基于UHPC材料的高架小箱梁接缝设计优化与施工技术研究

Optimization of Joint Design and Study of Construction Technology for Elevated Small Box Girder Based on UHPC Material

随着社会经济的不断发展,社会对城市高架的建设要求越来越高,城市高架快速化建设将是城市高架的发展趋势。小箱梁桥作为重要桥型之一,在城市高架桥中有着广泛应用,因而实现小箱梁快速化施工有着十分重要的意义。实现小箱梁快速施工的关键在于小箱梁接缝。传统的小箱梁接缝构造复杂,施工流程繁琐,且受力性能较差。本文针对传统小箱梁接缝存在的施工和受力性能问题,结合UHPC材料的性能优势,引入了UHPC接缝概念,并以宁波机场快速路南延工程建设项目为背景,针对UHPC接缝设计关键参数,提出了背景工程中小箱梁UHPC接缝的构造设计并优化。同时,总结了小箱梁UHPC接缝施工流程,明确了小箱梁UHPC接缝关键施工工艺和施工方法,对UHPC接缝施工质量控制提出了具体的要求。

With the continuous development of social economy,the society has higher and higher requirements for the construction of urban viaduct.The rapid construction of urban viaduct will be the development trend of urban viaduct.As one of the important bridge types,the small box girder bridge is widely used in urban viaduct.Therefore,it is very important to realize the rapid construction of small box girder.The key to realize the rapid construction of small box girder is the joint of small box girder.The traditional small box girder joint structure is complex,the construction process is tedious,and the mechanical performance is poor.Aiming at the construction and mechanical performance problems of traditional small box girder joints,combined with the performance advantages of UHPC materials,the concept of UHPC joints is introduced.Taking Ningbo airport Expressway South Extension Project as the background,aiming at the key parameters of UHPC joint design,the structural design and optimization of UHPC joints of small box girder are proposed.At the same time,the construction process of UHPC joint of small box girder is summarized.The key construction technology and construction method of UHPC joint of small box girder are defined.The specific requirements for the construction quality control of UHPC joint are put forward.