小半径大跨度体外预应力钢混组合梁桥设计研究

Design Research on External Prestressing Steel-concrete Composite Beam Bridge with Small Radius and Large Span

通过介绍城区改造项目地理位置,拟定桥梁设计方案,阐述了狭小空间互通桥梁的设计理念。在跨路净空受限的条件下,钢混组合梁极大限度降低梁高。结合有限元计算分析,拟定钢梁和混凝土桥面板尺寸,并采用主梁箱体内施加体外预应力的方式,增加主梁抗弯、抗剪承载力及主梁刚度,从而改善小半径、大跨度跨路桥梁的受力状态,为类似交通改造工程的桥梁设计提供参考。

The design scheme for the bridge is formulated by introducing the geographical location of the urban renovation project,and the design concept of interchange bridge with narrow space is elaborated.Under the condition of limited cross road clearance,the steel-concrete composite beam greatly reduces the beam height.In combination with the finite element computational analysis,the dimensions of steel beams and concrete bridge decks are determined,and external prestressing is applied inside the main beam box to increase the flexural capacity and shear capacity and stiffness of the main beam,so as to improve the stress state of the road crossing bridge with small radius and large span,and provide reference for the bridge design in similar transportation renovation projects.