CN110700846B

CN110700846B - Shield constructs machine based on geology is surveyed in advance

Info

Publication number: CN110700846B
Application number: CN201911075570.6A
Authority: CN
Inventors: 付春青; 钱新; 李斌; 刘冬; 陈金刚; 李黎
Original assignee: Beijing Uni Construction Group Co Ltd
Current assignee: Beijing Uni Construction Group Co Ltd
Priority date: 2019-11-05
Filing date: 2019-11-05
Publication date: 2021-03-16
Anticipated expiration: 2039-11-05
Also published as: CN113107507B; CN110700846A; CN113107507A; CN113107506B; CN113107506A

Abstract

The invention relates to a shield machine based on geological advanced detection, which at least comprises a shield machine main body and an advanced detection device arranged on the shield machine main body, wherein the advanced detection device at least comprises a control module and a control module, wherein a detection signal is transmitted to a coil group to carry out geological advanced detection, so that the control module can realize joint inversion analysis of a geological three-dimensional model by receiving measurement data fed back by the coil group, and the control module is also configured to: transmitting a first detection signal for direct current detection through the transmitting module group when the shield machine main body is in a tunneling working state; transmitting a second detection signal for transient electromagnetic detection and/or a third detection signal for nuclear magnetic resonance detection through the transmitting module group when the shield machine main body is in a state of stopping working; the first detection signal, the second detection signal and/or the third detection signal can be detected by the coil assembly in a current field and an electromagnetic field.

Description

Shield constructs machine based on geology is surveyed in advance

Technical Field

The invention relates to the technical field of tunnel shields, in particular to a shield machine based on geological advanced detection.

Background

The shield machine is a totally-enclosed tunnel boring machine, belongs to mechanical equipment for excavating tunnels and other channels, and is a construction machine which can support the pressure of a stratum and can also tunnel in the stratum. The shield machine is used for tunnel construction, and has the characteristics of high automation degree, labor saving, high construction speed, one-step tunneling, no influence of weather, controllable ground settlement during excavation, reduction of influence on ground buildings, no influence on water traffic during underwater excavation and the like. However, the subway shield construction is mostly in a dense section, the surrounding environment is complex, the operation of traversing various buildings, railways, rivers, bridges and the like is increasingly frequent, moreover, because of more construction nodes, different construction units, different management concepts and levels, the construction of subway engineering and the future operation management are left with non-negligible problems and potential safety hazards, safety accidents caused by subway construction seriously affect the life and property safety of people, cause different social benefits of construction and operation, and have a remarkable influence.

For example, Beijing subway is one of the signs of urban traffic in China, and has developed nearly 55 years since the construction of subway in 1965, the development scale is large, the development speed is high, and the construction technology level makes revolutionary breakthrough. The Beijing subway No. 12 line is a three-loop line and is an encryption line in the Beijing north, wherein the three-way bridge station is positioned at the high-speed east side of an airport. The design trend of the west dam river station-three-way bridge station is as follows: laying along the north-tricyclic east road to the east south, bypassing the three-component west bridge from two sides, adjusting the line trend and reducing the line distance to the front left line of the airport expressway, turning to the east side of the airport expressway after passing through the three-component bridge ramp bridge, and laying to the west dam river station. The interval has a complex geological structure and a high diving water level, so that the shield machine can frequently encounter multiple complex geological structure characteristics such as a composite stratum in the crossing process, if the geological conditions in front of the shield tunneling working face and in the depth direction cannot be accurately judged, the construction progress can be influenced, and more serious settlement can be caused in partial intervals, so that the safety of roads, nearby buildings and the lives of people is seriously threatened. The safety benefits of shield construction of Beijing as the national political culture center and the main cities for developing and constructing subways are particularly sensitive and prominent, so that the reinforcing of the shield construction risk management and control and the safety control technology research of the Beijing subways has very important significance and is very urgent.

Geological exploration can be likened to a physician's "stethoscope" with knowledge of geological features at different depths. Geological exploration has a long development history and accumulates a great deal of knowledge and experience. For example, Sattle et al, 1992, used a seismic exploration technique within a pilot tunnel in Switzerland by using signal receivers mounted on the tunnel walls to receive seismic wave energy generated by small shots to predict the geology ahead of the tunnel face.

For example, chinese patent publication No. CN104863602B discloses an advanced forecasting method for soil shield tunnel construction diseases. The method is characterized in that an advanced detection device is arranged in front of the shield machine, the advanced probe can be used for detecting the lateral resistance, the end resistance and the pore water pressure of a soil layer so as to determine the property of the soil layer, then the result is transmitted to a shield construction control center to form a three-dimensional model of soil layer distribution and property, and a three-dimensional model of soil layer distribution and property prediction which is continuously corrected in a larger range is automatically generated, so that the engineering property of the soil body in front is judged, a construction scheme is revised in time, safety measures are taken, the engineering cost is saved, the construction quality is ensured, and major safety accidents. The method can predict the construction environment, optimize the construction scheme, adopt safety measures, is safe, convenient and material-saving, can be suitable for soil layers with different properties, and is an accurate and economic advanced disease prediction method for the soil shield tunnel construction in the shield construction.

For example, chinese patent publication No. CN110206548A discloses a multifunctional supporting device, a heading face geological advanced detection system, and a heading machine, where the heading face geological advanced detection system includes: a multifunctional supporting device and a geological detection device; the multifunctional supporting device comprises a fixed arm, a telescopic arm connected with the fixed arm and a supporting oil cylinder for providing supporting power for the telescopic arm, wherein the working end of the telescopic arm is connected with equipment to be supported or a surface to be supported; the fixed arm is hinged with a cutting arm of the heading machine, and the geological detection device is arranged at the working end of the telescopic arm. The invention fixedly supports the geological advanced detection system of the heading face by utilizing the multifunctional supporting device fixed with the cutting arm of the heading machine, does not need special vehicles or manual carrying, ensures the geological detection efficiency and the detection safety, solves the problem of site limitation, meets the requirement of real-time property, has strong applicability, effectively reduces the safety accidents of heading operation, improves the construction efficiency and the construction quality, and has stronger engineering application prospect.

For example, chinese patent publication No. CN105068128B discloses a three-dimensional induced polarization advanced prediction system and a detection method carried by a soil pressure balance shield, in which a thrust electrode system carried on a cutter head is used to penetrate a needle electrode into a soil body for power supply and collection, thereby overcoming the difficulty that the soil pressure balance shield has no detection space; the shield electrode is utilized to lead the detection current to be distributed forwards and the slurry spraying equipment on the cutter head sprays high-resistance slurry injecting materials to the cutter head and the soil body around the shield, so that the difficulty of electromagnetic interference and the difficulty of leading out the current by using the shield as a good conductor are overcome; the difficulty of short detection time is overcome by using full-process automatic control, multipath parallel acquisition and rapid inversion means. The method utilizes the geologic body resistivity difference to realize the detection of spherical weathered bodies, soft and hard layered strata, front full-section hard rocks, pebble layers and sludge layers; and the detection of the water content of the water-rich layer is realized by utilizing the induced polarization half-decay.

For example, chinese patent publication No. CN105891890B discloses a shield-carried non-contact frequency domain electrical method real-time advanced detection system and method, in which a non-contact electrode is installed on a cutter head of a shield machine, and the system transmits and receives current by using capacitive coupling, and is connected to a host machine through a multi-way rotary joint, so as to invert and interpret measured data in real time, and transmit the prediction result to a shield machine control system, so as to provide technical support for the safe construction of the shield machine; a non-contact electrode is arranged on the shield cutter head, so that the problem of difficult coupling of the traditional contact electrode is avoided; meanwhile, the shield machine does not need to be stopped in the shield tunneling process, the real-time advanced detection of the front geology of the tunnel face can be realized, the requirement for rapidity of shield construction is met, the efficiency of the advanced geological detection of the shield machine is greatly improved, the interference of metal objects behind can be effectively avoided only by installing an electrode system on the cutter head, the advanced detection capability of the front is improved, and more importantly, the problem that the space between the cutter head and the tunnel face is very narrow is solved.

