纵横抬梁法加固线路施工安全控制措施

Construction Safety Control Measures of Railway Reinforced by Longitudinal and Transverse Beams Lifting Method

省道S103在K982+008处采用8~18 m不同跨度的连体框构桥下穿既有瓦日(瓦塘—日照)双线铁路。由于瓦日铁路上下行线间距为4 m,无法使用D型便梁,最终确定采用纵横抬梁法加固线路。首先对横梁最大容许跨度进行计算,然后采用MIDAS/Civil建立数值模型,对中-活载作用下纵梁、横梁的竖向位移进行了分析。发现工字钢横梁变形较大,该处是加固体系的薄弱部位。据此提出严控土方开挖量和顶进步距、加强纵横抬梁加固体系关键处所的检查和整修、对轨道竖向位移实时监测三项控制措施。经实施,竖向位移变化总体可控。

Provincial highway S103 adopts a conjoined frame bridge with different spans of 8~18 m to pass under the existing Watang-Rizhao double-track railway at K982+008.Since the distance between the upgoing and the downgoing railways of Watang-Rizhao railway is 4 m,it is impossible to use D-type temporary beam,so the longitudinal and transverse beam slifting method is finally adopted to reinforce the railway.Firstly,the maximum allowable span of the transverse beam was calculated,the numerical model was established by using MIDAS/Civil to analyze the vertical displacement of longitudinal and transverse beams under China-live load.It is found that the deformation of I-beam is large,which is the weak part of the reinforcement system.Based on this phenomenon,three control measures were put forward,which are to strictly control the volume of earth excavation and the jacking distance,to strengthen the inspection and renovation of the key parts of the longitudinal and transverse beams lifting reinforcement system,and to monitor the vertical displacement of the track in real time.After implementation,the change of vertical displacement is generally controllable.