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中文摘要：
针对大体积混凝土锚碇施工期温度控制比较困难的问题，基于瞬态温度场和温度应力场有限元仿真计算理论，依托非线性有限元程序ANSYS，从某大桥大体积混凝土锚碇分层浇筑动态施工过程的实际环境出发，对其施工期和运行期的温度应力进行仿真计算，分析锚碇的温度应力特征。计算中考虑外界气温的周期变化、太阳辐射、水化生热、浇筑温度、分层厚度、边界条件变化、分层浇筑动态施工过程及混凝土徐变和弹性模量变化等因素。计算结果给出了大体积混凝土锚碇特征点温度应力变化曲线以及温度应力场的分布和变化规律等。研究结果表明：施工期，节点温度应力呈压应力升高和降低相互交替出现态势，基础约束范围内的边缘点会出现拉应力，施工结束后，节点温度应力进入呈简谐变化状态，且变化幅值外部大于内部，此后，随着水化热的逐渐散失，加之混凝土徐变的影响，最大温度应力逐渐减小；锚碇内部一般表现为压应力，表面拉应力值相对较大，而早期混凝土抗拉强度小，故锚碇外侧表面有可能出现早期表面裂缝；锚碇顶部混凝土体积相对较小，受环境温度的影响，其侧表面拉应力值相对较大，但未超过抗拉强度；建基面以上基础约束范围内及每一间歇层面，都会出现了拉应力，在设计和施工过程中应值得注意。
英文摘要：
Associated with dynamic state process of constructing in layers of the physical engineering circumstance of massive concrete in anchor - mound of some bridge and based on the transient heat three - dimensional finite - element method, temperature field during the course of construction and operation of massive concrete was simulated on ANSYS software consideing factors of periodic variation of atmospheric temperature, solar radiation, heat of hydration of cement, concrete constructing temperature, layer thickness, variation of boundary conditions with time, dynamic state process of constructing in layers. Curves of time -temperature of characteristic points and characters, space -time distribution, regularities of change of massive anchor- mound constructed in layers were supplied by emulation and analysis. Analyzed results show： the changing course of temperature of point in massive concrete of anchor -mound obeys the general regularity;the key influencing factor of the temperature in concrete of anchor -mound during the course of construction is heat of hydration of cement, but in operational time the atmospheric temperature is a decisive factor;heat of hydration of cement is the uhimatest and directest factor which affects temperature rise, the substantive measurement that reduces temperature rise is to use low - heat cement and reduce the amount of cement;the temperature gradient is great relatively near the exterior of surface and it is small inner in temperature field of massive concrete, so cooling inner, thermal retardation exterior and maintenance of concrete should be pay attention to in early time.
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