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通过对国内15座混凝土大坝裂缝的调查分析及仿真反馈计算归纳总结出了混凝土裂缝的原因，探索了混凝土防裂的途径和措施．提出混凝土热膨胀系数直接影响温度收缩应力，决定热膨胀系数大小的是骨料的岩性，选用热膨胀系数小的骨料有利于降低混凝土内部产生的温度应力．由外部环境造成裂缝危害的主要原因是寒潮袭击，其防范措施为采用“薄层、短间隙、均匀上升”的浇筑方式和妥善的表面防护．其它骤然降温因素毛不容忽视，如遭遇洪水浸泡、冷却管内冷却水与混凝土内部温差过大等．此外，结构设计、分缝分块和施工工艺也要给予充分重视．
Through the investigation and analysis of the cracks in 15 concrete dams in China and the simulation feedback calculation, the causes of the concrete cracks are summarized and the ways and measures of concrete crack prevention are explored. It is put forward that the coefficient of thermal expansion of concrete directly affects the temperature shrinkage stress and the coefficient of thermal expansion determines the lithology of the aggregate. Selecting the aggregate with small coefficient of thermal expansion is helpful to reduce the temperature stress generated inside the concrete. Cracks caused by the external environment, the main reason for the cold wave attacks, the preventive measures for the use of “thin, short gap, uniform rise” pouring and proper surface protection. Other sudden cooling factors hair can not be ignored, such as flooding encountered in the cooling pipe cooling water and concrete temperature difference is too large. In addition, structural design, sub-block and construction process should also give full attention.