For example, document [1] zhao shui, zhangshiang, likakai, et al. No.536(02) 117 and 120 disclose a shield tunneling machine tunneling roadway advanced detection real-time monitoring system, which comprises hardware, an excitation mode, a measurement mode and the like, and a three-dimensional resistance tomography method is used for obtaining resistivity distribution at each point in a measurement area. The advanced detection real-time monitoring system for the coal mine tunnel excavated by the shield machine takes a cutter head of the shield machine as an excitation and measurement electrode for data acquisition, and utilizes a resistance tomography algorithm to perform inversion analysis on the measured data to find an abnormal body in front of the shield machine in construction. Basic principles of electrical resistance tomography: the conductivity difference of different substances is utilized, the distribution of the sensitivity in the measuring region is obtained through the distribution of the resistivity in the measuring region, and then the image reconstruction can be implemented by utilizing a tomography algorithm.

However, the advanced detection technology disclosed in the above documents is greatly influenced by the rear and the side wall of the current roadway and has weak sensitivity to an abnormal body in front of the driving face, or has low resolution due to the influence of a volume effect, so that it is difficult to accurately distinguish an actual electrical interface, and a detection blind area exists due to the influence of turn-off time. In addition, due to the influence of the full space effect, the front and the rear of the tunneling working face are abnormally mixed together and are difficult to separate.

The geological radar detection method is the engineering geophysical method with the highest resolution at present and is derived from the aerospace sounding radar technology in Europe and America. Although the use of radar principles for ground exploration was proposed by GLeimbach and h.l6wy in 1910 germany, the practical application range of ground penetrating radar was expanded after the last 70 th century. Geological radar is widely adopted in engineering quality detection site investigation, and is also used for tunnel advanced prediction work in recent years. The method can find out the change of the stratum in front of the face, and has higher identification capability for fracture zones, particularly water-containing zones and fracture zones. In deep-buried tunnels, water-rich stratums and karst cave development areas, geological radar is a good forecasting means. However, the current detection distance of the geological radar is short, about within 20-30m, the forecasting of the long-distance tunnel can be only carried out in a segmented mode, and meanwhile, the radar record is easily interfered by in-hole electrical equipment.

With the deep development of underground engineering construction, the depth (20-30m) detected by the traditional geological radar can not meet the engineering requirements, and the exploration requirements on the quality and the effect of geological detection, particularly on underground special geological conditions and cavity and hydrological conditions, are higher and higher. In summary, in order to solve the above technical problems, the invention provides a shield machine based on advanced detection, which realizes remote accurate advanced detection on the basis of short-distance accurate exploration of a geological structure in front of the shield machine, and establishes a three-dimensional model of the geological structure, thereby realizing inversion settlement analysis of the geological three-dimensional model.

Furthermore, on the one hand, due to the differences in understanding to the person skilled in the art; on the other hand, since the inventor has studied a lot of documents and patents when making the present invention, but the space is not limited to the details and contents listed in the above, however, the present invention is by no means free of the features of the prior art, but the present invention has been provided with all the features of the prior art, and the applicant reserves the right to increase the related prior art in the background.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a shield machine based on geological advanced detection, which at least comprises a shield machine main body and an advanced detection device arranged on the shield machine main body. The advanced detection device at least comprises a control module, a transmitting module group and a coil group. The control module is configured to transmit a detection signal to the coil assembly through the transmitting module assembly for geological advanced detection, so that the control module can realize joint inversion analysis of a geological three-dimensional model by receiving measurement data fed back by the coil assembly. The control module is further configured to: transmitting a first detection signal for direct current detection through the transmitting module group when the shield machine main body is in a tunneling working state; and transmitting a second detection signal for transient electromagnetic detection and/or a third detection signal for nuclear magnetic resonance detection through the transmitting module group when the shield machine main body is in a state of stopping working. The first detection signal, the second detection signal and/or the third detection signal can be detected by the coil assembly in a current field and an electromagnetic field. In the process of arranging the advanced detection device on the main body of the shield machine for advanced detection, detection methods adopted by different detection technologies have different limitations, and in a plurality of natural irreparable contradictory subjects consisting of detection distance, detection accuracy, detection speed, construction cost and construction speed, aiming at advanced detection combined modes under different construction grading conditions, the advantages complementation and interference suppression of various detection technologies are realized, and long-distance detection and short-distance detection are combined, so that the detection precision and the detection distance can be improved, but in the combined mode of a plurality of advanced detection technologies, the problems of arrangement space and interference related to the emission and the reception of detection signals with different physical properties in the combined mode are the key of the combination of different advanced detection technologies and the high-efficiency tunneling and crossing of the shield machine, for example, the combined detection mode of a direct current method and a transient electromagnetic method is adopted, in the direct current method, an electrode is in contact with a tunnel face to perform detection through an excitation current field, and a transient electromagnetic method performs detection through a coil excitation electromagnetic field in a certain space away from the tunnel face, but in a combined detection mode of the electrode and the coil, the electrode and the coil are respectively configured to realize advanced detection, but complex configuration steps seriously restrict the detection efficiency and the crossing speed of a shield machine; moreover, although the electrode used in the direct current method and the coil used for separately exciting the current field and the electromagnetic field can be respectively arranged on the cutter head or the head of the shield tunneling machine, the electrode used in the direct current method rotates along with the cutter head during operation, a certain excitation effect can be generated on the nearby coil, the excited electromagnetic field can generate interference on the current field, and the nearby metal electrode can also generate interference on the electromagnetic field during the excitation process of the coil, so that the distance and the accuracy of advanced detection are influenced. In the invention, due to the dynamic configuration of the conductive entity and the conductive line segment of the coil set, the coil set can realize the conversion of the excitation current field to the excitation electromagnetic field, the combined mode of the advanced detection technologies for detecting different physical properties can realize continuous advanced detection and seamless switching of different advanced detection technologies under two working states of tunneling and stopping of the shield machine without complex reconfiguration and large configuration space, and aiming at the problem that different advanced detection technologies before and after switching interfere with each other, the conversion process between the current field and the electromagnetic field of the coil group can realize conversion gain and direction focusing, and the method is particularly suitable for being combined with excavation-following advanced detection and static advanced detection in the process that the shield machine passes through the underground mechanism, and realizing long-distance accurate detection of the bad geologic bodies containing water bodies, cavities, faults and the like.

According to a preferred embodiment, the coil set comprises at least a transmitting coil and a receiving coil. The transmitting coil at least comprises a plurality of conductive entities arranged on a cutter head of the shield tunneling machine main body and at least one conductive line segment positioned between the cutter head and/or the shield tunneling machine main body and the cutter head. At least two of the conductive entities can form a first detection coil with a gap and the gap can be in contact with the conductive line segment such that the at least two conductive entities form a closed loop. The first detection coil is configured to receive the first detection signal transmitted by the transmission module group. Under the rotatory state of blade disc first detection coil with the face contact in shield constructs main part the place ahead is in order to transmit first detection signal and response first detection signal's change, thereby with first detection signal's change transmission extremely control module.

According to a preferred embodiment, the control module can be configured to drive the conductive wire segment into contact with the gaps of the plurality of first detection coils such that the plurality of first detection coils and the conductive wire segment can form a second detection coil of a closed loop. The second detection coil is configured to receive the second detection signal and/or the third detection signal transmitted by the transmission module group to radiate the second detection signal and/or the third detection signal in a state where the shield machine body is stopped to detect a geological structure. And the receiving coil and the receiving module group arranged corresponding to the receiving coil receive response signals returned by the second detection signals and/or the third detection signals. The receiving module group is configured to transmit the response signal to the control module.

According to a preferred embodiment, at least two first detection coils are circumferentially spaced apart from the center of the cutter head. At least one of the conductive line segments is located between two of the first detection coils. The blade disc is provided with the installation first installation department and the installation of first detection coil conductive line segment and can follow the axial displacement of blade disc is so that conductive line segment with the second installation department of conductive entity contact and/or be provided with between blade disc and the shield structure machine main part and be used for the installation conductive line segment just can follow the axial displacement's of blade disc third installation department. The third installation part is arranged in a mode of surrounding the axial direction of the cutter head. The third mounting portion can carry at least one turn of auxiliary coils in a manner of being distributed in multiple layers along the axial direction of the shield machine body. The auxiliary coil is connectable at least with the conductive line segment and the first detection coil, respectively, to form a second detection coil having a plurality of turns.

