微动勘探技术在隧道深厚风化层勘察中的应用

Application of Micro-Tremor Technology to theDeep Weathering Layer Detection of Tunnels

为解决隧道勘察中深厚风化层界线划分问题,采用微动探测台阵技术采集地层的天然源面波信号,并采用空间自相关法处理数据获取频散曲线,从而得到能直观反映探查范围内地层的速度变化的视横波速度,再结合少量钻孔就可得到该区域内的土石分界及风化层界面。结果表明:微动探测得到的地层分界线与钻孔地层剖面结果基本一致,且起伏形态清晰,精度较高;该方法作为一种新的地层界限勘察手段,探测时无需人工震源,具有经济、高效、探测深度大、分辨率高等特点,对确定山区大型深层地质界面,探测效果良好。

In order to solve the problem of deep weathering layer boundary demarcation in tunnel survey,the natural source surface wave signal of the formation is collected by using the micro-tremor detection station array technology,and the data acquisition frequency-dispersion curve is processed by spatial self-correlation method,so as to obtain the visual and horizontal wave speed which can visually reflect the velocity change of the formation within the exploration range,and then the soil and rock mass boundary and weathering layer interface can be obtained from a small number of drilling holes in the area.The results show that the formation boundary obtained by the micro-tremor technology is basically the same as the results of the drilling formation profile,and the undulating pattern is clear and the accuracy is high.As a new method of stratum boundary survey,this method does not need artificial source as detecting,and has the characteristics of economy,high efficiency,large detection depth and high resolution.With good detection effect,it is good for determining the large-scale deep geological interface in mountainous areas.