Exploration system, shield drilling machine and exploration method

Abstract

To provide a search system capable of calculating a distance to an underground unexcavated area outside of a shield excavator with high accuracy while easily handling any malfunction in a transceiver after a shield start, a shield excavator and a search method.SOLUTION: A search system 100 comprises a transceiver 101 mounted to the internal machine side of a steel member constituting a skin plate 21 or a bulkhead 22 at a front barrel 20 of a mud shield excavator 1 and sending a sound wave out of the machine and receiving a reflection wave reflected off the outside of the machine, and a PC 107 for calculating a distance to an underground loose part Xa on the basis of at least a received wave signal R at the transceiver 101, and the transceiver 101 sends a pulse wave at every predetermined frequency pitch as a sound wave successively in a predetermined frequency band.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an exploration system, a shield excavator, and an exploration method for calculating the distance to an unexcavated area underground outside the shield excavator. [Background technology]

[0002] With enclosed shield tunneling machines that build underground tunnels, the entire excavation surface is covered by the tunneling machine, making it impossible to visually check the ground conditions and difficult to detect signs of face collapse.Therefore, construction is carried out while maintaining the face set pressure calculated based on the soil cover and geological survey data.

[0003] In practice, excavation is performed while adjusting the set pressure as needed based on operational data such as the thrust of the shield machine and the rotational torque of the cutter, as well as measurements of the amount of excavated soil and the amount of ground surface displacement. However, operational data from the shield machine is only an indirect indicator for determining soil changes, and because the excavated soil volume varies in loosening rate depending on the soil type, it is difficult to evaluate the discrepancy between the set face pressure and the appropriate face pressure for the excavation situation in sections where soil changes occur. For this reason, observations of changes in the ground surface, buried objects, and nearby structures are also performed to evaluate the discrepancy, but because there is a time lag before changes appear on the ground surface, there is the possibility of widespread subsidence or uplift.

[0004] Therefore, for example, it has been proposed to mount an electromagnetic wave radar on the cutter head to directly measure the state of the ground near the shield excavator (see Patent Document 1). However, because the electromagnetic wave radar described in Patent Document 1 is attached to the cutter head outside the machine, once the shield excavator starts moving, it is in pressurized muddy water (or mud), so it is not possible to deal with any malfunctions in the electromagnetic wave radar. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 08-278371 Summary of the Invention [Problem to be solved by the invention]

[0006] Therefore, the present invention aims to provide an exploration system, a shield excavator, and an exploration method that can easily deal with any malfunctions that occur in the transmitter and receiver after the shield has been launched, and that can accurately calculate the distance to unexcavated areas underground outside the shield excavator. [Means for solving the problem]

[0007] This invention is an exploration system that includes a transceiver attached to the inside of a steel member that constitutes the outer shell or bulkhead of the body of a shield excavator, that transmits sound waves toward the outside of the machine and receives the waves reflected outside the machine, and a calculator that calculates the excavation range underground based on at least the information received by the transceiver, and that calculates the distance to an unexcavated area underground outside the machine of the shield excavator, and the transceiver is configured to sequentially transmit pulse waves at a predetermined frequency pitch as the sound waves in a predetermined frequency band. The transmitter / receiver is configured to sequentially transmit a plurality of pulse waves at a predetermined frequency pitch. Furthermore, the present invention is characterized in that the transmitter / receiver in the above exploration system is a shield excavator attached to the inside of the steel member.

[0008] The present invention is also an exploration method in which sound waves are transmitted from a transmitter / receiver attached to the inside of a steel member that constitutes the outer shell or bulkhead in the body of a shield excavator toward the outside of the machine, and the reflected waves are received from the outside of the machine, and the distance to an unexcavated area underground outside the machine of the shield excavator is calculated, and pulse waves at predetermined frequency intervals are transmitted sequentially as the sound waves in a predetermined frequency band. and sequentially transmitting a plurality of pulse waves at a predetermined frequency pitch. It is characterized by:

[0009] The shield excavator may be a mud pressure shield excavator such as an earth pressure balance type, mud pressurization type, or earth pressure water pressurization type, or a mud pressurization type shield excavator, or may be a TBM or the like if it is an enclosed type. The transceiver may be an integrated transceiver having both a transmitting function for transmitting sound waves and a receiving function for receiving sound waves, or may be configured with a transmitter for transmitting sound waves and a receiver for receiving sound waves separately.Furthermore, the transceiver may be a single unit, or multiple units may be used in combination. The above-mentioned phrase "sequentially transmitting a plurality of pulse waves at a predetermined frequency pitch" refers to the number of pulse waves transmitted consecutively at one time at each frequency.