According to a preferred embodiment, the first detection coils are configured to be spaced from each other in a direction from the center of the cutter head and extend to the edge of the cutter head. The plurality of first sending detection coils can form an in-line array passing through the center of the cutter head, so that a measuring area of the tunnel face in front of the shield tunneling machine body can be completely covered under the rotating state of the cutter head.

According to a preferred embodiment, the second mounting portions are arranged in a manner so as to be distributed in multiple layers in the axial direction of the cutter head. Under the condition that the first detection coils are symmetrical by taking the center of the cutterhead as a center, the first detection coils can be in contact with the conductive line segment to form at least two polygonal closed-loop second detection coils which are spaced from each other along the axial direction of the cutterhead. The closed surfaces formed by the second detection coils of the at least two polygonal closed loops are at least partially overlapped with each other.

According to a preferred embodiment, the advanced detection device further comprises a detection gating module group respectively connected with the control module, the transmitting module group and the coil group. Under the condition that the control module transmits a first detection signal for direct current detection through a first transmitting module in the transmitting module group, the detecting gating module group is configured to: and controlling the conduction of the first transmitting module and the plurality of first detection coils based on a first enabling signal generated by the control module relative to the first detection signal. The detection gating module group sequentially connects two first detection coils which are closest and/or farthest to each other to the positive pole and the negative pole of the first transmission module respectively. Under the condition that any two first detection coils are respectively connected to the positive electrode and the negative electrode of the first transmitting module, the detection gating module group transmits a first measurement signal for controlling the measurement sequence to the receiving module group.

According to a preferred embodiment, the set of receiving modules comprises at least a first receiving unit connected with the first detection coil and a second receiving unit connected with the receiving coil to form a closed loop. The first receiving unit is configured to sequentially measure an electrical signal between a plurality of two first detection coils that are closest and/or farthest to each other, which are not accessed to the first transmission module, based on the first measurement signal, and transmit the electrical signal to the control module. The second receiving unit is located in the center of the second detection coil; or a plurality of second receiving units are symmetrically distributed on the tunnel face and/or the side wall with the center of the second detection coil.

According to a preferred embodiment, in case the control module transmits a second detection signal for transient electromagnetic detection through a second transmission module within the set of transmission modules, the set of detection gating modules is configured to: based on the control module is relative the second enable signal drive that the second detected signal generated the second installation department and/or third installation department are followed the axial displacement of blade disc makes a plurality ofly conducting wire section and a plurality of the breach contact of first detecting coil forms by the first detecting coil of closed loop and the conducting wire constitutes the second detecting coil of closed loop. The detection gating module group conducts the second transmitting module and the second detection coil to radiate a second detection signal. Or under the condition that the control module transmits a third detection signal for nuclear magnetic resonance detection through a third transmitting module in the transmitting module group, the detecting gating module group is configured to: and driving the second installation part and/or the third installation part to move axially along the cutter head based on a third enabling signal generated by the control module relative to the third detection signal, so that the auxiliary coil is in contact with a plurality of conductive line segments and a plurality of conductive line segments are in contact with a plurality of gaps of the first detection coil to form a first detection coil of a closed loop. Whereby the first detection coil, the electrically conductive wire and the auxiliary coil can constitute a multi-turn second detection coil of a closed loop. The detection gating module group conducts the third transmitting module and the second detection coil to radiate a third detection signal.

The invention also provides a geological advanced detection method, which comprises the step of carrying out geological advanced detection by adopting the shield tunneling machine based on geological advanced detection.

Drawings

FIG. 1 is a simplified block diagram of a preferred embodiment of the lead detection assembly of the present invention;

FIG. 2 is a simplified schematic diagram of a preferred embodiment of the shield tunneling machine of the present invention for advanced detection;

FIG. 3 is a schematic view of a preferred arrangement of the first and second mounting portions of the invention;

FIG. 4 is a schematic diagram of a preferred configuration of the first detection coil of the present invention;

FIG. 5 is a schematic view of a preferred sectional configuration of the impeller of the present invention;

FIG. 6 is a schematic view of another preferred sectional configuration of the impeller of the present invention;

FIG. 7 is a schematic diagram of a preferred construction of a second detection coil of the present invention;

FIG. 8 is a schematic diagram of a preferred measurement of the first detection coil of the present invention;

FIG. 9 is a simplified schematic diagram of another preferred embodiment of the shield tunneling machine of the present invention for advanced detection; and

fig. 10 is a schematic view of a preferred measurement of the second detection coil of the present invention.

List of reference numerals

100: the shield machine main body 200: advanced detection device

300: notch 400: auxiliary coil

500: the palm surface 600: conducting wire

110: third mounting portion 120: cutter head

210: the control module 220: transmitting module group

230: the receiving module group 240: detection gating module group

250: coil group 121: first mounting part

122: second mounting portion 221: first transmitting module

222: the second transmitting module 223: third transmitting module

231: the first receiving unit 232: second receiving unit

251: the transmitting coil 252: receiving coil

253: first detection coil 254: second detection coil

2511: conductive entity 2512: conducting wire segment

Detailed Description

The following detailed description is made with reference to fig. 1 to 10.

Example 1

The embodiment discloses a shield machine based on geological advanced detection, which at least comprises a shield machine main body 100 and an advanced detection device 200 arranged on the shield machine main body 100. The lead detection device 200 includes at least a control module 210, a transmitting module set 220, and a coil set 250. The control module 210 is configured to transmit the detection signals to the coil assembly 250 through the transmitting module assembly 220 for geological advanced detection, so that the control module 210 can receive the measurement data fed back by the coil assembly 250 to realize joint inversion analysis of the geological three-dimensional model. Preferably, the joint inversion analysis may be to establish an objective function for response characteristics of the underlying layer and time delay and observation data of different detection methods by using different detection methods. And selecting an iterative algorithm corresponding to the sensitivity and resolution of the selected detection method based on the target function to obtain a corresponding iterative equation, wherein for example, the direct current method has higher resolution capability on a high-resistance layer, and the instantaneous electromagnetic method is sensitive to the reaction of a low-resistance layer, so that the damping least square method can be selected to obtain the iterative equation. Preferably, after the iterative equation is obtained, the model correction amount can be calculated according to different initial models, so that an iterative solution is obtained, and iterative calculation is performed in a mode that the iterative solution is used as an initial value of the next iteration. Preferably, the book output model can select a low-resistance target layer model, for example, the second layer and the fourth layer as the low-resistance target layer.

Preferably, the control module 210 is further configured to: when the shield tunneling machine main body 100 is in a tunneling working state, a first detection signal for direct current detection is transmitted through the transmission module group 220; and transmitting a second detection signal for transient electromagnetic detection and/or a third detection signal for nuclear magnetic resonance detection through the transmission module group 220 in a state that the shield machine main body 100 is stopped. Preferably, the first detection signal can be detected by a direct current method, such as a direct current three-stage method, a direct current focusing method and an excitation method. The basic principle of the direct current electric method is that current is introduced into surrounding rocks of a face to be detected, the integrity and the water content of the front rock are forecasted by measuring the resistivity of the rock or the change of parameters PEE (percent frequency effect) related to the electric energy storage capacity, the results are continuously obtained along with the tunneling, the curve or the resistivity curve of PFE in the front of the face is obtained by timely processing, and the properties and the water content of the front rock are forecasted and forecasted by deducting from the curve. The method is characterized in that the cutter head 120 and/or the cutter of the shield tunneling machine can be used as carriers of the electrodes. As shown in fig. 2, the cutterhead 120 and/or the electrode on the cutter of the shield machine are in contact with the tunnel face 500 in front of the shield machine main body 100, and current can be continuously introduced to continuously detect when the shield machine is in operation, i.e. the cutterhead 120 and/or the cutter are rotating. The specific implementation process is as follows: at the boundary of the field being measured, i.e. the tunnel face 500, a suitable excitation current is introduced, and if the resistivity inside it changes, the voltage value at the measured boundary changes accordingly. I.e. by applying a suitable excitation signal, the response process of the field is measured. The voltage value obtained by the resistance tomography can reflect the response results of different media in the measuring region, and finally the internal medium composition is analyzed and reduced through a corresponding algorithm. The shield machine is used as a carrier, and the resistivity and/or PEE tomography technology is combined, so that advanced detection is realized.

