新型装配式倒T形空心板桥设计

Design of a New Type Invertible T-Shaped Voided Slab Bridge

针对铰接空心板桥的铰缝病害问题,结合国内装配式空心板桥的发展趋势:增大现浇构造、在结合面处增设延缓或阻止其裂缝开展的构造措施,提出了一种由预制倒T形空心板、现浇结构层和钢板构造组成的新型倒T形空心板桥。通过试验和有限元分析了桥梁的荷载横向分布规律,结果表明:建议采用G-M法计算倒T形空心板桥荷载横向分布系数;采用"梁格法"建立倒T形空心板桥的杆系有限元模型;给出了施工与成桥阶段应力验算、受力薄弱部位验算等设计计算建议;最后,提供了一座16 m跨径的简支钢筋混凝土倒T形空心板桥的设计算例。

This paper focus on the hinge joints problem in hinged hollow slab bridge.After analyzing the development trends of hinged hollow slab bridge in China which are increasing the cast-in-place structure and adding structural measures to delay or prevent the crack development at the junction surface,a new type of bridge structure-inverted T-shaped voided slab bridge is proposed.It is composed of precast T-shaped voided slab,cast-in-place structural layer and steel plate structure.The rule of load transverse distribution is analyzed by experiment and finite element(FE)analysis.It is show that G-M method is more suitable for load transverse distribution analysis of inverted T-shaped voided slab bridge.The grillage method is suggested for FE modeling of inverted T-shaped voided slab bridge.The design calculation proposal including stress checking in construction and finished stages,checking calculation of stress weakness positions are provided.The design example of a simply supported inverted T-shaped voided slab bridge with main span of 16 m is also provided.