透射槽波能量衰减系数成像与陷落柱探测

Tomography of transmission in-seam wave attenuation coefficient and detection of collapse columns

为了实现工作面内陷落柱的精确探测,克服坑透法成像分辨率过低的不足,对透射槽波能量衰减系数的CT成像技术展开研究。利用新型矿井无缆自记式地震仪开通道数不受限制的特点,提高成像区域的射线覆盖次数;采用带有平滑约束的代数重建算法,实现探测区透射槽波能量衰减系数成像,并在王坡煤矿3204工作面部分区域开展试验。结果表明:透射槽波能量衰减对陷落柱有明显的反映,成像结果能够清晰反映煤层中陷落柱位置与边界,为准确探测陷落柱发育情况提供依据。

In order to precisely detect collapse columns in coal mining face, and overcome the weakness in resolution of radio tunnel tomo- graphy, the authors studied the technology of transmission in-seam wave attenuation tomography.Taking advantage of the new type of selfrecording mine seismograph,the number of geophones was unlimited and the density of rays between shot and geophones was increased. Based on this equipment,this paper discussed the ART algorithm with a smoothness constraint to achieve tomography of transmission inseam wave attenuation.The new equipment and method was applied in the detection of collapse columns lay in the No.3204 Coal Mining Face of Wangpo Coal Mine.The result shows that attenuations of transmission in-seam waves are sensitive to collapse columns.The result of tomography can distinctly reflect the positions and boundaries of collapse columns in coal seam.It provides the basis to accurately determinate properties of collapse columns.