Preferably, the second detection signal can be detected by a transient electromagnetic method. The transient electromagnetic method belongs to a time domain electromagnetic method, and mainly sends a primary pulse electromagnetic field to a detection direction through an ungrounded loop or a grounding electrode, under the excitation of the primary field, the induction current is generated in a geological structure conductor, and the secondary magnetic field generated by the induction current does not disappear immediately along with the disappearance of the primary field during the intermission period of the primary pulse magnetic field, so that the secondary magnetic field is observed by using a coil or the grounding electrode, the change relation between the secondary magnetic field and practice is researched, the electrical distribution and the space form of an underground geologic body can be further determined. The transient electromagnetic method has the advantages that: the method is sensitive to low resistivity reaction and has more advantages in the aspect of rock stratum water-rich detection; the advanced detection distance is large, and the detection direction directivity is good; convenient and fast construction, low labor intensity and the like. The disadvantages are: due to the influence of a volume effect, the resolution ratio is low, the actual electrical interface is difficult to accurately distinguish, and meanwhile, due to the influence of turn-off time and the like, a detection blind area exists; due to the influence of the full space effect, the front and the rear of the tunneling working face are mixed together abnormally and are difficult to separate. In addition, although the transient electromagnetic method can define the position of the low-resistance abnormality, the method cannot directly indicate whether the low-resistance abnormality is caused by the water body.

Preferably, the third detection signal may be detected using nuclear magnetic resonance. The operating principle of nuclear magnetic resonance is similar to that of transient electromagnetic, wherein the transient electromagnetic method adopts step electromagnetic pulse excitation to measure the secondary attenuation field generated by underground medium. However, the nmr method is a geophysical method for directly finding water, and emits an alternating current magnetic field having larmor frequency in a coil to generate an alternating electromagnetic field propagating forward, so that a water-containing body in front of the tunnel face 500 is excited, and the spin magnetic moment of a hydrogen nucleus deviates from the original geomagnetic field by a certain angle. Then the current in the exciting coil is turned off, the magnetic moment of the excited atomic nucleus returns to the original direction of the earth magnetic field, and a nuclear magnetic resonance response signal is released in the process. The signal is picked up by a receiving coil arranged in front of the tunnel face, so that the aim of detecting various disaster water bodies is fulfilled, as shown in fig. 9. Preferably, when other geophysical methods are used for water exploration, whether the structure contains water or not is deduced by observing changes of certain geophysical parameters caused by the water containing of the geological structure, and the method belongs to an indirect water exploration method and is not used for directly exploring water. For example, when water is found by a direct current method, a potential water-containing position is deduced by delineating a region with low resistivity according to the characteristic that the resistivity of a subsurface structure is reduced after water is contained. The nuclear magnetic resonance method is directly aimed at water molecules, so that a nuclear magnetic resonance response signal can be generated only when water exists, and no signal can be generated when water does not exist.

Preferably, the first detection signal, the second detection signal and/or the third detection signal are each detectable by the coil assembly 250 by means of a current field and an electromagnetic field. Preferably, in the process of arranging the advanced detection device on the main body of the shield tunneling machine for advanced detection, a single detection method has certain limitations. In a plurality of natural irreparable contradictory subjects and objects consisting of detection distance, detection accuracy, detection speed, construction cost and construction speed, aiming at the advanced detection combination modes under different construction grading conditions, the trend of using a shield machine to carry out advanced detection is to realize advantage complementation and interference suppression of various detection technologies and combine long-distance detection and short-distance detection. For example, the combination of the transient electromagnetic method and the direct current method can make up for the defects of the transient electromagnetic method in detecting high resistance and blind areas, and can also make up for the defects that the direct current method is greatly influenced by the rear part and the side walls of the shield machine and is weakly sensitive to the abnormal body in front of the tunneling work, so that the separation of the abnormal body in front of and behind the tunneling work of the shield machine is realized. Preferably, the nuclear magnetic resonance method is similar to the arrangement of signal excitation coils and receiving coils of the transient electromagnetic method, and the principle is similar. However, the nuclear magnetic resonance can directly find water, which means that the nuclear magnetic resonance method is sensitive to water, so that the detection distance is generally below 30 meters under the condition of more water, and long-distance advanced detection cannot be realized. However, the detection distance of the transient electromagnetic method and the direct current method is about 100m, and although the detection precision of the water body and the definition of a detection interface are inferior to those of the nuclear magnetic resonance method, the nuclear magnetic resonance detection can be carried out in the shutdown state of the shield machine, so that the direct current method is assisted to realize accurate detection. Preferably, but in the detection mode of the combination of the plurality of advanced detection technologies, the problems of arrangement space and interference related to the transmission of the detection signals and the receiving signals aiming at different physical properties in the combination mode are the key of the combination of the different advanced detection technologies and the efficient tunneling crossing of the shield tunneling machine. Especially, in the advanced detection by using the shield machine, most of the underground tunnel space is occupied by the shield machine, which results in a very small space in front of and behind the tunnel face, for example, the direct current method uses an electrode disposed on a cutter or a cutter head 120 to contact with the tunnel face. The excitation coils of the transient electromagnetic method and the nuclear magnetic resonance method need to radiate electromagnetic signals under the condition of meeting the requirements of half space or full space, so that a plurality of excitation coils and transmitting coils need to be deployed in a narrow space between the shield machine and the tunnel face 500, the devices need to be disassembled after detection so that the shield machine can carry out tunneling, the construction time cost is increased, and the construction speed of the shield machine can be reduced. In the present invention, due to the dynamic configuration of the conductive entity 2511 and the conductive line segment 2512 of the coil assembly 250, the coil assembly can realize the conversion from the excitation current field to the excitation electromagnetic field, so that the combined mode of the advanced detection technologies for detecting different physical properties can realize continuous advanced detection and seamless switching of different advanced detection technologies under two working states of tunneling and stopping of the shield machine without complicated reconfiguration and large configuration space. The dynamic configuration of the conductive entities 2511 and conductive line segments 2512 of the coil sets 250 may be a dynamic change in the shape and deployment location on the cutterhead 120 of the conductive coils formed by the conductive entities 2511 and conductive line segments 2512. For example, the first detection coil 252 with the gap 300 formed by at least two conductive bodies 2511 can be used for detecting by passing a direct current excitation current field, and because of the gap 300, the current cannot form a closed loop and cannot excite an electromagnetic field. The conductive line segment 2512 is driven by the control module 210 to contact with the gap 300, so that the first detection coil 252 forms a closed loop to excite an electromagnetic field, meanwhile, since the plurality of conductive line segments 2512 can contact with the plurality of first detection coils 252, a second detection coil 253 in a closed loop form formed by the plurality of first detection coils 252 and the plurality of conductive line segments 2512 can be formed, and after an alternating current is applied, the directions of the electromagnetic fields excited by the first detection coil 252 and the second detection coil 253 are the same. In addition, the dynamic configuration of the conductive entity 2511 and the conductive line segment 2512 also includes the configuration of the shape and position of the second detection coil 253, for example, the first detection coil 252 formed by the conductive entity 2511 at different positions on the cutter head 120 and the second detection coil 253 formed by the conductive line segment 2512 in a circular shape, a rectangular shape, and the like. For example, the conductive line segment 2512 and the conductive body 2511 may form a plurality of second detection coils 253 axially spaced apart, and the closed surfaces formed by the plurality of second detection coils 253 at least partially overlap, as shown in fig. 7. Preferably, the dynamic configuration further comprises the first detection coil 252 and the second detection coil 253 formed by the conductive entity 2511 and the conductive line segment 2512 being switched according to the working state of the shield tunneling machine and the excitation signal of the control module 210. For example, the coil assembly 250 is in the form of a first detection coil 252 having a notch 300 in a state in which the shield machine is operating, and the coil assembly 250 is in the state in which the shield machine is stopped in which the closed surfaces of the plurality of second detection coils 253 are in a form in which they are at least partially overlapped with each other and axially spaced from each other when the second detection signal is excited.

