Response Characteristics Of Three Components Apparent Resistivity In Advance Detection Of Tunnel

Coal plays a fundamental and bottom-saving role in China’s energy system.As the coal mining continuous to deep stage,it faces huge threats to safety mining.Deep disasters that,such as gas,water and rock burst and so on,occurred in the deep strata and coupled with each other,have complex formation mechanism and more difficult to prevent and control,which seriously affects the safety production of coal mines.Safety,intelligent and precise mining of coal mine is the main way to achieve high quality development of coal industry,and mine geological guarantee technology is an important foundation support.As a necessary means of mine geological exploration,basic theory and accurate detection method of geophysical technology need to be further studied.The direct current resistivity method is an important means of advanced detection to water disaster ahead of tunnel driving face,but it currently has many shortcomings in the aspect of observation layout and detection effect.Therefore,it has important significance to research on the advanced detection theory of resistivity method in tunnel.In this paper,based on the traditional resistivity advance detection method,in view of the shortcomings of the existing methods,a three components apparent resistivity observation method is proposed,and the detailed observation flow is given.Based on the fault model of infinite slab in full-space homogeneous media,the three components apparent resistivity formula of full-space tunnel advanced detection is derived.Based on this,numerical calculation and theoretical analysis are used to study the variation relationship between the azimuth angle,dip angle,electrical property,distance and distance of faults in front of tunnel tunneling and the three components apparent resistivity under the condition of uniform surrounding rock,and reveal the three components apparent resistivity response law under the influence of faults in uniform surrounding rock medium.It is determined that fault electrical property is the main key factor of x component apparent resistivity curve type,fault electrical property and orientation are the main key factor of y component apparent resistivity curve type,fault electrical property and dip are the main key factor of z component apparent resistivity curve type.Fault azimuth angle,dip angle,electrical property,distance to point power supply and fault distance together determine the abnormal characteristics of apparent resistivity in three components and the relationship between probe poles.Taking the deep A group coal seam roadway and its bottom-drawing roadway excavation in Huainan mining area as the research background,through the construction of the formation geoelectric model,based on Comsol simulation software,the three components apparent resistivity response characteristics of water-bearing faults ahead of tunnel tunneling under different azimuths and dip angles were studied respectively,reveals the formation electrical characteristics influence on three components of the apparent resistivity,Determine the formation electrical on three components of the apparent resistivity anomaly characteristics curve and has the important influence,direct use of the apparent resistivity curve of three components judgement concealed fault with guide water is difficult,but after ratio method to eliminate the formation background of three components characteristics of apparent resistivity anomaly ratio curve and uniform surrounding rock under the condition of water-bearing fault caused by the three components overall apparent resistivity response characteristic,the abnormal features show that it is necessary to eliminate the stratum background when tunneling the tunnel.Paper studies have shown that with the traditional single advance component of the apparent resistivity observation method,compared with three components apparent resistivity observation method of hydraulic conductivity of concealed geological structure and its spatial distribution of capturing ability has been a sharp increase,enrich the geoelectric information,to the actual detection more advantages,at the same time points out the shortages existing in the research direction and the subsequent work.Figure [33] table [19] reference [85]...