【作者】 徐正强；

【导师】 周水兴；

【作者基本信息】 重庆交通大学 ， 桥梁与隧道工程， 2011， 硕士

【摘要】 近年来大跨度拱桥在我国得到了迅速发展,大跨度拱桥拱肋安装大多采用无支架缆索吊装斜拉扣挂法,成拱线形好坏关系着拱桥的受力状态和正常营运。受到温度误差、设计参数误差、测量误差、计算误差及施工误差等影响,拱肋实际安装线形与理论安装线形存在偏差。大量工程实践表明:温度误差对拱肋安装线形的影响较显著。本文开展了拱肋安装线形误差适时调整技术研究,主要内容如下:①分析拱肋安装线形误差成因。②针对温度误差对拱肋安装线形影响显著的特点,研究了拱肋吊装中季节温差对拱肋安装线形的影响,得到了拱肋安装线形随季节温差的变化规律。③引入贝叶斯气温预测模型,进行长期温度预测,通过某地历年气温的预测,验证了贝叶斯气温预测模型的可行性和合理性。④给出了拱肋安装误差容许范围的确定方法,在此基础上提出一种拱肋安装线形误差适时调整方法。针对拱脚不同的边界条件,研究了线形误差调整方法,包括影响矩阵法、优化计算法及顶推法。⑤以某桥为例,运用ANSYS的零阶优化法,采用贝叶斯气温预测模型预测了拱肋节段安装温度,计算了不计温差影响和计入温差影响的节段预抬量和索力。结果表明:大跨度拱桥在计入温差影响后,索力值差异较小,但预抬量差异较大。计入温差影响后,拱肋成拱线形与目标线形吻合良好,说明该方法能够解决拱肋安装中温度误差对拱肋安装线形及内力影响较大的问题,具有较高的实际工程应用价值。更多还原

【Abstract】 Long-span arch bridge have developed rapidly in China in recent years, The installation of main arch in Long-span arch bridge is mainly cable-stayed suspension method, the into-arch alignment is closely related with the status and normal operation of arch bridge. Due to the influence of temperature error, decision parameter error, measurement error, calculating error and erecting error and so on ,the actual arch rib alignment is different with the theory. A large number of practice shows that temperature error has obvious effects on the arch rib installation alignment.This paper study the technology of the alignment error for arch installation timely adjustment, the main contents are as follows:①Classify the error for the reason of the formation of alignment error during arch rib installation.②The influence of seasonal temperature difference on the arch rib installation alignment during the hoisting arch rib for the characteristic that temperature error has obvious effect on the arch rib installation alignment is studied, and the change rule of arch rib installation alignment with the seasonal temperature difference is obtained.③Bring in temperature forecasting model of Byes ,carrying out the forecasting of long-time temperature, though forecasting the temperature for somewhere over the year, proving the feasible and rationality for temperature forecasting model of Byes.④The allow range of error for arch rib installation is derived, and the method of alignment error for arch installation timely adjustment is proposed. For different boundary condition at arch foot, study the adjustment method for linear error, including influence matrix method, optimization calculation method and incremental launching method.⑤Take one bridge as an example, using zero-order optimistic method of ANSYS, adopt temperature forecasting model Byes to forecast the installment temperature for arch rib segment. Calculate the cable force and pre-camber of considering the influence of temperature and without considering the influence of temperature. Result shows that cable force change little, but pre-camber change large, after considering the influence of temperature for large span bridge. Considering the influence of temperature, arching linear tallies with objecting linear well for arch rib, Illustrate that this method can solve the problem of liner and internal force effect from temperature error in arch rib installing, and have a highly application value for engineering.更多还原