帕德玛大桥节段箱梁预制架设与线形控制

Precast-erection construction and alignment control of segmental beam of bangladesh padma bridge railway connection line

为分析研究短线法节段预制拼装箱梁施工技术和施工控制方法,依托孟加拉帕德玛大桥铁路连接线,介绍了该项目节段预制和架设施工关键技术,计算分析预制架设施工关键过程结构的应力和变形情况,应力计算结果表明结构在施工过程中安全可靠,位移计算结果为预制阶段预拱度设置和梁长控制提供依据。提出待浇梁段长度负误差动态控制法,后续架设阶段跨间接缝宽度偏差较小,验证了单个梁段及单跨总梁长预制控制计算方法的有效性,结果表明:预制线形误差基本控制在±3 mm内,架设线形误差最大5.8 mm,控制精度较高,施工和控制经验可为同类桥梁施工提供借鉴参考。

To analyze and study the construction technology and construction control method of segment prefabrication and assembling box girder by short-line method,based on the railway connection line of Bangladesh Padma Bridge,this paper introduces the key technology of segment prefabrication and erection construction,the stress and deformation of the structure in the key process of construction are calculated and analyzed.The stress calculation results show that the structure is safe and reliable in the construction process,the displacement calculation results provide the evidence for the pre-camber setting and beam length control in the prefabrication stage.The dynamic control method of negative error for the length of the uncast beam segment to be is put forward,and the smaller deviation of the width of the joint between spans in the subsequent erection stage verifies the validity of the precast control calculation method for the length of single beam segment and single span total beam.The results show that the precast alignment error is basically controlled within±3 mm,the maximum alignment error is 5.8 mm,and the control precision is high.The experience of construction and control can provide reference for similar bridge construction.