Research On Three-dimensional Measurement Method Of Underground Deformation Based On Capacitance Length Measurement

Geological disaster monitoring is an important part of preventing geological disasters,and underground displacement monitoring technology is an important means of geological disaster monitoring.The existing underground displacement monitoring technology has the problems of low accuracy,difficult installation,and high cost.The three-dimensional measurement technology of underground deformation based on capacitance length measurement proposed by the author realizes the measurement of the size and direction of underground displacement,and can remotely conduct underground deformation monitor.The main contents of this article are:1.Study the existing underground displacement monitoring technology,make a comparative analysis of various technical methods,summarize the advantages and disadvantages of each method,and propose a three-dimensional measurement method of underground deformation based on capacitance measurement.2.The overall structure design and measurement principle of the three-dimensional measurement sensor system for underground deformation are expounded.The principles of mutual inductance,the measurement method of inclination angle and azimuth,the technology of twitch variable capacitor distance measurement.3.Device selection for each measurement module to be implemented in the sensor system,design the overall hardware circuit in combination with the actual situation,and debug the circuit.4.Introduce the experimental operation platform.Compile corresponding lower computer and upper computer programs to realize the automatic control of the stage by the upper computer software and the collection and storage of experimental data.5.The capacitor structure of twitch variable capacitance is designed and installed in the sensor unit,and the fitting curve of the extraction length and voltage of the capacitor core is experimentally calibrated.An integrated chip sensor is used to measure the tilt angle and tilt orientation of the sensor unit.Calibration experiment of mutual inductance voltage displacement under different tilt angles.6.Mathematical models are established based on the data collected by the mutual inductance voltage displacement calibration experiment under different tilt angles.The experimental comparison of the measured displacement values between the sensor units and the true displacement values is used to calculate and analyze the experimental errors.The overall error of the horizontal displacement and vertical displacement of the sensor unit measured in the experiment is within-2mm ? 2mm.The underground deformation three-dimensional measurement sensor designed in this paper can measure the horizontal and vertical displacement between the sensor units,and the measurement of the inclination angle and inclination between the sensor units.Compared with other underground deformation monitoring methods,the measurement range is wider,the accuracy is higher,and the deformation of underground rock and soil bodies can be more comprehensively reflected,which lays the foundation for further research on subsequent underground deformation monitoring technology.