新疆某混凝土重力坝运行期温度场和应力场反馈分析

Feedback research on temperature and stress field of concrete gravity dam in Xinjiang during operation period

新疆某混凝土重力坝自2007年开工以后,主河床坝段布置了温度计对大坝进行温度场的现场观测,至2012年积累了5年的温度观测资料。本研究依据已取得的现场温度观测资料,通过三维有限元反馈仿真分析,进一步校准仿真计算的边界条件和有关参数,达到提高大坝温度场和应力场预测精度的目的。研究表明仿真计算采用的方法是正确的,计算参数及边界条件也基本符合大坝的实际情况,完全可以满足大坝后期温度场及应力场预测的要求。大坝应力场计算结果显示,大坝在运行阶段受环境因素等影响,局部区域施加的温控措施的效果有所减弱,导致这些区域出现应力超标的现象,建议采取相关措施进行预防和处理。

Since the construction of a concrete gravity dam in Xinjiang in 2007,its temperature observa-tion data had been collected for five years from the thermometers buried in the dam till 2012.The paper used the temperature observation data to calibrate the boundary condition and the calculating parameters by 3-D FEM feedback analysis to improve the prediction accuracy of the temperature and stress of the dam.The analysis indicates that the boundary condition and the calculating parameters adopted were consistent with the actual condition of the dam which can be used to predict the future temperature and stress of the dam.The calculating results show that the tensile stresses in partial areas of the dam exceed the allowable value because of the weakened effect of temperature control measures influenced by the changing environ-ment during the operation period of the dam.It is suggested that some protective treatment be taken in these areas.