阅读说明：本技术 深埋长隧道不良地质转向勘察的电测深成像方法 (Electric deep imaging method for deep-buried long tunnel unfavorable geological steering investigation ) 是由 周超 金彦 叶辉 刘玉 张佩 张倩 于 2020-12-25 设计创作，主要内容包括：本发明公开了深埋长隧道不良地质转向勘察的电测深成像方法,包括如下步骤：步骤1：将电法仪的多个电极纵向等间距插入待测区域的地面上；步骤2：电法仪的各个电极将感应到的电压信号通过采集站反馈回主机；步骤3：得到电法仪的电极纵向布置位置下方竖向截面不同深度的分布式视电阻率数据；步骤4：将电法仪的多个电极横向等间距插入待测区域的地面上；步骤5：电法仪的各个电极将感应到的电压信号通过采集站反馈回主机；步骤6：得到电法仪的电极横向布置位置下方竖向截面不同深度的分布式视电阻率数据；步骤7：得到不同深度的三维视电阻率数据。本发明能实现地质结构的三维电测深成像,提高探测准确性。(The invention discloses an electrical sounding imaging method for deep-buried long tunnel unfavorable geological steering exploration, which comprises the following steps: step 1: inserting a plurality of electrodes of an electrical method instrument on the ground of a region to be measured at equal intervals in the longitudinal direction; step 2: each electrode of the electrical method instrument feeds back the sensed voltage signal to the host through the acquisition station; and step 3: obtaining distributed apparent resistivity data of different depths of a vertical section below an electrode longitudinal arrangement position of the electrical method instrument; and 4, step 4: transversely inserting a plurality of electrodes of an electrical method instrument into the ground of a region to be detected at equal intervals; and 5: each electrode of the electrical method instrument feeds back the sensed voltage signal to the host through the acquisition station; step 6: obtaining distributed apparent resistivity data of different depths of a vertical section below an electrode transverse arrangement position of the electrical method instrument; and 7: and obtaining three-dimensional apparent resistivity data of different depths. The invention can realize three-dimensional electrical sounding imaging of the geological structure and improve the detection accuracy.)

1. An electrical sounding imaging method for deep-buried long tunnel unfavorable geological steering exploration is characterized by comprising the following steps:

step 1: inserting a plurality of electrodes of an electrical method instrument on the ground of a region to be measured at equal intervals in the longitudinal direction;

step 2: the host sends a signal acquisition command to the acquisition station, the acquisition station supplies power to each electrode of the electrical method instrument, and each electrode of the electrical method instrument feeds back the sensed voltage signal to the host through the acquisition station;

and step 3: the host machine obtains distributed apparent resistivity data of different depths of a vertical section below an electrode longitudinal arrangement position of the electrical method instrument according to the voltage signal acquired by each electrode and the distance between two adjacent electrodes;

and 4, step 4: transversely inserting a plurality of electrodes of the electrical method instrument into the ground of the area to be measured at equal intervals, wherein intersection points exist between the transverse electrode arrangement position and the longitudinal electrode arrangement position in the step 1;

and 5: the host sends a signal acquisition command to the acquisition station, the acquisition station supplies power to each electrode of the electrical method instrument, and each electrode of the electrical method instrument feeds back the sensed voltage signal to the host through the acquisition station;

step 6: the host machine obtains distributed apparent resistivity data of different depths of a vertical section below an electrode transverse arrangement position of the electrical method instrument according to the voltage signal acquired by each electrode and the distance between two adjacent electrodes;

and 7: and the host machine combines the distributed apparent resistivity data with different depths of the vertical cross section below the electrode longitudinal arrangement position and the distributed apparent resistivity data with different depths of the vertical cross section below the electrode transverse arrangement position according to the coordinates of each electrode to form three-dimensional apparent resistivity data with different depths.

2. The electrical deep imaging method for poor geological steering exploration of the deep-buried long tunnel according to claim 1, wherein the electrical deep imaging method comprises the following steps: and 7, further comprising a step 8: longitudinally arranging electrodes of an electrical method instrument, transversely translating the longitudinally arranged electrodes for a preset distance, and then inserting the longitudinally arranged electrodes into the ground to obtain distributed apparent resistivity data of different depths below the longitudinally arranged positions of the other group of electrodes;

and step 9: the method comprises the steps that transversely arranged electrodes of an electrical method instrument are longitudinally translated for a preset distance and then are inserted into the ground, a plurality of intersection points exist between the transversely arranged electrodes and the longitudinally arranged electrodes, and a host machine combines distributed apparent resistivity data of different depths of vertical sections below the longitudinally arranged electrodes of each group and distributed apparent resistivity data of different depths of vertical sections below the transversely arranged electrodes of each group according to coordinates of the electrodes to form three-dimensional apparent resistivity data of different depths of an area to be measured.

