磁性源地面-巷道瞬变电磁超前探测响应特征研究

发布时间：2018-03-10 18:26

本文选题：瞬变电磁法　切入点：超前探测　出处：《中国矿业大学》2017年硕士论文　论文类型：学位论文

【摘要】：为防止突水事故的发生,巷道(隧道)掘进过程中需查明掘进工作面前方隐伏的地质构造,提前采取治理措施。鉴于地面瞬变电磁法和矿井瞬变电磁法各自优点,提出磁性源地面-巷道瞬变电磁超前探测技术,旨在实现巷道(隧道)掘进突水灾害实时动态监测。本文通过理论计算,分析了大矩形源瞬变电磁场的地下分布特征,为源的合理布置提供了依据;采用数值模拟,研究了典型导含水构造在磁性源地面-巷道观测方式下瞬变电磁场的响应特征。主要结论如下:(1)地面-巷道瞬变电磁法感应电动势响应曲线一般呈先上升后下降的变化趋势,随着观测点深度的增加,初始值和极值减小,达到极值所用时间延长。(2)对于低阻异常体,感应电动势初始响应值低于不含异常体时均匀半空间响应值,响应曲线达到极值而后衰减时,则大于不含异常体时的均匀半空间响应值;高阻异常体的响应变化趋势与低阻异常体相反。(3)陷落柱模型中,水平分量y感应电动势响应幅值与特征由其水平分布位置决定,水平分量x和垂直分量z感应电动势由其纵向发育的高度决定。因此,可以通过y分量响应幅值变化判断陷落柱的大体平面位置,通过x和z分量响应幅值大小的相对变化判断陷落柱的纵向发育情况。(4)积水采空区模型中,水平分量x和垂直分量z感应电动势响应幅值的变化由其积水范围的大小决定,水平分量y感应电动势响应曲线特征与幅值的变化由其空间水平位置决定。因此,可以通过x分量和z分量感应电动势响应幅值大小的相对变化判断积水采空区的范围,通过y分量感应电动势响应曲线特征与幅值的变化判断积水采空区的大体平面位置。(5)断层模型中,水平分量y感应电动势响应曲线的特征与幅值大小变化主要由其走向决定,水平分量x和垂直分量z感应电动势响应曲线特征与幅值的大小主要由其倾向决定,水平分量x要比垂直分量z感应电动势的响应更加灵敏。因此,可以通过y分量响应特征与幅值的相对变化判断断层的走向发展,可以通过x分量和z分量响应幅值的变化情况判断断层倾向的发展。(6)在某矿的掘进工作面中开展了磁性源地面-巷道瞬变电磁超前探测方法的实际探测试验,结果表明该方法探测掘进工作面前方导含水构造切实可行,同时通过瞬变电磁感应三分量的响应特征可以定位异常体的位置。
[Abstract]:In order to prevent water inrush accidents, it is necessary to find out the hidden geological structure in front of the tunneling face during the tunneling process, and take measures to control it in advance. In view of the respective advantages of the ground transient electromagnetic method and the mine transient electromagnetic method, In order to realize the real-time and dynamic monitoring of water inrush disaster in roadway (tunnel) tunneling, this paper puts forward the technique of magnetic source ground-roadway transient electromagnetic advance detection. Through theoretical calculation, the underground distribution characteristics of large rectangular source transient electromagnetic field are analyzed in this paper. It provides the basis for the reasonable arrangement of the source, and uses the numerical simulation, In this paper, the response characteristics of transient electromagnetic field in typical water-conducting structures under the observation mode of magnetic source ground-roadway are studied. The main conclusions are as follows: 1) the response curve of inductive EMF of ground-roadway transient electromagnetic method generally shows a tendency of rising first and then decreasing. With the increase of the depth of observation point, the initial value and extreme value decrease, and the time to reach the extreme value is prolonged. 2) for the low resistivity abnormal body, the initial response value of induction EMF is lower than the uniform half space response value without abnormal body. When the response curve reaches the extreme value and then attenuates, it is larger than the uniform half space response value without abnormal body, and the response trend of high resistivity abnormal body is opposite to that of low resistivity anomaly body. The amplitude and characteristics of the response of the horizontal component y induced EMF are determined by its horizontal distribution position, and the horizontal component x and the vertical component z induced EMF are determined by the height of their longitudinal development. The general plane position of the collapse column can be judged by changing the amplitude of the y component response, and the longitudinal development of the collapse column can be judged by the relative variation of the magnitude of the response amplitude of x and z components. The response amplitude of horizontal component x and vertical component z inductive electromotive force is determined by the magnitude of its hydrostatic range, and the characteristic and amplitude of the response curve of horizontal component y induction EMF are determined by its spatial horizontal position. The range of the goaf can be determined by the relative variation of the amplitude of the response of the x component and z component induction EMF. According to the change of y component induced EMF response curve and amplitude, the characteristics and amplitude of the response curve of horizontal component y induced EMF are mainly determined by its strike in the fault model. The characteristics and amplitude of the response curves of horizontal component x and vertical component z induced electromotive force are mainly determined by their tendency, and the horizontal component x is more sensitive than the vertical component z induced electromotive force. The strike development of faults can be judged by the relative variation of the response characteristics and amplitude of the y component. The development of fault tendency can be judged by the variation of x component and z component response amplitude.) the actual detection test of magnetic source ground-roadway transient electromagnetic advance detection method has been carried out in the driving face of a certain mine. The results show that the method is feasible to detect the water-bearing structure in front of the tunneling face, and the location of abnormal body can be located by the response characteristics of three components of transient electromagnetic induction.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD745;P631.325

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