山区桥梁超高墩日照温度效应数值分析

Numerical Analysis of Sunshine Temperature Effect on Super High Pier of Mountain Bridge

随着高速公路以及铁路建设的迅速发展,高墩凭借其诸多优点在深山峡谷的大跨度桥梁中大量被运用,然而高墩对外界环境温度变化敏感,由温差产生的应力及变形往往不容忽视。本文基于新庄特大桥工程实例,进行高墩的日照温度场及温度效应分析。依照太阳辐射理论计算出高墩外界气温和内腔气温,再转换成综合气温作为热边界条件作用在高墩模型上,随后进行高墩温度场的计算,将温度场结果作为荷载施加在有限元模型上,提取计算结果进行位移时程分析,找出大桥高墩温度效应的最不利情况作为控制指标。研究工作将对类似实际工程有一定的指导意义。

With the rapid development of the construction of expressways and railways,the high pier is widely used in large span bridges in deep mountains and gorges for its several advantages. However, the high pier is sensitive to the change of ambient temperature and the stress and deformation caused by the temperature difference cannot be neglected. Based on the construction of Xinzhuang Bridge, the temperature field and temperature effect of high piers are analyzed. According to the theory of solar radiation, the external temperature and cavity temperature of high piers are calculated and then converted into integrated temperature as a thermal boundary condition applied to the high pier model. Then the high piers’ temperature field is calculated and the temperature field results are applied to the finite element model as a load. The calculation results are extracted for the analysis of maximum displacement time history to find the most unfavourable temperature effect of the bridge as a control index. The research will play a guiding role in similar engineering practices.