南水北调东线睢宁二站流道混凝土温控防裂措施

水工混凝土裂缝问题是涉及工程安全、质量的首要问题。新建睢宁二站工程,总结了已建工程实施的经验,并针对已建及周边在建泵站工程有裂缝出现的情况,分析原因,结合睢宁二站工程地质、气象条件、以及工程所在地施工特点,进行温控设计。针对温控对象中的重点——流道部分,根据睢宁二站底板大体积混凝土浇筑实施效果和成功经验,在选择原材料、施工工艺等方面,对混凝土温控防裂措施加以优化。从实施效果的各项指标统计和分析表明,优化措施达到了预期成效。尤其流道部位混凝土,至今仍未发现危害性裂缝。

Temperature Control and Crack Prevention Measures of the Concrete in the Flow Channel of Suining No.2 Station in the Eastern Route of the South-to-North Water Transfers Project

The cracks in the concrete for hydraulic structure are the primary issue in the safety and quality of the engineering projects.The new Suining No.2 station was constructed in light of the experience of previously constructed projects.The reasons for the occurrence of the cracks in the pumping station projects which were constructed or under construction were analyzed.Considered the engineering geology,weather conditions,and construction features in the Suining No.2 station,the temperature control was performed.The flow channel,the most important aspect of temperature control,was focused.Based on the analysis of the implementation results and successful experience of mass concrete casting in the bottom of Suining No.2 station,the temperature control and crack prevention measures were optimized from the aspects of raw materials and construction technology.The statistics of each index showed that the implementation results reach the expected performance,especially no cracks were found at the concrete in the flow channel.