地质雷达在昆仑山隧道病害检测中的应用

APPLICATION OF GROUND PENETRATING RADAR TO DISEASE DETECTION OF KUNLUN MOUNTAIN TUNNEL

青藏铁路全线开通运营已近4a时间,为掌握隧道的实际运营状态,特对处于高寒地区永久冻土隧道之一的昆仑山隧道的病害状况进行无损检测。为不影响隧道正常运营,在无列车通过期间采用地质雷达进行检测。检测结果表明:隧道在高寒恶劣环境中,衬砌总体外观质量不佳,在两端洞口段有渗水疏松掉块现象;衬砌背后空洞缺陷等级为严重、极严重地段的测线长度分别为59和61m,分别占总测线长度的0.70%和0.72%;衬砌背后回填不密实缺陷等级为严重地段测线长度为10m,占总测线长度的0.12%。检测数据同时也表明,温度和冻胀因素使处于高寒恶劣环境中的隧道更容易发生病害,严重影响耐久性。检测结果为隧道正常运营和以后的病害治理提供可靠的依据。

Opening and operation of Qinghai—Tibet Railway line has almost been 4 years. In order to obtain the actual operating state of the tunnel,Kunlun Mountain tunnel,one of the permafrost tunnels in the cold plateau region,is detected by soundness diagnosis testing method. In order to keep the normal operation of the tunnel,the ground penetrating radar is used to detect tunnel damage during the absence of train. The detection results show that the general appearance of tunnel lining is in poor quality in the cold plateau environment,and the phenomena of fall-block and seepage appear at both ends of it. The lengths of detected line for empty defect behind the lining reaching serious and very serious level are 59 and 61 m separately,both of which take up the total tested length of 0.70% and 0.72%,respectively;the detected length of backfill undense defect as serious level is 10 m,taking up 0.12% of the total detected line length. Furthermore,test data also indicate that the tunnel in plateau-frozen atrocious environment is more prone to occur disease due to temperature and frost force;and the durability of tunnel is affected seriously. The detected results can provide reliable basis for normal operation and disease management of the tunnel in the future.