高速铁路分片式槽形梁设计研究

Design Research of High Speed Railway Sliced Trough Girder

综合考虑铁路建筑限界、桥面横向布置、戈壁大风区桥梁施工条件、列车运营安全等因素,兰新高速铁路百里风区桥梁采用了并置16 m分片式槽形梁的设计方案。通过纵向整体杆系结构及空间三维实体有限元整体性分析,研究槽形梁的空间受力特性;通过风-车-桥耦合动力模型计算,分析槽形梁上高速列车运行安全性及平稳性。结果表明:槽形梁纵向按照全预应力构件设计、横向按照钢筋混凝土结构设计的理念可行;通过合理布置钢筋能够有效满足U形梁的抗扭承载能力;桥梁的振动性能良好,具有足够的竖向和横向刚度,能够满足高速铁路桥梁250 km/h运行时的安全性和舒适性要求。

In view of multiple factors including railroad construction clearance,transverse layout of bridge deck,construction conditions of bridge in Gobi gale area and safety of train operation,the design scheme of collocated 16 m sliced trough girder was adopted for the bridge in hundred-mile wind area of Lanzhou-Xinjiang high speed railway.Through the analysis of longitudinal integral link structure and f inite element integrality of spatial 3D entity,the spatial stress characteristics of the trough girder were researched.Through wind-vehicle-bridge coupled dynamic simulation,the safety and stability of high-speed train on trough girder was analyzed.The results show that the design concept of trough girder is feasible.The trough girder is designed according to full prestressed concrete member in longitudinal direction and reinforced concrete structure in horizontal direction.The torsional bearing capacity of U-shaped beam can be effectively satisf ied by reasonable layout of reinforcing bars.The trough girder has good vibration performance and suff icient vertical and transverse stiffness,which can meet the safety and comfort requirements of 250 km/h operation of high-speed railway bridges.