3. The electrical deep imaging method for poor geological steering exploration of the deep-buried long tunnel according to claim 2, characterized in that: step 10 is also included after step 9: and combining the coordinate positions of the electrodes which are transversely and longitudinally arranged and correspond to the electrodes of the electrical method instrument with the three-dimensional apparent resistivity data of the region to be measured at different depths to form electrical depth three-dimensional imaging.

Technical Field

The invention relates to the technical field of tunnel geological detection equipment, in particular to an electrical sounding imaging method for steering exploration of poor geology of a deep-buried long tunnel.

Background

The high-density electrical method is used for tunnel geological disaster detection, the high-density electrical method section is arranged on the outer earth surface of the tunnel, imaging of poor geology such as tunnel underground water and faults is achieved, potential risk sections of mud burst and water burst and collapse and roof fall disasters can be judged macroscopically, and good effects are achieved.

At present, when a new round of capital construction peak comes, the buried depth of a road tunnel and a railway tunnel is larger and larger, and when the existing electric method instrument is used for detecting under a long-distance complex geological condition, only 2-dimensional imaging can be carried out, so that the accuracy of a detection result is not high. Two-dimensional imaging adopts a plane imaging, for example, a survey line is an X axis, a measurement depth is a Z axis, apparent resistivity ρ is (X, Z), and the environment is complicated in field work, and has 3 main disadvantages: 1. the interference is many, non-target body geological noise, natural electromagnetic noise, anthropogenic interference (civil electricity sharing artificial buried object and the like) 2, the signal is weak, the power of a field working power supply is limited, the strength of a measured signal is limited by 3, the dynamic range is large, the distance between a receiving and a transmitting electrode is greatly changed along with the change of a measuring point position and an electrode in the measurement, the change of the measured signal is greatly changed, each signal with different magnitudes is accurately measured once or one surface, and the error of the result is very large.

Disclosure of Invention

The invention aims to provide an electrical sounding imaging method for steering exploration of poor geology of a deep-buried long tunnel.

In order to realize the purpose, the invention discloses an electrical deep imaging method for poor geological steering exploration of a deep-buried long tunnel, which comprises the following steps:

step 1: inserting a plurality of electrodes of an electrical method instrument on the ground of a region to be measured at equal intervals in the longitudinal direction;

step 2: the host sends a signal acquisition command to the acquisition station, the acquisition station supplies power to each electrode of the electrical method instrument, and each electrode of the electrical method instrument feeds back the sensed voltage signal to the host through the acquisition station;

and step 3: the host machine obtains distributed apparent resistivity data of different depths of a vertical section below an electrode longitudinal arrangement position of the electrical method instrument according to the voltage signal acquired by each electrode and the distance between two adjacent electrodes;

and 4, step 4: transversely inserting a plurality of electrodes of the electrical method instrument into the ground of the area to be measured at equal intervals, wherein intersection points exist between the transverse electrode arrangement position and the longitudinal electrode arrangement position in the step 1;

and 5: the host sends a signal acquisition command to the acquisition station, the acquisition station supplies power to each electrode of the electrical method instrument, and each electrode of the electrical method instrument feeds back the sensed voltage signal to the host through the acquisition station;

step 6: the host machine obtains distributed apparent resistivity data of different depths of a vertical section below an electrode transverse arrangement position of the electrical method instrument according to the voltage signal acquired by each electrode and the distance between two adjacent electrodes;

and 7: and the host machine combines the distributed apparent resistivity data with different depths of the vertical cross section below the electrode longitudinal arrangement position and the distributed apparent resistivity data with different depths of the vertical cross section below the electrode transverse arrangement position according to the coordinates of each electrode to form three-dimensional apparent resistivity data with different depths.

The invention has the beneficial effects that:

according to the method, the three-dimensional electrical sounding imaging of the geological structure of the region to be detected is obtained, and compared with the traditional two-dimensional imaging, the detection accuracy is improved. The method is simple, additional equipment is not needed, and the detection cost is low.

The three-dimensional imaging of the invention uses data of a plurality of bit planes and vertical intersecting bit planes for imaging, can reduce the influence in the aspects of 3 defects, and can obtain obvious denoising effect through multiple point position superposition 1; 2. the signal superposition processing of different bit planes is carried out for multiple times, so that the signal intensity is increased, and the final imaging result is more accurate; 3. the X-axis and Y-axis two-dimensional imaging points use different electrode output modes (the electrode arrangement directions are different, and the electrode output modes are arranged along the X-axis and the Y-axis), and after intersecting and superposing imaging, the error of the three-dimensional imaging result can be obviously improved.

