地震映像法和地质雷达法在铁路隧底岩溶探测中的应用

Application of Seismic Imaging Method and Ground Penetrating Radar Method in Karst Detection at the Bottom of Railroad Tunnels

岩溶作为铁路隧道安全运行的一大隐患,对其高效准确的探测一直是隧道缺陷整治的重点难点。地球物理方法作为一种快速无损的探测手段在铁路隧道基底隐伏岩溶探测中能提供非常有价值的信息,受制于单一方法在隧道强干扰施工环境中的局限性,致使其探测效果有限,本文利用地震映像法及地质雷达法作为基底隐伏岩溶探测方法,并采用魏格纳-威尔分布改进算法提取地震映像剖面高精度瞬时频率。结果显示,各方法在隧道基底隐伏岩溶探测中均取得了较好的效果,且利用高精度瞬时频率能高效直观地圈定出岩溶异常分布范围,平行多测线结果进一步验证了上述方法的准确性,并能探明岩溶在空间中的位置展布,且与钻孔资料验证吻合。基于综合探测方法,同时利用时频域资料圈定隧道基底岩溶分布状况,并由此指导钻孔布置,极大地提升了隧道隐伏岩溶治理的可靠性,达到了快速准确治理隧道地质隐患的目的,为隧道岩溶物探技术的应用提供了新的思路。

As a major hidden danger for the safe operation of railroad tunnels,efficient and accurate detection of karst has been a major challenge for tunnel defect remediation.Geophysical methods as a fast and non-destructive detection means in railroad tunnel basement hidden karst detection can provide very valuable information,subject to the limitations of a single method in the tunnel strong interference construction environment,resulting in its detection effect is limited,this paper uses seismic image method and geological radar method as a basement hidden karst detection method,and uses the modified Wigner-Wille distribution method to extract the seismic image profile transient frequency.The results show that each method has achieved good results in the detection of basement karst,and the distribution of karst anomalies can be efficiently and intuitively traced by using high-precision transient frequencies.Based on the comprehensive detection method and the simultaneous use of time-frequency domain data to circle the distribution of tunnel basement karst and thus guide the borehole arrangement,the reliability of the hidden karst management in tunnels has been greatly improved,achieving the purpose of rapid and accurate management of hidden tunnel geological hazards,providing a new idea for the application of tunnel karst.