隔河岩大坝深表孔混凝土裂缝成因分析与处理

Analysis and Treatment of Concrete Cracks in Overflow and Deep Spillways in Geheyan Dam

隔河岩水电站经过27年的运行,泄洪孔底板、边墙混凝土裂缝逐渐发育,2014年专项检查累计长度已近2 600 m,裂缝对过流面和大坝结构均产生危害。对裂缝的成因分析表明,部分裂缝为局部应力集中导致,浅表性裂缝多为温度应力造成,此外也与混凝土长时间干湿变化频繁等有关。为确保工程寿命与安全,对裂缝分别采用了环氧树脂系列化学材料进行处理。湿缝进行化学灌浆,浅表干缝进行表面涂刷养护,均取得了较好效果。

After 27 years of operation of Geheyan Hydropower Station,concrete cracks are gradually developed in the bottom plates and the side walls of the dam spillways.A special inspection in 2014 shows that the accumulated length of cracks is nearly 2600 m,which endanger the overflow surfaces and the dam structure.Analysis shows that part of the cracks are caused by local stress concentration,while most of the shallow cracks are caused by temperature stresses.Also,they are related to the long-time frequent drying and wetting changes.To ensure the life and safety of the project,the cracks are treated with epoxy resin type chemical materials.Chemical grouting is carried out for wet cracks,and surficial painting and curing are carried out for shallow dry cracks,both of which achieve satisfactory results.