不同粗细骨料组合下的混凝土耐硫酸腐蚀研究

Research on Concrete Sulfuric Acid Resistance with Different Types of Coarse and Fine Aggregates

为比较不同粗细骨料组合对混凝土耐硫酸腐蚀性能的影响,对水灰比为0.45、尺寸为100×200的4种骨料组合(青石+黄砂,青石+大理砂,大理石+黄砂,大理石+大理砂)混凝土试件进行耐硫酸加速腐蚀试验。将混凝土试件浸泡于pH值为0.95左右的硫酸溶液中进行为期194d的12次跟踪监测,根据检测数据计算得到了混凝土的腐蚀深度,按线性方程斜率从大到小对4种骨料组合混凝土硫酸腐蚀速率进行了排序。结果表明:含有大理石或大理砂骨料的混凝土比含青石和黄砂骨料的混凝土耐硫酸腐蚀性能高;腐蚀层受扰动情况下,腐蚀深度与腐蚀时间呈线性关系;大理石细骨料比大理石粗骨料更有利于减小腐蚀深度。

In order to compare the impact of fine and coarse aggregates on concrete sulfuric acid resistance, accelerated corrosion experiment was conducted with four types of aggregate concretes composed of coarse and fine aggregates （gravel and river sand, gravel and marble sand, marble stone and river sand, marble stone and marble sand） and same water cement ratio of 0.45 and Ф100× 200. The concrete specimens were kept in sulfuric acid solution with pH value range around 0. 95, and 12 times continuous monitoring tests were carried in 194 d. The corrosion depth was calculated based on the monitoring data. The corrosion rates of the four types of concretes were sorted in descending by the slope. The results show that concrete with marble aggregates rich in calcium carbonate has better performance in sulfuric acid solution than that with inert aggregates （gravel and river sand）. Corrosion depth is linear with corrosion time when concrete sulfuric acid corrosion layer is interrupted. Moreover, the marble fine aggregate plays more important role on reducing concrete sulfuric acid corrosion depth than marble coarse aggre- gate.