| Radio wave perspective method has the advantages of light operation,fast data coll ection,good detection effect,etc.It is widely used in the exploration of structural abnor mal areas such as coal seam face faults and thin coal areas.In the detection of large and wide coal seams,strong low-resistance false anomalies are generated due to the serious attenuation of electromagnetic wave signals,which causes great interference to the expl oration of small structures on the working face.For this reason,this paper proposes the radio wave source detection of geological abnormalities in coal seam working face and t he same lane detection method for in-plane geological structure exploration.Using theo retical analysis,numerical simulation,and field testing,the basic theory involved in the radio wave source detection and detection method in the same lane is studied.The speci fic content is as follows:First,the thesis is based on the propagation and attenuation characteristics of elect romagnetic waves,using Gpr Max software to analyze strike faults,Perform radio wav e multi-frequency simulation tests on sloping faults and collapsed pillars of terrestrial st ructural anomalies.Numerical simulation results show that in a uniform formation,whe n there is no structural anomaly,the attenuation results of the multi-frequency detection field strength are roughly the same,and the overall trend is exponential.When the struct ural anomaly exists,the multi-frequency detection field strength attenuation becomes sl ower,and the overall field The intensity value is large;the multi-frequency detection cu rves of near-strike faults and inclined faults are quite different,but they are similar to th e multi-frequency detection results of collapse column detection,indicating that the infl uence of electromagnetic wave signal value changes may be related to the reflection dist ance of the receiving point and the abnormal body.The above results verify that it is the oretically feasible to detect geological structures in the same lane by radio wave source i nspection.Secondly,study the propagation characteristics of electromagnetic wave structure anomaly detection in the same lane under ground half-space conditions,and use YDT-88 pit penetrator to select suitable test sites and observation systems to carry out multi-fre quency ground half-space tests.The results of the ground half-space test show that the f ield strength value of the received radio wave source in the same lane from the open gro und to the building suddenly increases through the interface of the two media,indicatin g that the abnormal structure affects the change of the electromagnetic wave signal.It is verified that the radio wave source detection and detection of structural anomalies in th e same lane is feasible under the condition of ground half space.Finally,further study the feasibility of underground radio wave source inspection t o detect geological structure anomalies in the same lane,use the YDT-88 pit penetration instrument,set up a reasonable observation system to conduct downhole actual measure ment tests,and process and analyze the test data through the field strength comparison method.The downhole field test shows that when the radio wave signal passes near the fault,the received field strength value suddenly becomes larger,and the larger the fault,the larger the range of the abnormal change of the field strength value.The results of simulation test,surface half-space test,and downhole field test are c onsistent with each other.Comprehensive analysis shows that it is feasible to detect geo logical structures in the same lane by radio wave source detection,and is sensitive to ne ar-trend and oblique faults;near-trending anomaly detection,which affects the value of electromagnetic wave signal may be related to the distance between the receiving point and the reflection interface of the abnormal body.The accuracy of this requires further r esearch.Figure[35]table[12]reference[100]... |
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