【作者】 徐莹；

【导师】 姚丽；

【作者基本信息】 沈阳工业大学 ， 测试计量技术及仪器， 2009， 硕士

【摘要】 在盾构机的施工过程中,对掘进面前方的地质条件和可能的地质灾害开展超前地质预报,对隧道的正常施工和顺利贯通发挥举足轻重的作用。盾构机前地质勘探预报,是以探测地下介质电阻率的异常为基础。本课题主要研究隧道掘进检测过程中的信号处理方法,根据检测数据得出挖掘面前方介质电阻率异常体位置参数,即参数的反演和优化处理。反演最终归结为求目标函数的最小值,从数学角度上看是一个优化问题。但通常来说,大地测量和地球物理模型是强烈非线性的,参数的偏导数非常复杂,计算时间非常长。本课题采用遗传算法来进行地电模型的参数反演,此种算法无需进行复杂的偏导数计算,收敛速度较快。本课题采用遗传算法的十进制(实数)编码和二进制编码这两种编码方式来进行参数的反演运算,对这两种编码方式得到的参数反演结果进行分析比较,选择更适合本课题的编码方式。本课题以两极装置(直线测量和环状测量)下的地下球状异常体(石头)引起的视电阻率异常为模型,通过遗传算法的反演计算,分析找出更接近真实值的异常体电阻率和大地电阻率的大小,以及球状异常体的半径,地下深度和水平位置。反演过程中所用的实测数据是在实验室搭建的实验测试平台上经过实地的测量和数据采集得到的。实验测试平台的数据采集系统以LabVIEW为软件设计平台,以发射和接受电极、数据采集模块PMD1608FS和计算机构成。此系统为用户提供友好的人机交互界面,用户可以在前面板上查看采集到的波形和数据以及设置系统的采样率、采样点数和滤波方式、阶次等。通过对遗传算法的十进制和二进制两种编码方式在二极装置和中间梯度装置的地电模型下得到的参数反演结果的比较,得出十进制编码方式更适合应用在二极装置(直线测量和环状测量)的地电模型的参数反演中。更多还原

【Abstract】 The advance geological prediction of forward section geological condition and possible geological hazard make decisive factor during tunnel boring machine (TBM) operation. The forecast of geology prospecting during tunnel boring machine working is based on the detection of underground medium resistivity anomaly. The paper mainly researches the signal processing method during detection process of tunnel driving. According to the detection data, it deduces medium resistivity anomalies body positional parameters in front of a heading face. Namely, the method needs parameter inversion and optimization treatment.The final result of inversion, an optimization method in mathematics, is obtaining the minimum of the objective function. The earth measurement and earth physical model is strong nonlinear, and the partial derivative of parameter is very complex and the calculation time is very long .In the paper, the parameter inversion uses Genetic Algorithm (GA),the algorithm do not need complex partial derivative calculation and the speed of convergence is very fast. GA uses binary and decimal system coding method. Paper analyses and compares these parameters inversion results, which obtain from two kinds of encoding, and choose more suitable one.The paper uses the model with bipolar device (linear measurement and ring measurement) and underground spheroid (stone) which causes abnormal resistivity. Through GA inverse calculation and analysis, the value nearer practice of abnormal resistivity and earth resistivity, abnormal spheroid radius, underground depth and horizontal position can be found.Experimental data is obtained by experimental test bench through field measurement. Experimental test bench data collecting software is LabVIEW which consists of emission electrode, receiving electrode, data acquisition module PMD1608FS and computer. This system has a good man-machine interface; the panel can show collected dada, collected wave and set sampling rate, sampling points and filtering methods, the order times of system.Through the comparing inversion results of two kind coding modes and middle-gradient device in bipolar device model, it concluded that decimal encoding method is more suitable for applications in diode devices (linear measurements and cyclic measurement) parameters inversion of the ground electricity model.更多还原