Preferably, the coil assembly 250 is capable of switching between a current field and an electromagnetic field. The coil set 250 includes at least a transmitting coil 251 and a receiving coil 252. The transmitting coil 251 includes at least a plurality of conductive entities 2511 disposed on the cutterhead 120 of the shield machine body 100 and at least one conductive line segment 2512 located between the cutterhead 120 and/or the shield machine body 100 and the cutterhead 120. Preferably, as shown in fig. 4, at least two conductive entities 2511 are capable of forming the first detection coil 253 with the gap 300. The indentation 300 is capable of contacting the conductive line segment 2512 such that at least two conductive entities 2511 form a closed loop first detection coil 253. As shown in fig. 4, 5 and 6, 4 conductive entities 2511 constitute a first detection coil 253 with two gaps 300. And the notches 300 at both sides of the first detection coil 253 and the conductive line segment 2512 contact with each other, a closed loop can be formed. Preferably, the conductive entity 2511 and the conductive line segment 2512 can be made of conductive materials, such as metal and ceramic lamps. Preferably, the conductive entity 2511 may be circular as shown in fig. 4, or may be square or irregular polygonal. Preferably, the conductive entity 2511 can be in contact with the tunnel face 500 or the sidewall of the tunnel shielded by the shield machine body 100, thereby performing advanced detection based on a direct current method.

Preferably, the cutter deck 120 is provided with a first mounting portion 121 to which the first detection coil 253 is mounted. The cutter head 120 is also provided with a second mounting portion 122 to which a conductive wire segment 2512 is mounted. Preferably, the first mounting portion 121 is a plurality of slotted holes in an in-line array on the cutter head 120, as shown in fig. 3, 5 and 6. A first detection coil 253 formed of a conductive body 2511 is detachably mounted in the first mounting part 121. The removable means may be a screw thread step, a snap connection, etc. Preferably, the second mounting portion 122 may be located between the two first mounting portions 121, as shown in fig. 3. The second mounting portion 122 may be a recess capable of carrying a conductive wire segment 2512, as shown in fig. 5 and 6. Preferably, the first and second mounting

parts

121 and 122 may be made of an electromagnetic shielding material, or an inner wall thereof is provided with a layer of an electromagnetic shielding material. Preferably, the lead 600 is directly connected to the first detection coil 253 on the cutter head 120. The lead wire 600 may be connected to the detection gating module 240 through a conductive slip ring, so that the problem that the lead wire 600 is wound due to rotation with the first detection coil 253 in a state where the cutter head 120 is rotated can be avoided.

According to a preferred embodiment, the second mounting portion 122 is movable in the axial direction of the cutter disc 120. The second mounting portion 122 can move along the axial direction of the cutter head 120 through a rotating shaft of the shield tunneling machine main body 100, which drives the cutter head 120 to rotate. The second mounting portion 122 is slidably connected to the first mounting portion 121 such that the conductive line segment 2512 in the second mounting portion 122 is in an axially moving state so as to be able to contact the first detection coil 253 or be separated from the first detection coil 253, as shown in fig. 5 and 6. Preferably, different second mounting parts 122 shown in fig. 5 may be respectively coupled with the rotation shafts. With the above arrangement, when the conductive line segment 2512 does not contact the first detection coil 253, the first detection coil 253 is not a closed loop, and thus, after the first detection coil 253 contacts the tunnel face 500, a current excited by the first signal can be introduced into the surrounding rock of the tunnel face 500, so that a current field can be excited for detection.

According to a preferred embodiment, as shown in fig. 3, 7 and 8, at least two first detection coils 253 are circumferentially spaced about the center of the cutter deck 120. At least one conductive line segment 2512 is located between the two first detection coils 253.

According to a preferred embodiment, the control module 210 can be configured to drive the conductive line segment 2512 into contact with the indentations 300 of the plurality of first detection coils 253 such that the plurality of first detection coils 253 and the conductive line segment 2512 can form a closed loop of the second detection coil 254. Preferably, as shown in fig. 3, the four first detection coils 253 in the first mounting part 121 and the conductive line segments 2512 in the four second mounting parts 122 can contact each other to form a circular closed loop. The second detection coil 253 is capable of exciting an electromagnetic signal, which may be used for radiating the second detection signal of the transient electromagnetic method and/or radiating the third detection signal of the nuclear magnetic resonance method. Through the arrangement mode, the first detection coil 253 used for exciting current field detection and the second detection coil 254 used for exciting electromagnetic field detection can be formed through the conductive entity 2511 and the conductive line segment 2512 respectively, and the conversion of current field test and electromagnetic field test is realized, so that the seamless switching between the current field advanced detection method and the electromagnetic field detection method is realized in a mode of no need of re-disassembly and re-installation and deployment, the deployment time, labor cost and economic cost of the advanced detection device are obviously reduced, and meanwhile, the construction efficiency of the shield machine is also improved. Moreover, as opposed to frequent removal and installation of the excitation coil, the coil of the present invention is fixed to the cutter head 120, and the shape and orientation of the coil are fixed, facilitating deployment. In addition, for the current field detection mode of the first detection signal, the contact area between the first detection coil 253 and the tunnel face 500 is large, and the obtained measurement information is rich. More importantly, when the second detection signal and/or the third detection signal are probed with the second detection coil 254 in advance, the two notches 300 of the first detection coil 253 are in contact with the conductive line segment 2512, the first detection coil 253 thus forms a closed loop, so that its excited current field is converted into an electromagnetic field, and the direction of the electromagnetic field is the same as that of the electromagnetic field formed by the second detection coil 254, so that the first detection coil 253 does not interfere with the electromagnetic field formed by the second detection coil 254, and also increases the radiation gain of the second detection coil 254, particularly in the case where the first detection coil 253 is symmetrically distributed around the center of the cutter deck 120, the plurality of first detection coils 253 having the same electromagnetic field direction and being symmetrically distributed not only increase the radiation gain thereof but also focus the radiation direction of the second detection coil 254 to reduce the problem of electromagnetic field radiation divergence thereof.

Preferably, as shown in fig. 1, the lead detection device 200 further includes a detection pass module 240 and a receiving module 230. The detection gating module 240 controls whether the first detection signal, the second detection signal and/or the third detection signal are conducted with the coil assembly. After being turned on, the coil assembly 250 performs geological detection and transmits a response signal to the receiving module assembly 230. The receiving module group 230 transmits the response signal to the control module 210. Preferably, the control module 210 mainly implements tasks of data transmission and reception, switch control, and data processing. The control module 210 may include a processor and a memory. The memory is to store instructions. The processor is configured to store instructions by executing the memory. The Processor may be a Central Processing Unit (CPU), a general purpose Processor, a Digital Signal Processor (DSP), an Application-Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other Programmable logic device, transistor logic, hardware components, or any combination thereof. Preferably, the transmitting module 220 includes at least a first transmitting module 221, a second transmitting module 222, and a third transmitting module 223. Preferably, the first transmitting module 221 may transmit a first probe signal for passing a direct current. The second transmitting module 222 may be configured to transmit a second probe signal of the step electromagnetic pulse. The third transmitting module 223 may be configured to transmit a third detection signal having a larmor frequency.

