多道瞬态瑞雷波技术在公路采空塌陷区探测中应用

Application of the multi-channel transient rayleigh wave method to highway goaf detection

地下采空塌陷区岩体结构具有明显的结构不连续、松散、断裂、空洞等异常结构特征,本文在分析公路采空塌陷区地球物理场特征的基础上,详细讨论了应用多道瞬态瑞雷波技术探测采空塌陷区的可行性以及相关技术,深入分析基于瑞雷波波场特征、频谱结构、能量衰减、频散特征、相速度以及多阶模等特征探测和评价地层结构的均匀性、地下空洞及异常结构体等地下障碍物的存在及其空间分布的解释标志.滚动式多道瑞雷波探测技术可以有效地探测地下采空区、软弱结构体等异常结构体的赋存状态及空间分布.

The rock mass in mined-out area is characterized by abnormal structures such as primary strata structural discontinuity,loosening,fissures,caves and so on,compared with the un-mined area.On the basis of the geophysical field condition in the goaf area analyzed,the effectiveness and key measurements of the multi-channel transient Rayleigh wave method to detect mined-out area are discussed in this paper,taking the subsided highway as an example.The abandoned mines under the highway and anomalies in the mined area can significantly affect propagating and scattering of Rayleigh wave,producing an abnormal wave field and frequency-wavenumber spectral,a decrease in the major amplitude and the phase velocity of Rayleigh waves in a broad frequency range,and strong multiple modes of Rayleigh waves and so on.In conclusion,the continuous acquisition of multichannel Rayleigh wave data along linear transects has great promise in detecting location of underground goafs,collapse zones and loosening abnormalities associated with highway subsidence.