高速铁路跨度40m预应力混凝土简支箱梁技术经济性研究

Technical and Economic Research on 40 m Simply Supported Box Beam of High-speed Railway

高速铁路40 m简支箱梁丰富了标准梁跨度序列,对提高桥梁跨越能力、提升铁路桥梁建造水平具有重要意义。系统介绍40 m简支箱梁的研究背景、结构设计及其主要技术创新,全面开展40 m梁与现行32 m梁通用图、盐通32 m梁的技术经济性对比分析及联调联试实测验证。研究结果表明:静力性能方面,40 m梁基频小于32 m梁,静活载挠跨比和梁端转角大于32 m梁,残余徐变上拱与32 m梁相当;动力性能方面,轮重减载率比32 m梁有所增加,其余动力参数基本相当;经济性方面,梁部造价分别增加0.07万元/m和0.23万元/m,在高桥墩及跨越湖泊、河滩等情况下,40 m梁相对于32 m梁具有一定的经济优势。提出全面收集建设运营数据、加强理论研究、40 m简支箱梁可按抗震设防类别C类设计等建议。

The 40m simply supported box beam of high-speed railway enriches the standard beam span sequence, which is of great significance for improving the spanning capacity of bridges and improving the level of railway bridge construction. This paper systematically introduces the research background, structure design and main technological innovation of 40 m simply supported box beam. The technical and economic comparison analysis is carried out between the 40 m beam and the current 32 m beam and the Yantong 32m Beam, and joint debugging and joint test verification is conducted. The results show that: in terms of static performance, the fundamental frequency of the 40 m beam is less than the 32 m beam, its deflection/span ratio and beam end rotation angle are greater than those of 32 m beam, and its residual creep is equivalent to that of 32 m beam;in terms of dynamic performance, its wheel load reduction rate is higher than that of 32 m beam, and the rest of its dynamic parameters are basically same to that of 32 m beam;in terms of economy, the cost of 40 m beam is increased by 700 Yuan/m and 2300 Yuan/m respectively;and in the case of high bridge piers crossing lakes and river beaches, 40 m beam have certain economic advantages over 32 m beams. Finally, this paper puts forward some suggestions as comprehensively collecting construction and operation data, strengthening theoretical research, and designing 40 m beam according to seismic fortification category C.