京沈客运专线先张Ⅲ轨道板张拉结构研究与设计

Research and Design on Tension Structures of Pretensioning Type Ⅲ Track Plates of Beijing-Shenyang Passenger Dedicated Railway

京沈客运专线无砟轨道结构为Ⅲ型双向先张预应力混凝土轨道结构,板内纵横向双向预应力张拉的特殊性决定了张拉台座和张拉钢横梁与一般的单向张拉结构不同,需要对其进行专门研究与设计。文章依据混凝土结构设计原理并结合有限元单元法,设计了顶推式张拉钢横梁与框架式张拉台座,分析计算得到了张拉结构的一系列反应信息,包括变形、应力以及内力等。研究表明,设计的张拉结构经济适用,能满足轨道板预应力筋张拉生产的需要。且对框架式地梁进行了配筋设计与抗裂度验算,保证了张拉结构的安全可靠。该张拉结构已成功应用于京沈客运专线轨道板预制工程中。

The structure of ballastless track of Beijing-Shenyang passenger dedicated line is pretensioning type Ⅲ twoway prestressed Concrete Track. Due to the special nature of the vertical and horizontal two-way Prestressed tension in the plate, the tension bench and tension steel beams are different from the general structure of unidirectional tension, so specialized research and design are needed. In this paper, based on the design principles of concrete structure and the finite element method, push-type tension steel beams and framed tension bench are designed. Through analyses and calculations, a series of reactions information of tension structures, including deformation, stress and internal force, are obtained. The results show that： the designed tension structures are economical and suitable, which can meet the needs of production of the prestressed reinforcement of the track panels. While reinforcement design and checking crack resistance of framed beams are completed to ensure safety and reliability of the tension structures. This tension structure has applied to the prefabrication of the track plates of Beijing-Shenyang passenger dedicated line.