微动勘探技术在城市轨道交通勘察中的应用

Application of micro tremor technology in urban rail transit survey

微动勘探作为基于天然源的面波勘探方法,具有方便快捷、低成本、不破坏环境等优点,在城市轨道交通工程勘察中的应用越来越广泛。以武汉某轨道交通前期勘探工作为例,开展了微动勘探试验研究,采用SFLEX高保真度无线三维地震勘探数据采集系统,通过布置圆形台阵采集微动数据,借助SPAC法提取微动数据的频散特性从而反演地下介质视S波速度剖面。试验结果表明,微动探测适合于城市复杂场地环境和地磁环境的地质体探测,数据采集方便快捷,速度分层准确可靠。

Micro tremor,as an exploration method based on natural source,has the advantages of convenient,low cost,environmental friendly,so its application in the urban rail transit project becomes increasingly extensive. Test and research on micro-tremor were carried out in a pre-stage exploration of Wuhan rail transit site by using S-FLEX high-fidelity wireless 3-D seismic data acquisition system. The micro tremor data was collected through the arrangement of circular array,and the frequency dispersion curve of micro tremor data was extracted by SPAC method to inverse underground media S wave velocity profile. The results of the experiment indicate that the micro tremor is suitable for geological-detection in the complex environment of urban site and the magnetic environment,the data acquisition is convenient and velocity stratification is accuracy and reliable.