Research on the Causes Analysis and Rectification Construction Technology of High Pier Deviation of Multi-Span Prefabricated Beam Bridges in Mountainous Areas

随着公路里程增长，桥梁基础设施维护面临的挑战日益凸显，尤其是西南山区。本文分析了高墩偏位的多种影响因素，如外荷载、温度、支座安装、桥下填土及初始几何缺陷等。结合实际桥梁案例分析表明，支座安装不当是导致桥墩偏位的关键原因。提出以主梁提供反力的墩柱纠偏新方法，详细阐述反力架安装与滑动面建立、顶推计算及施工控制等技术要点。依托实际桥梁，对偏位的桥墩实施纠偏，并通过有限元模拟与现场监测，对该纠偏方法进行验证。结果表明，该方法有效提升纠偏效率与安全性，控制精度高，为解决桥墩纠偏难题提供了可靠方案，对保障桥梁运营安全具有重要意义。With the increase in the mileage of highways, the challenges faced in the maintenance of bridge infrastructure have become increasingly prominent, especially in the mountainous areas of Southwest China. This paper analyzes various influencing factors of the deviation of high piers, such as external loads, temperature, bearing installation, filling under the bridge, and initial geometric defects. The analysis combined with actual bridge cases shows that improper bearing installation is the key cause of pier deviation. A new method for rectifying pier column deviation by using the main beam to provide reaction force is proposed, and the technical key points, such as the installation of the reaction frame, the establishment of the sliding surface, jacking force calculation, and construction control, are elaborated in detail. Relying on an actual bridge, the deviation of the piers is rectified, and the rectification method is verified through finite element simulation and on-site monitoring. The results show that this method can effectively improve the rectification efficiency and safety, with high control precision. It provides a reliable solution to the problem of pier rectification and is of great significance for ensuring the safe operation of bridges.