摘要
国内外的隧道地质超前预报技术正在发展之中,目前TSP203技术在中国的用户较多,它采用一维观测系统,获得的地震资料是零偏移距反射道集,不能准确确定掌子面前方围岩的波速分布,也不能准确推定反射地质界面的位置和力学性状,造成很多漏报和误报,亟待改进。作为改进对策,TST隧道超前预报技术采用二维和三维观测系统和偏移成像处理技术,利用不同偏移距的共散射点道集,同时利用走时和振幅等运动学和动力学信息,准确确定掌子面前方围岩速度分布、反射地质构造的准确位置和界面两侧围岩力学性状的差异,具有坚实的物理基础,克服了TSP203技术的缺陷,大大地提高了超前预报的准确性和可靠性,降低了预报的风险。
Current methods of tunnel geological prediction are developing at home and abroad. By TSP 203 method, the observation is made along a line, and only zero off-set seismic data are obtained , so it is hard to accurately determine the seismic velocity distribution of wall rock,to find the accurate position of geological interface, and to recognize the mechanical difference between two side rocks of the reflector. Therefore, from these defec- tive techniques, this paper proposes TST method with 2D and/or 3D observation and data process of migration image and travel time inversion image, which solves the problem of analyzing velocity structure of wall rock in the front of tunnel face and realizes accurate image of geological framework of tunnel wall rock. This method is fit for geological prediction under complex geological condition.
出处
《工程地球物理学报》
2008年第3期266-273,共8页
Chinese Journal of Engineering Geophysics
关键词
隧道超前预报
TSP203技术
零偏移距道集
TST
波速分析
偏移成像
tunnel geological prediction
TSP203
zero off-set gather
TST technology
seismic velocity analysis
seismic migration image
