可展式铁路抢修梁的技术方案研究与力学分析OA

In order to solve the problems of low strength and rigidity,slow traffic speed,long time for assembling,and inconvenient storage and transportation of existing railway emergency repair girder,based on the characteristics of deployable structure,a technical scheme and erection method for deployable railway emergency repair girder were proposed:Through the longitudinal assembly of different numbers of intermediate frames and adjusting the unfolded state of the frame,the emergency repair girder can be adapted to the emergency repair of bridges with a span of 32 m and 24 m;with the assistance of small machines,the guide girder erection can be achieved to speed up the repair progress.The finite element model of the 32 m-span emergency repair girder was established by ANSYS software,and the static analysis and modal analysis of the emergency repair girder were carried out;The multi-body dynamics models of C70 freight train and CRH380A high-speed train are established by UM software,and the vehicle-bridge coupling vibration analysis for the emergency repair girder was carried out.The results show that:The mid-span top chord,the right inclined web member at the girder end and the pin at the girder end control the safety of the emergency repair girder;The first-order natural vibration frequency of the emergency repair girder is 5.965 Hz,and the corresponding mode shape is lateral bending,indicating that the lateral stiffness of the emergency repair girder is weak;The heavy train formation is disadvantageous to the bridge response,and the empty train formation is disadvantageous to the vehicle response;The indexes that affect bridge safety and vehicle safety increase nonlinearly with the increase of train speed.Through analysis,the mechanical properties of the deployable emergency repair girder meet the requirements of relevant specifications,and freight trains and high-speed trains can safely pass through the emergency repair girder at a speed of up to 60 km/h and 100 km/h respectively.