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In large concrete structures , the temperature change has an important impact on the stress state of the structure . Sometimes the temperature stress may exceed the stress caused by other external loads , and grasp the variation of temperature stress for reasonable structural design is extremely important . Temperature stress is one of the main factors of mass concrete cracks damage due to the large volume of concrete material properties and work environment , and thus analysis of mass concrete temperature field and thermal stress field is essential . The temperature field and thermal stress problem of large concrete structures is the main object of study in engineering stress analysis of hydraulic structures . As the main building of the Dam , Spillway Chamber of part of the temperature and stress field there are many issues to be further research and analysis . Due to the special role of the gate chamber , the surface of the overflow weir and the concrete pier numeral higher , combined with a large volume , the concrete in the process of the curing , due to the hydration of the action of heat , resulting in higher internal temperature of the chamber gate concrete , plus strong binding effect on the bedrock , may have a greater thermal stress cracks in the concrete surface when its value reaches a certain level , it will , and even the deep cracks and through cracks appear , therefore , to take a certain temperature control measures , the lock chamber concrete temperature field and thermal stress simulation , it is very necessary to prevent and reduce the occurrence of cracks . Papers according to the heat conduction theory , three-dimensional finite element theory , the three-dimensional temperature field finite element calculation formula is derived ; thermodynamic basic theory , three-dimensional finite element theory and concrete Xu variable theory , three-dimensional temperature Xu variable stress field of finite element calculation formulas are derived ; according to the actual situation developed three temperature control options in the surrounding rock in consideration of the initial temperature field , the concrete stratification pouring concrete hydration heat volume deformation and creep on the basis of self-generated , the preparation of the temperature field and thermal stress calculation program powerful computing capabilities , make full use of the computational analysis software ANSYS to simulate the actual construction process , construction and operation period of the lock chamber concrete calculated temperature field and temperature stress , and analyze the different thermostat program lock chamber temperature stress, provide the basis for the actual construction .
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