考虑地面动荷载的地铁运行隧道结构安全分析

中铁第一勘察设计集团有限公司,陕西 西安 710043

机车动荷载; 地铁运行震动; 地层动应力; 加速度响应; 浮置板道床

Safety analysis of the tunnel structure during metro operation with ground dynamic load taken into account
LIU Xin-jun

(China Railway First Survey and Design Institute Group Co.,Ltd.,Xi'an 710043,China)

locomotive dynamic load; subway operation vibration; stratum dynamic stress; acceleration response; floating track bed

DOI: 10.13800/j.cnki.xakjdxxb.2017.0205

备注

为研究地铁开通运行后对地面建构筑物的影响及上部铁路动荷载情况下对地铁隧道结构的影响,采用理论计算和数值模拟相结合的方法,对南京地铁4#线下穿京沪高铁联络线和宁芜铁路路基段进行了探讨和分析,研究了地铁运行震动和铁路机车动荷载情况下地层的动应力分布及变化规律,进一步分析运行状态下两者的相互影响情况。结果 表明:高铁震动引起的土体动应力较大,并对隧道结构产生不利影响,高铁列车通过隧道上方时隧道顶部加速度的变化幅值明显变大,说明隧道管片对高铁列车运行产生的动荷载较为敏感,相比之下对普通列车产生的动荷载的敏感性不强。为确保地铁运行后结构的安全,隧道在设计时采取了安设高强度螺栓,浮置板道床以及在管片上增设注浆孔等工程措施。

In order to study the impact of subway operation on ground construction,as well as the influence of upper railway on the structure of metro tunnels in the case of dynamic load,this paper discusses and analyses the subgrade of Beijing-Shanghai high-speed rail and Ning-Wu railway under-passed by the Nanjing metro line four through combining theoretical calculation with numerical simulation,and study dynamic stress distribution and change law of the stratum under the circumstances of subway operation vibration and dynamic load of railway locomotive,and further probe into the interaction under the operation state.Extensive experimental results show the soil dynamic stress is larger caused by high-speed rail vibration which bring adverse effects on the tunnel structure.The change amplitude of the top tunnel acceleration obviously becomes larger when the train passes through the tunnel,which indicates that the tunnel segment is more sensitive to the dynamic load caused by the operation of high-speed railway in contrast to the weak sensitivity to the ordinary train.Therefore,in order to ensure the safety of the structure during operation,the tunnel was designed with high strength bolts,floating track bed,and engineering measures that adding grouting hole on segment.