在大体积混凝土结构中，约束区温度应力的控制具有重要意义。选择合适的浇筑层厚度是工程规划和制定温控方案的重要环节。通过对现阶段大体积混凝土温控措施进行总结，介绍考虑水管冷却的等效热传导方程，然后建立有限元模型分析不同层厚方案下约束区大体积混凝土的温控效果。结果显示：在算例给定条件下，层厚3．0 m 方案的温度应力最大值略小于层厚1．5 m 、2．0 m 方案，但对应混凝土龄期小于后两种方案。建议厚层浇筑时应优化二期冷却方案，以防止内部过早出现较大拉应力。%In massive concrete structures ,the thermal stress control in restraint area is of great significance .A proper concrete lift thickness is an important part of the whole project plan including the temperature control scheme .Here ,the temperature control measures of the mass concrete at the present stage are summarized ,and the equivalent equation of the heat conduction with cooling pipe is introduced ,then a FEM model is created to analyze the temperature control effect of the mass concrete in restraint area under different concrete lift thickness .The calculation results show that under the giv-en conditions ,the maximum temperature stress of 3 .0 m thickness is slightly less than the two others (1 .5 m and 2 .0 m thickness) ,while the peak value comes earlier than the two others .Thereby ,it is suggested that the second-stage cooling plan should be optimized when the thick concrete pouring to prevent the large internal temperature stress in earlier time .
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