Preferably, the first detection coil 253 is configured to receive the first detection signal transmitted by the transmission module group 220. The first detection coil 253 contacts with a face in front of the shield tunneling machine body 100 in a state where the cutter head 120 rotates to transmit the first detection signal and sense a change of the first detection signal, thereby transmitting the change of the first detection signal to the control module 210. Preferably, the detection gating module set 240 is connected to the control module 210, the transmission module set 220 and the coil set 250, respectively. In the case that the control module 210 transmits the first detection signal for dc detection through the first transmitting module 221 in the transmitting module group 220, the detecting gating module group 240 is configured to: the conduction of the first transmission module 221 and the plurality of first detection coils 253 is controlled based on a first enable signal generated by the control module 210 with respect to the first detection signal, as shown in fig. 1 and 8. The detection gating module 240 sequentially connects the two first detection coils 253 closest to each other and/or farthest from each other to the positive electrode and the negative electrode of the first transmission module 221, respectively. Preferably, the set of probing gating modules 240 includes at least one multi-way analog switch. For example, it may be a CD4067 analog switch that includes two 16-way switches. With this arrangement, each detection coil 253 on the cutter head 120 can be excited, and thus a large amount of information can be obtained in the implementation process of a simple algorithm. Preferably, the specific embodiments are as follows:

A. under the condition that the positive electrodes/negative electrodes connected to at least two conductive entities 2511 in the first detection coils 253 are the same, the detection gating module group 240 is configured to sequentially connect two first detection coils 253 closest to each other to the positive electrode and the negative electrode respectively; and/or sequentially connecting the two first detection coils 253 farthest away from each other to the positive pole and the negative pole respectively after traversing the two first detection coils 253 closest to each other.

B. Under the condition that the positive electrodes/negative electrodes accessed by the at least two conductive entities 2511 in the first detection coil 253 are different, the detection gating module group 240 is configured to sequentially access the at least two different conductive entities 2511 in the first detection coil 253 to the positive electrode and the negative electrode respectively; and/or after traversing all the detection coils 253, sequentially connecting the conductive entities 2511 connected with different positive and negative electrodes in the two first detection coils 253 which are closest to each other.

Preferably, in the case that any two first detection coils 253 are respectively connected to the positive pole and the negative pole of the first transmission module 221, the detection gating module group 240 transmits a first measurement signal for controlling the measurement sequence to the reception module group 230, that is, each time a pair of first detection coils 253 is switched on by the detection gating module group 240, the detection gating module group 240 generates the first measurement signal. Preferably, the receiving module set 230 comprises at least a first receiving unit 231 connected with a first detection coil 253. Preferably, the first receiving unit 231 is configured to sequentially measure the electrical signals between a plurality of two first detection coils 253 closest and/or farthest to each other, which are not connected to the first transmission module 221, based on the first measurement signal, as shown in fig. 8. Preferably, the first receiving unit 231 and transmits the electrical signal to the control module 210. Preferably, the electrical signal may be a change in electromotive force. Preferably, the first receiving unit 231 may be a data acquisition chip, a circuit, or the like. For example, it may be an ADC chip of model ADS 1256.

Preferably, by the above different excitation modes of the first detection coil 253, not only rich measurement data can be acquired, but also accurate measurement of resistivity values of different areas of different palm surfaces 500 can be realized.

Preferably, the second detection coil 254 is configured to receive the second detection signal and/or the third detection signal transmitted by the transmission module group 220 to radiate the second detection signal and/or the third detection signal to detect the geological structure in a state where the shield machine body 100 is stopped. The receiving coil 252 and the receiving module group 230 disposed corresponding to the receiving coil 252 receive the response signal returned by the second detection signal and/or the third detection signal. The receiving module group 230 is configured to transmit the response signal to the control module 210.

According to a preferred embodiment, the receiving module set 230 comprises a second receiving unit 232 connected with the receiving coil 252 to form a closed loop. Preferably, the second receiving unit 232 and the receiving coil 252 form a closed loop which is centered on the second detection coil 254, as shown in fig. 10. Preferably, the second receiving unit 232 at least comprises a synchronization line and an acquisition circuit and a communication serial port. With this arrangement, the receiving coil 252 and the second receiving unit 232 can receive the response signal in a central observation manner to detect the geological structure with a shallow depth. Preferably, the plurality of second receiving units 232 are symmetrically distributed on the tunnel face 500 and/or the side wall with the center of the second detection coil 254. Through the arrangement mode, the geological structure can be detected in a large-depth and large-area manner.

According to a preferred embodiment, in case the control module 210 transmits a second detection signal for transient electromagnetic detection through a second transmission module 222 within the transmission module set 220, the detection gating module set 240 is configured to: the second enable signal generated based on the control module 210 with respect to the second detection signal drives the second mounting portion 122 and/or the third mounting portion 110 to move in the axial direction of the cutter head 120 so that the plurality of conductive line segments 2512 contact the notches 300 of the plurality of first detection coils 253 to form the second detection coil 254 in which the first detection coil 253 and the conductive line 2512 form a closed loop. The detection gating module 240 turns on the second transmitting module 222 and the second detection coil 254 to radiate the second detection signal.

Preferably, in the case that the control module 210 transmits the third detection signal for nuclear magnetic resonance detection through the third transmitting module 223 in the transmitting module group 220, the detecting gating module group 240 is configured to: the third enable signal generated based on the control module 210 with respect to the third detection signal drives the second mounting portion 122 and/or the third mounting portion 110 to move in the axial direction of the cutter disc 120 such that the auxiliary coil 400 is in contact with the plurality of conductive line segments 2512 and the plurality of conductive line segments 2512 are in contact with the notches 300 of the plurality of first detection coils 253 to form a closed loop of the first detection coils 253. So that the first detection coil 253, the conductive wire 2512, and the auxiliary coil 400 can constitute the multi-turn second detection coil 254 of the closed loop. The detection gating module 240 switches on the third transmitting module 223 and the second detection coil 254 to radiate a third detection signal.

Preferably, the manner of using the second detection signal and/or the third detection signal for advanced detection is as shown in fig. 9. In the state that the shield machine is stopped, a plurality of receiving coils 252 and second receiving units 232 are arranged on the tunnel face 500 and/or the side wall, and the centers of closed loops formed by the receiving coils 252 and the second receiving units 232 are aligned with the center of the second detection coil 254. In the case where a plurality of closed loops formed by the receiving coil 252 and the second receiving unit 232 are disposed, the plurality of closed loops are distributed on the tunnel face 500 in such a manner as to be symmetrical with respect to the center of the second detection coil 254.

Preferably, a third mounting portion 110 for mounting the conductive line segment 2512 and movable in the axial direction of the cutterhead 120 is provided between the cutterhead 120 and the shield tunneling machine body 100, as shown in fig. 6. The third mounting portion 110 is provided in such a manner as to surround the cutter disc 120 in the axial direction. The third mounting portion 110 may carry at least one turn of the auxiliary coil 400 in a manner distributed in multiple layers along the axial direction of the shield machine body 100. The auxiliary coil 400 can be connected to at least the conductive line segment 2512 and the first detection coil 253, respectively, to form a multi-turn second detection coil 254, as shown in fig. 6. With this arrangement, when electromagnetic field detection is performed using the second detection signal and/or the third detection signal, the radiation power of the second detection coil 254 can be increased by changing the number of turns of the second detection coil 254.

According to a preferred embodiment, the plurality of first detection coils 253 are configured to be spaced apart from each other in a direction from the center of the cutter deck 120 and extend to the edge of the cutter deck 120. As shown in fig. 3 and 7, the plurality of first transmitting coils 253 can form an in-line array passing through the center of the cutter head 120, so that the measuring region of the front tunnel surface of the shield tunneling machine body 100 can be completely covered in a state where the cutter head 120 is rotated.

According to a preferred embodiment, the second mounting portions 122 are arranged in a manner so as to be distributed in multiple layers along the axial direction of the cutter disc 120. In the case where the plurality of first detection coils 253 are symmetrical about the center of the cutter disc 120, the plurality of first detection coils 253 can be brought into contact with the conductive line segment 2512 to form at least two polygonal closed-loop second detection coils 254 spaced from each other in the axial direction of the cutter disc 120. Preferably, the distance of separation may be 30 mm. The closed planes formed by the at least two polygonal closed-loop second detection coils 254 at least partially overlap each other. Preferably, as shown in fig. 7, three rectangular second detection coils 254 form a closed rectangular face array and overlap two by two. By this arrangement, the second detection coil 254 is formed to have a magnetic focusing characteristic, and is simple in design, and the magnitude of the excitation power and the spatial position arrangement of the coils can be changed.

