郑济高铁40 m整孔预制简支箱梁应用研究

Application Research on 40-meter Full-span Precast Simply Supported Box beam of Zhengzhou-Ji’nan High-speed Railway

目前,我国高速铁路预制架设简支箱梁的最大跨度为32 m,因受运架设备的控制,跨度大于32 m的简支梁基本采用现浇法或节段拼装法施工。结合郑济铁路黄河特大桥工程,开展40 m预制架设简支箱梁的应用研究。通过计算确定梁高、截面尺寸、钢束布置等梁体设计参数,并进行静力和动力分析;研究市域铁路40 m简支箱梁设计方案,采用与高速铁路梁相同的外形及构造设计;提出钢横梁人行道方式,满足预制箱梁通过连续钢桁梁的需要;对比40 m简支箱梁预制和现浇方案工程造价,得出预制架设方案经济效益明显;引入BIM技术,创建简支箱梁的高精度BIM模型,提高制梁生产过程中的标准化。本项目是40 m预制简支箱梁在铁路上的首次工程化应用,对于指导同类型大跨度预制简支箱梁设计具有借鉴意义。

At present,the largest span of precast simply supported beam for high-speed railway in China is 32 meters.Due to the limitation of transportation and erection equipment,simply supported beams with span greater than 32 meters are basically constructed by cast-in-place method or precast segmental method.Based on the engineering background of the Yellow River Bridge on Zhengzhou-Ji’nan High-speed Railway,this paper conducts a research on the application of 40-meter prefabricated simply supported box beam.The design parameters of beam such as height,section size and layout of steel tendons are determined by calculation,and static and dynamic analysis are performed as well.The design scheme of 40-meter beams of suburban railway is studied and the same beam shape and structure design as the high-speed railway line are adopted.The method that the sidewalk is supported by steel brace is proposed to meet the need of precast box beam passing through continuous steel truss.There are obvious economic benefits by using precast segmental scheme,compared with the construction cost of cast-in-place scheme for 40-meter beam.The introduction of BIM technology and creation of high-precision BIM model of simply supported beams improve the standardization of the process of beam production to a greater extend.This project is the first engineering application of precast simply supported box beam with a span of 40-meter in railway,which is of great referential significance for guiding the design of the similar large-span precast simply supported box beams in China.