UHPC-NC预制工字梁在农村公路危桥改造中的应用  

Application of UH C-NC Prefabricated I-Beam in the Renovation of Dangerous Bridges on Rural Highways

作　　者：温建兴 李胜才 Wen Jianxing;Li Shengcai(Guangdong Heli Traffic Maintenance Technology Co.,Ltd.,Guangzhou 511400,China;Guangdong Communication Planning&Design Institute Group Co.,Ltd.,Guangzhou 510000,China)

机构地区：[1]广东和立交通养护科技有限公司,广东广州511400 [2]广东省交通规划设计研究院集团股份有限公司,广东广州510000

出　　处：《市政技术》2025年第3期67-73,79,共8页Journal of Municipal Technology

摘　　要：近30年来我国桥梁事业飞速发展,数量与规模居世界前列,但同时既有桥梁结构也面临着耐久性、安全性和适用性三大问题,特别是对于农村低等级公路桥梁上述问题尤为突出,而急需改造的大批危桥又分散在偏远地区且面临着交通不便、施工场地狭小、大型施工设备难以抵达、后期维护困难等挑战。因此,针对农村公路中、小跨径桥梁的特点与改造难点,提出了一种便于制造、运输、安装的预应力UHPC-NC预制工字梁结构。该结构借鉴了钢混组合结构的理念,在主梁拉、剪区采用UHPC,在受压区采用普通混凝土,通过优化钢束束形、支点腹板加厚,形成无腹筋结构。UHPC-NC预制工字梁具有自重轻、运输方便、安装轻巧、强度高、耐久性好、经济性好等优点,为解决偏远地区危旧桥改造加固的难题,构建了一条建设周期短、经济性好、安全耐久、后期维护成本低的有效途径,有较好的推广应用价值。In the past 30 years,bridge industry has developed rapidly in China with quantity and scale ranking among the top of the world.However,there’re three major problems of durability,safety,and applicability in existing bridge structures,especially rural low-grade highway bridges.A large number of dangerous bridges that urgently need to be renovated are scattered in remote areas with challenges such as inconvenient transportation,narrow construction sites,hard accessing of large construction equipments,and difficult maintenance in the later stage.According to the characteristics and renovation difficulties of small and medium span bridges on rural roads,a pre-stressed UHPCNC prefabricated I-beam structure that is easy to manufacture,transport,and install is proposed.This structure draws inspiration from the concept of steel-concrete composite structures,using UHPC in the tension and shear zones of the main beam and ordinary concrete in the compression zone.A non web reinforcement structure is formed by optimizing the shape of the steel bundle and thickening the web plate of the support point.UHPC-NC prefabricated I-beams have the advantages of light weight,convenient transportation,easy installation,high strength,good durability,and good economy for solving the problem of renovating and reinforcing dangerous old bridges in remote areas,which build an effective approach with short construction period,good economy,safety and durability,and low maintenance cost with good promotion and application value.

关 键 词：危桥改造 超高性能混凝土 UHPC-NC预制工字梁 中小跨径 

分 类 号：U445.72[建筑科学—桥梁与隧道工程]