地基低速层的瞬态瑞利波法数值模拟
|
摘要
针对面波勘探法探测低速层所提取的频散曲线特征进行研究。采用FLAC3D建立模型,模拟瞬态面波法提取面波信号,并用f-k法对频散曲线提取及速度剖面绘制,分析频散曲线呈"之"字形原因,验证了瞬态面波法探测低速层效果较好。
In this paper, the characteristics of dispersion curves and test results were studied when detecting the low velocity layer by Rayleigh wave method. The model was set up using FLAC3 D software. The transient Rayleigh wave method was simulated to acquire surface wave signal. The frequency dispersion curve was extracted by F-K method and the velocity profile was drawn. The reason why the frequency dispersion curves were zigzag was discussed, and the results revealed it's helpful to detecting the low velocity layer by transient Rayleigh wave method. Provide a reference for detecting the low velocity layer or soft layer by transient Rayleigh wave method.
In this paper, the characteristics of dispersion curves and test results were studied when detecting the low velocity layer by Rayleigh wave method. The model was set up using FLAC3 D software. The transient Rayleigh wave method was simulated to acquire surface wave signal. The frequency dispersion curve was extracted by F-K method and the velocity profile was drawn. The reason why the frequency dispersion curves were zigzag was discussed, and the results revealed it's helpful to detecting the low velocity layer by transient Rayleigh wave method. Provide a reference for detecting the low velocity layer or soft layer by transient Rayleigh wave method.
引文
[1]Ganji V, Gucunski N, Maher A. Detection of underground obstacles by SASW method—numerical aspects[J].Journal of geotechnical and geo-environmental engineering, 1997, 123(3):212-219.
[2]贾学明,杨建国,赖思静.路基边界对瑞利波检测影响的数值模拟研究[J].岩土力学,2004(S2):256-259,264.
[3]Cho Y S, Lin F B. Spectral analysis of surface waves in single and multi-layer slabs with finite thickness using finite element modeling[J].NDT&E International,2005,38(3):195-202.
[4]熊章强,张大洲,秦臻,等.瑞雷波数值模拟中的边界条件及模拟实例分析[J].中南大学学报:自然科学版,2008,39(4):824-830.
[5]熊章强,张大洲,肖柏勋,等.裂缝介质中瑞雷面波传播的渐变非均匀交错网格数值模拟[J].湖南大学学报(自然科学版),2008,35(8):24-28.
[6]唐圣松.二维起伏地表模型瑞雷波场正演研究[D].长沙:中南大学,2009.
[7]张碧星,鲁来玉,鲍光淑.瑞利波勘探中"之"字形频散曲线研究[J].地球物理学报,2002, 45(02):263-274.
[2]贾学明,杨建国,赖思静.路基边界对瑞利波检测影响的数值模拟研究[J].岩土力学,2004(S2):256-259,264.
[3]Cho Y S, Lin F B. Spectral analysis of surface waves in single and multi-layer slabs with finite thickness using finite element modeling[J].NDT&E International,2005,38(3):195-202.
[4]熊章强,张大洲,秦臻,等.瑞雷波数值模拟中的边界条件及模拟实例分析[J].中南大学学报:自然科学版,2008,39(4):824-830.
[5]熊章强,张大洲,肖柏勋,等.裂缝介质中瑞雷面波传播的渐变非均匀交错网格数值模拟[J].湖南大学学报(自然科学版),2008,35(8):24-28.
[6]唐圣松.二维起伏地表模型瑞雷波场正演研究[D].长沙:中南大学,2009.
[7]张碧星,鲁来玉,鲍光淑.瑞利波勘探中"之"字形频散曲线研究[J].地球物理学报,2002, 45(02):263-274.