采用外套钢管保护的系杆拱桥吊杆更换技术研究

朱军，曹文斌，朱利明，易晨阳

摘要:

本文依托某系杆拱桥吊杆更换项目,对比分析几种吊杆更换施工方法,在充分考虑安全性、经济性以及本次工程吊杆有外套钢管的特殊性,选定合适的吊杆更换方法。为保证吊杆更换施工全过程结构变形、受力合理,建立全桥有限元模型对吊杆更换施工过程进行计算,并确定外套钢管切割及焊接的合理工序,从而制定详细的更换施工步骤。现场施工过程中,对吊杆内力、钢管内力、拱肋和系梁应力及变形进行施工监控,监控结果表明,直接更换法适用于本工程,可为此类工程提供参考。

Abstract:

SBased on the suspender replacement project of a tied arch bridge, this paper compares and analyzes several suspender replacement construction methods, and selects the appropriate suspender replacement method after fully considering the safety, economy and the particularity that the suspender of this project has an outer steel pipe. In order to ensure the reasonable structural deformation and stress in the whole process of suspender replacement construction, a full bridge finite element model is established to calculate the suspender replacement construction process, and determine the reasonable process of cutting and welding of outer steel pipe, so as to formulate detailed replacement construction steps. During the on-site construction, the internal force of suspender, internal force of steel pipe, stress and deformation of arch rib and tie beam are monitored. The monitoring results show that the direct replacement method is suitable for this project and can provide reference for such projects.