| Concentrated on the questions of temperature control and crack prevention studies on concrete of arch dams, simulative calculation theories of temperature and stress fields of mass concrete are systematically studied in theory and practice, the temperature control and the crack prevention methods of Zhougongzai arch dam in Ningbo is analyzed and studied in detail. The main contents are as follows:The development of the arch dams, the FEM methods of temperature field and stress field simulation and the back analysis of the mass concrete temperature field is overviewed.The simulation theories and methods of pipe-cooling temperature field and stress field is overviewed. Based on the proposed theories and methods, a 3-D simulation program concerning pipe-cooling mass concrete temperature field and stress field is designed and coded.The selection of concrete thermal parameters is key component in the concrete temperature filed simulation. Basing on the temperture data, the author use the 3-D FEM program for temperature simulation and the genetic algorithms to back analysis the concrete thermal parameters, good result is achieved.The cracks of arch dams are harmful to the safety and durability of concrete structures. To solve this problem, a series of methods for temperature control and crack prevention is presented based on studies of the cause of cracks.Based on above theories, the simultion and the practical application to Zhougongzhai arch dam in Ningbo Zhejiang are developed in details. The effect to the layout of the pipes,the methods of pipe-cooling, layer thickness of construct, day and night temperature ,cold wave,the methods of heat preservation to temperature field and stress field are studied in details,and the pertinent measures of temperature control and crack prevention are suggested, to settling the practice problems in projects. The application results show that the study achievements has excellent practicability and solve the pratical problems..
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