic material of power tower in a certain area as the research object,and carries out research and test on concrete with different water-binder ratio in the market under specific sulfate environment.Through the analysis of different water-binder ratio,sulfate concentration and treatment time,the factors leading to the deterioration of concrete durability were analyzed in detail,and the indexes such as axial compressive strength,dynamic elastic modulus and chloride ion diffusion coefficient were studied by national standards.The experimental results show that the water-binder ratio in concrete has a great influence on its physical and chemical properties.Within the range of sulfate concentration set in the study(0~15000 mg/L),with the increase of ion concentration,concrete performance indexes,such as chloride ion permeability coefficient of splitting strength,showed a trend of first increasing and then decreasing,and these indexes were sensitive to concentration changes.