南京大胜关长江大桥CPⅢ点位随温度变化的模型研究

Model Study on CPⅢ(Control Network Ⅲ Points) with Temperature Change for Nanjing Dashengguan Yantze River Bridge

以京沪高铁南京大胜关长江大桥CPⅢ高精密测量为工程背景,经过坐标变换后计算得出各个点位的膨胀值,利用概率与统计理论分析处理,得到可用于建模的点对数据(ΔS,ΔT)。根据一定的假设条件,建立了测量点位的位移随环境温度变化的线性回归模型,从而得出大桥CPⅢ位置POS与温度T之间的关系。利用该模型修正并评价测量数据,结果表明其较差完全符合要求,区间预测模型可用。并编程实现了CPⅢ点位位置随环境温度变化的自动化预测,能够方便地为大桥的变形观测、定期复测和实际胀缩效果分析提供一定的参考。

Based on the CP Ⅲ high precision measurement of Nanjing Dashengguan Yangtze River Bridge on Beijing-Shanghai High-speed Railway,this paper calculated the expansion value of each measurement point after coordinate transformation and got the relational data of（ AS, AT） for modeling by applying probability and statistics theory. According to certain assumptions, the linear regression model of the measurement point＇s displacement with environment temperature changes is established and the relationship between point＇s CP Ⅲ position （POS） and temperature （T） is presented. By using POS-T model to revise and evaluate the measurement data, this paper concluded that the range of points fully meets the requirement and the interval forecast model is feasible. This paper also designed and realized the automatic prediction of each point＇s CP Ⅲ position with the given environment temperature by computer programming,which can conveniently provide a reference for bridge deformation observation, periodical retest and actual expansion and contraction analysis.