斜拉桥组合梁桥面板体内体外预应力体系比选研究

Comparison & Selection of Internal & External Prestressing System for Composite Beam Deck of Cable-Stayed Bridge

为确定斜拉桥组合梁混凝土桥面板预应力体系对桥面板抗裂性能的改善程度,以宁波中兴大桥为工程背景,通过制定比选研究对象,分析、介绍组合梁在配置体外束和体内束体系下的结构位移、混凝土板应力分布和预应力在混凝土板和钢梁中轴力分配比例等研究结论。结果表明,2种配束方式下结构效应均满足规范要求,通长布置纵向体外预应力组合梁结构性能稍优。

In order to determine the improvement degree of concrete deck prestressing system of composite beam of cablestayed bridge on the crack resistance of deck,this paper takes Ningbo Zhongxing Bridge as an engineering background, and through making a comparative study object, analyses & introduces the structural displacement, stress distribution of concrete slab and the proportion of prestressing force distribution in concrete slab and steel beam of composite beam with external & internal tendons. The results show that the structural effects of the 2 modes meet the requirements of the code, and the structural performance of longitudinal external prestressing composite beams with through-length arrangement is slightly better.