渠道砼衬砌体裂缝的成因及预防

Causes of Cracks in Concrete-lined Channel and Its Prevention

在灌区节水项目建设中,渠道砼衬砌占有重要地位。砼的早期裂缝和运行过程的裂缝是常出现的问题,渠道砼裂缝成为影响工程质量乃至工程寿命的重要因素,笔者通过近年在宝鸡峡大小渠道处砼衬砌施工的实践,认为夯实好基础是保证砼不裂缝的前提,把好材料进料关是防止砼不裂缝的保证,正确选择好水灰比和骨料比及搅拌、振捣是砼衬砌的重要环节,原浆收面二次压光是减少蜂窝、麻面和早期裂缝的手段,科学合理的分缝是避免运行过程中防止裂缝的必要措施,抓好砼早期养护是提高砼质量避免裂缝的有力保障。

In water-saving irrigation projects, concrete-lined channel is of great importance. Cracks in concrete often occurs and it affects the engineering quality greatly, as well as the using life of the channel. With years of engineering practice, the author puts forward some effective measures for cracks in the concreted-lined channel, such as solid foundation, high-quality material, rational ratio of water and concrete, and aggregate rate, mixing, shaking and disturing of concrete, secondary pressing of concrete surface, and rational parting and early maintenance.