混凝土坝表层碳化及其危害性分析

随着时间的推移，混凝土坝表层碳化现象日益加重。许多工程实践表明，采用劣质材料和较差的混凝土配合比，施工质量差，未进行表面养护，以及环境相对湿度较小时，混凝土碳化速度较快；有的坝在混凝土龄期30年以后碳化趋势尚未收敛稳定。混凝土坝的梁、柱构件因碳化引起钢筋锈蚀膨胀，产生顺筋裂缝和混凝土崩落的现象比较普遍。轻型平板坝因碳化严重．使面板挡水功能受到危害的问题．应引起高度重视．并应及时进行处理。

Surface carbonating of concrete dam and its perniciousness analysis

Surface carbonating problem of concrete dams is getting more and more serious with time. Many project practices have proved that it is of faster speed in concrete carbonating because of poor cement used, more water contained, no water-reducing agent and air-entraining agent added, poor construction quality without surface protection, as well as relative lower environmental humidity. Even more the carbonating trend is still forwarding for some dams with the age over 30 years.The reinforcement of the beam and coulmn members of some concrete dams have been rusted and expanded due to carbonating. Thus, it is general that the concrete is cracking along reinforcement and then collapsing. High attention should be paid to and the concrete should be treated timely for the damaged slab so as to retain their function due to the serious carbonating of light flat slab dam.