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在水利工程中采用浇制混凝土的方法修建高坝,由于混凝土中的水泥在水化过程中发出大量的热量,当热量与外界温度形成过大的温度差时,则产生裂缝,从而破坏了混凝土的整体性。为了防止这种裂缝的产生,施工中除需要采取人工冷却、降温、散热等措施外,还必须采用分块分层浇制,而两层之间又需要5～10天或更多的间歇时间,才能保证浇制的混凝土不产生裂缝,这样就严重地影响了施工速度,同时由于水电站多修建在峡谷地区,施工场地一般较为窄狭,材料运输及混凝土浇注都受到一定限制,即使以高度机械化施工,亦不可能高速度的前进。由于施工速度受到限制,在短时间内不可能将主要工程一气呵成,为了防御洪水对施工的威胁,施工导流工程就不得不修建的比较坚固可靠,因而也就大大的增加了施工导流的困难与费用,这种情况对长江三峡水利枢纽来说,尤为严
In the water conservancy project using the method of pouring concrete to build high dam, concrete in the cement hydration process emits a lot of heat, when the heat and the outside temperature to form an excessive temperature difference, then cracks, thus undermining the concrete The integrity of. In order to prevent the occurrence of such cracks, in addition to the need to take artificial cooling, cooling, cooling and other measures in the construction, but also must be divided into separate layers of pouring, and between the two layers and 5 to 10 days or more intermittent time , In order to ensure that the pouring of concrete does not produce cracks, thus seriously affecting the construction speed, and more hydropower stations built in the gorge area, the construction site is generally narrow, material transport and concrete pouring are subject to certain restrictions, even with a high degree of mechanization Construction, it is impossible to advance at high speed. Due to the limited construction speed, it is impossible for the major projects to be done in one go in a short time. In order to prevent the threat of flood to the construction, the construction diversion project has to be built more solidly and reliably, thus greatly increasing the difficulty of construction diversion And the cost, this situation is particularly severe for the Three Gorges Project