衬砌混凝土裂缝的预防和修补方法

Prevention and Repairing Measures for Cracks in Lining Concrete

输水渠道是引水式电站的主要组成部分。南水北调渠道衬砌裂缝主要为应力裂缝和沉陷裂缝,两类裂缝的产生主要是养护、切缝不及时和垫层、管沟、渠基压实度不足造成的。通过控制混凝土配合比、渠基与填筑料压实质量、调整施工工序等,有效预防了裂缝的产生。对衬砌裂缝采用双组份聚硫密封胶进行修补,施工工艺简单,耐久性好,且无毒无污染,修补效果良好。

Water conveyance channel is the main component of the diversion type power station. In the water conveyance channel of the South-to-north Water Diversion Project, stress and settlement cracks are observed in the concrete lining. Analysis shows that these cracks are caused either by the untimely curing and cutting of the concrete lining or the insufficient compacting of the cushion, pipeline trench and foundation. Therefore, with the control of the concrete proportion, compacting quality improvement of the trench foundation and filling materials, and adjustment of the construction processes, the cracks could be effectively prevented. For the repairing of the existing cracks, the two - component polysulfide sealant is adopted, which is non-toxic, pollution-free, easy for construction, durable and also of satisfactory repairing performance.