Example 2

The embodiment discloses a geological advanced detection method, which comprises the step of performing geological advanced detection by adopting the shield machine based on geological advanced detection disclosed in the embodiment 1. Preferably, the advanced detection device 200 on the shield tunneling machine main body 100 at least comprises a control module 210, a transmitting module group 220, a receiving module group 230, a detection gating module group 240 and a coil group 250. Preferably, the method for geological advanced exploration comprises at least the following steps:

s100: the control module 210 controls the module 210 to transmit a first detection signal for direct current detection through a first transmission module 221 in the transmission module group 220 in a state that the shield tunneling machine main body 100 is in tunneling operation. The control module 210 generates a first enable signal based on the distribution state of the first detection coils 253 within the coil assembly 250, the operational state of the shield machine, and the time. Preferably, the first detection coil 253 is formed of at least two conductive entities 2511 with a gap 300. The indentation 300 is capable of contacting the conductive line segment 2512 such that at least two conductive entities 2511 form a closed loop first detection coil 253. As shown in fig. 4, 5 and 6, 4 conductive entities 2511 constitute a first detection coil 253 with two gaps 300. And the notches 300 at both sides of the first detection coil 253 and the conductive line segment 2512 contact with each other, a closed loop can be formed. Preferably, the conductive entity 2511 and the conductive line segment 2512 can be made of conductive materials, such as metal and ceramic lamps. Preferably, the conductive entity 2511 may be circular as shown in fig. 4, or may be square or irregular polygonal. Preferably, the conductive entity 2511 can be in contact with the tunnel face 500 or a sidewall of a tunnel shielded by the shield machine body 100.

S200: the detection gating module 240 sequentially connects the two first detection coils 253 closest to each other and/or farthest from each other to the positive electrode and the negative electrode of the first transmission module 221, respectively. Preferably, the set of probing gating modules 240 includes at least one multi-way analog switch. For example, it may be a CD4067 analog switch that includes two 16-way switches. With this arrangement, each detection coil 253 on the cutter head 120 can be excited, and thus a large amount of information can be obtained in the implementation process of a simple algorithm. Preferably, the specific embodiments are as follows:

S300: when any two first detection coils 253 are respectively connected to the positive electrode and the negative electrode of the first transmission module 221, the detection gating module group 240 transmits a first measurement signal for controlling the measurement sequence to the reception module group 230, that is, when a pair of first detection coils 253 is switched on by the detection gating module group 240, the detection gating module group 240 generates the first measurement signal. Preferably, the receiving module set 230 comprises at least a first receiving unit 231 connected with a first detection coil 253. Preferably, the first receiving unit 231 is configured to sequentially measure the electrical signals between a plurality of two first detection coils 253 closest and/or farthest to each other, which are not connected to the first transmission module 221, based on the first measurement signal, as shown in fig. 8. Preferably, the first receiving unit 231 and transmits the electrical signal to the control module 210. Preferably, the electrical signal may be a change in electromotive force. Preferably, the first receiving unit 231 may be a data acquisition chip, a circuit, etc., and may be an ADC chip with a model number ADS1256, for example. Preferably, at least one guard electrode is further provided in the axial direction of the cutter head 120. Or at least one annular electrode is arranged in the circumferential direction of the cutter head. With this arrangement, the current lines excited by the first detection coil 253 can be focused, and it is ensured that the current lines converge toward the center of the tunnel face 500.

S400: in the state that the shield machine main body 100 is stopped, a second detection signal for transient electromagnetic detection is transmitted through the second transmitting module 222 of the transmitting module group 220 and/or a third detection signal for nuclear magnetic resonance detection is transmitted through the third transmitting module 223 of the transmitting module group 220. The control module 210 generates the second enable signal and/or the third enable signal based on the operational state and the downtime of the shield machine. Preferably, the detection gating module group 240 is capable of driving the conductive line segment 2512 into contact with the notches 300 of the plurality of first detection coils 253 based on the second enable signal and/or the third enable signal, so that the plurality of first detection coils 253 and the conductive line segment 2512 can form the second detection coil 254 of the closed loop. Preferably, the second detection coil 253 is capable of exciting an electromagnetic signal, which may be used for radiating the second detection signal of the transient electromagnetic method and/or radiating the third detection signal of the nuclear magnetic resonance method. Through the arrangement mode, the first detection coil 253 used for exciting current field detection and the second detection coil 254 used for exciting electromagnetic field detection can be formed through the conductive entity 2511 and the conductive line segment 2512 respectively, and the conversion of current field test and electromagnetic field test is realized, so that the seamless switching between the current field advanced detection method and the electromagnetic field detection method is realized in a mode of no need of re-disassembly and re-installation and deployment, the deployment time, labor cost and economic cost of the advanced detection device are obviously reduced, and meanwhile, the construction efficiency of the shield machine is also improved. Moreover, as opposed to frequent removal and installation of the excitation coil, the coil of the present invention is fixed to the cutter head 120, and the shape and orientation of the coil are fixed, facilitating deployment. In addition, for the current field detection mode of the first detection signal, the contact area between the first detection coil 253 and the tunnel face 500 is large, and the obtained measurement information is rich. More importantly, when the second detection signal and/or the third detection signal are probed with the second detection coil 254 in advance, the two notches 300 of the first detection coil 253 are in contact with the conductive line segment 2512, the first detection coil 253 thus forms a closed loop, so that its excited current field is converted into an electromagnetic field, and the direction of the electromagnetic field is the same as that of the electromagnetic field formed by the second detection coil 254, so that the first detection coil 253 does not interfere with the electromagnetic field formed by the second detection coil 254, and also increases the radiation gain of the second detection coil 254, particularly in the case where the first detection coil 253 is symmetrically distributed around the center of the cutter deck 120, the plurality of first detection coils 253 having the same electromagnetic field direction and being symmetrically distributed not only increase the radiation gain thereof but also focus the radiation direction of the second detection coil 254 to reduce the problem of electromagnetic field radiation divergence thereof.

S500: the receiving coil 252 and the second receiving unit 232 connected with the receiving coil 252 to form a closed loop are used for receiving the response signal of the electromagnetic signal emitted by the second detection coil 254. Preferably, the second receiving unit 232 and the closed loop of the receiving coil 252 are located in the center of the second detection coil 254, as shown in fig. 10. Preferably, the second receiving unit 232 at least comprises a synchronization line and an acquisition circuit and a communication serial port. With this arrangement, the receiving coil 252 and the second receiving unit 232 can receive the response signal in a central observation manner to detect the geological structure with a shallow depth. Preferably, the plurality of second receiving units 232 are symmetrically distributed on the tunnel face 500 and/or the side wall with the center of the second detection coil 254. Through the arrangement mode, the geological structure can be detected in a large-depth and large-area manner. Preferably, the second receiving unit transmits the response signal to the control module 210.

S600: the control module 210 performs joint inversion analysis based on the obtained response signals and the electrical signals. Preferably, the electrical signal detected based on the first detection signal, the first response signal detected based on the second detection signal, the second response signal detected based on the third detection signal, and the working parameter are imported, and the electrical model is established for the electrical signal and the first response signal. For example, an electrical model can be established by using an equivalent conductive plane method, and an initial water content inversion model is established under the approximate assumption of linear inverse correlation of resistivity and water content. Based on the obtained electrical model, forward calculation of the second response signal can be realized by adopting a wired element method. For example, a plurality of grid cells with uniformly distributed physical properties may be discretized in space, that is, the initial amplitude of the second response signal may be regarded as the weighting of the kernel function of the plurality of cells, so that the second response signal is represented in a matrix form based on a measurement mode excited by a plurality of pulses, an objective function may be defined in a nonlinear fitting manner, and an optimal solution of the second response signal may be obtained in a case where the objective function is minimized. And initializing by using an inversion initial model based on the target function in an iterative inversion mode until the value of the target function is less than a given value or the iteration times are reached, thereby outputting a water content inversion result.

The word "module" as used herein describes any type of hardware, software, or combination of hardware and software that is capable of performing the functions associated with the "module".

