某重力坝温控仿真计算及上游面裂缝成因分析

某重力坝在设计施工中，采取了一系列严格的温控措施，但在施工中，上游面仍先后发现了各种类型的许多裂缝，其原因令人费解．作者收集了该坝的环境、施工、温控措施、材料等方面的详细信息，模拟该坝某坝段上游坝块的施工过程，对该坝块进行了细致的三维仿真计算，计算结果与该坝的裂缝分布吻合较好，因此，可以较好地解释该坝的裂缝原因．计算结果表明，虽然该坝的设计施工单位对温度控制相当重视，坝体分缝、施工进度、浇筑温度、水管冷却等措施基本得当，但由于对表面保温重视不够，措施不力，导致在昼夜温差、寒潮与气温年变化的综合影响下，在上游面出现大量水平与铅直裂缝．

Analysis of the cause for cracks on upstream surface of a gravity dam

Mang cracks were found on the upstream surface of a gravity dam in construction period although a series of temperature control measures were taken in the construction process of this dam, and the reason of cracking is unexplainable. The detailed information (such as environment, construction, temperature control measures and material properties) about the dam was collected, the temperature field and stress field of a monolith of the dam is calculated by simulating the construction process. The numerical result is in good agreement with the actual distribution of cracks on the upstream surface, therefore the cause for the cracks can be explained quite well. The numerical result shows that a lot of horizontal and vertical cracks on the upstream surface of the dam were caused by the action of the cold wave and the annual variation of air temperature, because no stric superficial thermal insulation were adopted despite some measures for controlling internal temperature were adopted.