空心高桥墩日照时变温度场及温度效应研究

Study on Sunshine Time-dependent Temperature Field and Temperature Effect of High Hollow Piers

为了深入揭示空心高桥墩在日照温度作用下的温度场分布规律及温度效应,以衢宁铁路某大桥混凝土桥墩为工程背景,进行空心高桥墩温度场的观测试验。在实测温度场数据的基础上,根据太阳物理学及传热学相关理论,考虑太阳辐射、长波辐射、对流换热、风速等因素,建立桥墩三维瞬态日照温度场有限元数值仿真模型,有限元分析结果与实测数据对比表明两者吻合较好,反映出温度场有限元数值分析的准确性和实用性;在有限元分析的基础上,进一步采用最小二乘法拟合出适合该桥的空心高墩沿壁厚方向的梯度模式,并与规范对比;最后,通过热一结构耦合分析,得到空心高墩在日照温度作用下的应力分布。

In order to study the distribution of temperature field and temperature effect of high hollow piers under solar radiation, the temperature field of one high hollow concrete bridge pier on Quzhou-Ningde Railway was observed and measured.Based on solar physics and the theory of heat transformation, a three-dimensional finite element model of the high hollow concrete pier is built using the measured data.The model considers solar radiation, long wave radiation, convection heat transfer, wind speed and other environmental effects.The comparisons between the results from finite element analysis and the measured data show a good agreement, indicating the accuracy and practicality of the finite element model.Accordingly, the temperature gradient mode of the high hollow concrete pier along the radius direction is fitted using the least square method.Finally, the temperature stress field of the high hollow concrete pier under solar radiation is obtained from the thermal structure coupling analysis.