It should be noted that the above-mentioned embodiments are exemplary, and that those skilled in the art, having benefit of the present disclosure, may devise various arrangements that are within the scope of the present disclosure and that fall within the scope of the invention. It should be understood by those skilled in the art that the present specification and figures are illustrative only and are not limiting upon the claims. The scope of the invention is defined by the claims and their equivalents.

Claims

1. A shield machine based on geological advanced detection at least comprises a shield machine body (100) and an advanced detection device (200) arranged on the shield machine body (100), wherein the advanced detection device (200) at least comprises a control module (210), a transmitting module group (220) and a coil group (250), the control module (210) is configured to transmit detection signals to the coil group (250) through the transmitting module group (220) for geological advanced detection, so that the control module (210) can realize joint inversion analysis of a geological three-dimensional model by receiving measurement data fed back by the coil group (250),

it is characterized in that the preparation method is characterized in that,

the control module (210) is further configured to:

transmitting a first detection signal for direct current detection through the transmitting module group (220) when the shield machine main body (100) is in a tunneling working state;

transmitting a second detection signal for transient electromagnetic detection and/or a third detection signal for nuclear magnetic resonance detection through the transmitting module group (220) when the shield machine main body (100) is in a state of stopping working; wherein the content of the first and second substances,

the first detection signal, the second detection signal and/or the third detection signal can be detected by the coil assembly (250) through a current field and an electromagnetic field;

the coil set (250) comprises at least a transmitting coil (251) and a receiving coil (252), wherein,

the transmitting coil (251) at least comprises a plurality of conductive entities (2511) arranged on a cutterhead (120) of the shield tunneling machine main body (100) and at least one conductive line segment (2512) positioned between the cutterhead (120) and/or the shield tunneling machine main body (100) and the cutterhead (120), wherein,

at least two of the conductive entities (2511) are capable of forming a first detection coil (253) with a gap (300) and the gap (300) is capable of contacting the conductive line segment (2512) such that the at least two conductive entities (2511) form a closed loop, wherein,

the first detection coil (253) is configured to receive the first detection signal transmitted by the transmission module group (220), and contacts with a tunnel face in front of the shield tunneling machine main body (100) in a state that the cutter head (120) rotates to transmit the first detection signal and sense the change of the first detection signal, so as to transmit the change of the first detection signal to the control module (210).

2. The shield machine of claim 1, wherein the control module (210) is configurable to drive the conductive line segment (2512) into contact with the notches (300) of the plurality of first detection coils (253) to enable the plurality of first detection coils (253) and the conductive line segment (2512) to form a closed loop second detection coil (254), wherein,

the second detection coil (254) is configured to receive the second detection signal and/or the third detection signal transmitted by the transmission module group (220) to radiate the second detection signal and/or the third detection signal to detect a geological structure in a state where the shield machine body (100) is stopped, wherein,

the receiving coil (252) and a receiving module group (230) arranged corresponding to the receiving coil (252) receive a response signal returned by the second detection signal and/or the third detection signal, and the receiving module group (230) is configured to transmit the response signal to the control module (210).

3. The shield machine of claim 2, wherein at least two of said first search coils (253) are circumferentially spaced about a center of said cutterhead (120) and at least one of said conductive line segments (2512) is located between two of said first search coils (253), wherein,

the blade disc (120) is provided with the installation first installation department (121) and the installation of first detection coil (253) electrically conductive line segment (2512) and can follow the axial displacement of blade disc (120) so that electrically conductive line segment (2512) with second installation department (122) and/or be in of electrically conductive entity (2511) contact be provided with between blade disc (120) and shield structure machine main part (100) be used for the installation electrically conductive line segment (2512) and can follow the axial displacement's of blade disc (120) third installation department (110), wherein,

the third installation part (110) is arranged in a mode of surrounding the axial direction of the cutter head (120) and can bear at least one number of auxiliary coils (400) in a mode of being distributed in a multilayer mode along the axial direction of the shield machine main body (100), and the auxiliary coils (400) can be at least connected with the electric wire segment (2512) and/or the first detection coil (253) so as to form a second detection coil (254) with multiple turns.

4. The shield tunneling machine according to claim 3, wherein the plurality of first detection coils (253) are arranged to be spaced apart from each other in a direction from the center of the cutter head (120) and extend to the edge of the cutter head (120), so that the plurality of first detection coils (253) can form an in-line array across the center of the cutter head (120) to cover the entire measurement area of the tunnel face in front of the shield tunneling machine body (100) in a state where the cutter head (120) is rotated.

5. The shield tunneling machine according to claim 4, wherein the second mounting portions (122) are arranged so as to be capable of being distributed in multiple layers in the axial direction of the cutter head (120) so that, in the case where a plurality of the first detection coils (253) are symmetrical about the center of the cutter head (120),

a plurality of the first detection coils (253) are contactable with the electrically conductive line segment (2512) to form at least two polygonal closed-loop second detection coils (254) spaced from each other in an axial direction of the cutter head (120), wherein,

the closed surfaces formed by the at least two polygonal closed loop second detection coils (254) at least partially overlap each other.

6. The shield tunneling machine according to claim 5, wherein the advanced detection device (200) further comprises a detection gating module set (240) respectively connected to the control module (210), the transmitting module set (220), and the coil set (250), wherein,

in case the control module (210) transmits a first probing signal for dc probing through a first transmitting module (221) within the set of transmitting modules (220),

the set of probe gating modules (240) is configured to:

controlling the conduction of a first transmission module (221) with a plurality of the first detection coils (253) based on a first enable signal generated by the control module (210) with respect to the first detection signals, wherein,

and sequentially connecting two first detection coils (253) which are closest and/or farthest to each other to the positive pole and the negative pole of the first transmission module (221) respectively, and transmitting a first measurement signal for controlling a measurement sequence to the receiving module group (230) under the condition that any two first detection coils (253) are connected to the positive pole and the negative pole of the first transmission module (221) respectively.

7. The shield tunneling machine according to claim 6, wherein the set of receiving modules (230) comprises at least a first receiving unit (231) connected with the first detection coil (253) and a second receiving unit (232) connected with the receiving coil (252) to form a closed loop, wherein,

the first receiving unit (231) is configured to sequentially measure an electrical signal between a plurality of two first detection coils (253) that are closest and/or farthest to each other, which are not accessed to the first transmission module (221), based on the first measurement signal, and transmit the electrical signal to the control module (210);

the second receiving unit (232) is located in the center of the second detection coil (254); or

The second receiving units (232) are symmetrically distributed on the tunnel face and/or the side wall with the center of the second detection coil (254).

8. A shield tunneling machine according to claim 7, characterized in that, in case the control module (210) transmits a second detection signal for transient electromagnetic detection through a second transmission module (222) within the set of transmission modules (220),

the set of probe gating modules (240) is configured to:

driving the second mounting part (122) and/or the third mounting part (110) to move along the axial direction of the cutter head (120) based on a second enabling signal generated by the control module (210) relative to the second detection signal so that a plurality of conductive line segments (2512) are in contact with notches (300) of a plurality of first detection coils (253) to form a second detection coil (254) which is formed by a first detection coil (253) of a closed loop and the conductive line segments (2512), and conducting the second transmitting module (222) and the second detection coil (254) to radiate the second detection signal;

or in case the control module (210) transmits a third detection signal for nuclear magnetic resonance detection via a third transmission module (223) within the set of transmission modules (220),

the set of probe gating modules (240) is configured to:

and driving the second mounting part (122) and/or the third mounting part (110) to move along the axial direction of the cutter head (120) based on a third enabling signal generated by the control module (210) relative to the third detection signal so that the auxiliary coil (400) is in contact with the plurality of conductive line segments (2512) and the plurality of conductive line segments (2512) are in contact with the notches (300) of the plurality of first detection coils (253) to form a first detection coil (253) of a closed loop, so that the first detection coil (253), the conductive line segments (2512) and the auxiliary coil (400) can form a multi-turn second detection coil (254) of the closed loop, and conducting the third transmitting module (223) and the second detection coil (254) to radiate a third detection signal.

9. A geological advance detection method, characterized by comprising the step of performing geological advance detection by using the geological advance detection-based shield tunneling machine according to any one of claims 1 to 8.