| With the extensive application of massive concrete in civil engineering project the engineers pay increasing attention to temperature cracks. The key to control temperature cracks effectively lies in the precise prediction of temperature field and stress field. This dissertation employed finite element method to simulate the transient temperature field and stress field in massive concrete.A new formula was proposed to simulate the hydration heat of cement in concrete. The model takes the influence of temperature and concentration of reactant into account .The test showed that: this model can exactly simulate the heat release procedure during hydrated reaction of cement in massive concrete. The parameters in the model can be attained easily, and it's convenient to be applied in engineering.A finite element program, using 4~8 nodes two-dimensional isoparametric element and 8~20 nodes three-dimensional isoparametric element, was designed to apply the model to the finite element analysis of transient temperature field in massive concrete. Considering the elastic modulus of concrete varying with age, a program, using 4~8 nodes two-dimensional isoparametric element and 8~20 nodes three-dimensional isoparametric element was developed to analyze the thermal stresses. Influencing factor of temperature filed and stress filed in massive concrete was analyzed. Aimed at the concreting in lifts, a construction method that can reduce the temperature difference between the interior and the surface, the finite element program simulates the transient temperature field in massive concrete constructed layer by layer by controlling the contribution of each element to global stiffness matrix and load vector.Finally, applied the finite element program to the analysis of the temperature field and stress field of the massive concrete foundation in the main building of TongBo pumped-storage power station in Zhejiang province, and compared the result with field monitoring data.
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