Drawings

FIG. 1 is a schematic diagram of the three-dimensional electrical depth imaging of the present invention;

Detailed Description

The invention is described in further detail below with reference to the following figures and specific examples:

the invention discloses an electrical deep imaging method for steering exploration of unfavorable geology of a deep-buried long tunnel, which comprises the following steps:

step 1: inserting a plurality of electrodes of an electrical method instrument into the ground of an area to be measured at equal intervals (5-10 meters) in the longitudinal direction;

step 2: the host sends a signal acquisition command to the acquisition station, the acquisition station supplies power to each electrode of the electrical method instrument, and each electrode of the electrical method instrument feeds back the sensed voltage signal to the host through the acquisition station;

and step 3: the host machine obtains distributed apparent resistivity data of different depths of a vertical section below an electrode longitudinal arrangement position of the electrical method instrument according to the voltage signal acquired by each electrode and the distance between two adjacent electrodes;

and 4, step 4: transversely inserting a plurality of electrodes of the electrical method instrument into the ground of the area to be measured at equal intervals, wherein intersection points exist between the transverse electrode arrangement position and the longitudinal electrode arrangement position in the step 1;

and 5: the host sends a signal acquisition command to the acquisition station, the acquisition station supplies power to each electrode of the electrical method instrument, and each electrode of the electrical method instrument feeds back the sensed voltage signal to the host through the acquisition station;

step 6: the host machine obtains distributed apparent resistivity data of different depths of a vertical section below an electrode transverse arrangement position of the electrical method instrument according to the voltage signal acquired by each electrode and the distance between two adjacent electrodes;

the apparent resistivity basic calculation formula is as follows:

k is the electrode assembly coefficient; i is a measuring current; delta U_MNIs a potential difference;

and 7: the host machine combines the distributed apparent resistivity data with different depths of the vertical cross section below the electrode longitudinal arrangement position and the distributed apparent resistivity data with different depths of the vertical cross section below the electrode transverse arrangement position according to the coordinates of each electrode to form three-dimensional apparent resistivity data with different depths;

and 8: longitudinally arranging electrodes of an electrical method instrument, transversely translating the longitudinally arranged electrodes for a preset distance (5-10 m), and then inserting the longitudinally arranged electrodes into the ground to obtain distributed apparent resistivity data of different depths below the longitudinally arranged positions of the other group of electrodes;

and step 9: the method comprises the following steps that transversely arranged electrodes of an electrical method instrument are longitudinally translated for a preset distance (5-10 m) and then inserted into the ground, a plurality of groups of transversely arranged electrodes and a plurality of groups of longitudinally arranged electrodes are provided with a plurality of intersection points, and a host machine combines distributed apparent resistivity data of different depths of vertical sections below the longitudinally arranged positions of all groups of electrodes and distributed apparent resistivity data of different depths of vertical sections below the transversely arranged positions of all groups of electrodes according to coordinates of all electrodes to form three-dimensional apparent resistivity data of different depths of a region to be detected;

step 10: the coordinate positions of the electrodes which are transversely and longitudinally arranged and correspond to the electrodes of the electrical method instrument are combined with three-dimensional apparent resistivity data of different depths of a region to be measured to form electrical depth three-dimensional imaging, as shown in figure 1.

Among the above-mentioned technical scheme, the collection station begins to supply power respectively for the electrode on the cable cluster through inside electrode converter, and the voltage power supply signal that the electrode also can will gather simultaneously sends back for the collection station through the cable, is unified again by the collection station at last and transmits back the host computer.

In the technical scheme, a host of the electrical method instrument supports wifi and usb modes to be connected with an acquisition station, the acquisition station is controlled to acquire data, and a constant voltage mode (200V, 400V, 800V and 1200V are selectable) and a variable voltage mode (the deeper the detection is, the higher the voltage) can be selected for acquiring power supply voltage; supporting common high-density electrical devices such as wenna, schlongberg, unilateral three-level, two-level, etc.; supporting long-array continuous rolling measurement; the acquisition can be suspended, stopped and rolled back at any time, and the acquired data can be stored in real time. Every cable all has 1 extension interface and a power supply interface of being equipped with, and the extension interface can prolong detection length, and power supply interface can supply when system power output is not enough, and the current deep buried long distance detection work of perfect solution exports not enough problem in the middle of.

According to the invention, the supplementary power supply is added at the tail part of each cable, the output power of the electrode can be increased, the acquisition depth can be improved, the acquired voltage data can be more accurate, meanwhile, the function of the cable integrating the electrode box is obviously improved in the aspects of integration, stability and waterproofness, in addition, the three-dimensional imaging is more convenient to process and explain compared with two-dimensional imaging, and the three-dimensional imaging has strong stereoscopic impression and clearer structural relationship.

Details not described in this specification are within the skill of the art that are well known to those skilled in the art.