[0010] This invention makes it possible to easily deal with any malfunctions that may occur in the transmitter / receiver after the shield has been launched, and also makes it possible to accurately calculate the distance to an unexcavated area underground outside the shield excavation machine. In more detail, a transmitter / receiver that transmits sound waves outside the machine and receives the reflected waves outside the machine is attached to the inside of the steel components that make up the outer shell and bulkheads in the body of the shield excavator, so that any malfunctions in the transmitter / receiver can be easily dealt with after the shield has launched.

[0011] On the other hand, since sound waves are transmitted from a transmitter / receiver attached to the inside of the steel member toward the outside of the machine, and when the reflected waves reflected outside the machine are received, sound waves that have passed through the steel member are transmitted and received, making it difficult to accurately calculate the distance to the unexcavated area underground outside the shield tunneling machine.

[0012] However, the transceiver of the present invention sequentially transmits pulse waves at a predetermined frequency pitch as the sound waves in a predetermined frequency band, that is, pulse waves of different frequencies are sequentially transmitted from the transceiver to the outside of the aircraft as sound waves.

[0013] The frequency of sound waves suitable for calculating the distance to the unexcavated area outside the machine varies depending on the soil quality and the surrounding environment, for example, because the transmitted sound waves are easily reflected from the unexcavated area outside the machine or because the sound waves are easily propagated through excavated soil. In contrast, as described above, pulse waves are sequentially transmitted as the sound waves at predetermined frequency intervals within a predetermined frequency band, so that pulse waves of a frequency suitable for calculating the distance to the unexcavated area inside the machine or a frequency close to that frequency can be transmitted from the transmitter / receiver. This allows the distance to the unexcavated area outside the machine to be calculated with high accuracy. Therefore, the size of overexcavated areas, such as loosened areas and overexcavated areas due to excavation, can be grasped outside the machine, and the presence or absence of signs of a natural ground collapse can be evaluated, for example.

[0014] Generally, the frequency of the sound waves suitable for calculating the distance to the unexcavated area underground outside the machine has a range, for example, it may be around 90 kHz, the predetermined frequency band may be 80 kHz to 100 kHz, and the predetermined frequency pitch may be 1 kHz. With the above-mentioned frequency band and frequency pitch, the distance to the unexcavated area underground outside the machine can be calculated with high accuracy without requiring an enormous measurement time.

[0015] Furthermore, since the above system has the transmitter and receiver mounted inside the shield tunneling machine, it can flexibly accommodate maintenance such as inspection and replacement of the transmitter and receiver during construction, as well as changes to the transmitter and receiver mounting position. Furthermore, with the above configuration, the distance to the unexcavated area underground outside the shield excavator can be accurately calculated without requiring any special structure in the shield excavator for measurements using the transmitter / receiver or for installing the transmitter / receiver.

[0016] Special structures include windows or holes that allow the transmitter / receiver to come into direct contact with the excavated soil or unexcavated areas, or waterproof structures for these, as well as incorporating waveguide materials of different materials into steel components to improve the transmission efficiency of sound waves.

[0017] The transmitter / receiver is configured to sequentially transmit a plurality of pulse waves at a predetermined frequency pitch. Therefore, the distance to the unexcavated area underground outside the machine can be calculated stably and accurately.

[0018] In more detail, when pulse waves at a predetermined frequency pitch are transmitted sequentially as the sound waves in a predetermined frequency band, if the pulse waves are transmitted one by one, it is difficult to transmit the pulse waves with sufficient or stable output, and it may become difficult to accurately calculate the distance to an unexcavated area underground outside the machine.

[0019] In contrast, by sequentially transmitting multiple pulse waves at a predetermined frequency pitch, pulse waves can be transmitted with sufficient and stable output, and the distance to an unexcavated area underground outside the machine can be calculated stably and accurately.

[0020] An example of multiple waves is a four-pulse wave. For example, a three-pulse wave can transmit pulse waves with sufficient and stable output compared to a single-pulse or two-pulse wave, but it is difficult to output a sufficient and stable output. Furthermore, depending on the distance to the unexcavated area, if five or more pulse waves are output, the reflected waves from the unexcavated area may interfere with the transmitted waves, making it difficult to accurately calculate the distance to the unexcavated area underground.

[0021] In another aspect of the present invention, the transceiver may be configured to transmit multiple pulse waves at a predetermined frequency pitch across the entire range of a predetermined frequency band, and the transceiver may further transmit multiple pulse waves at a predetermined frequency pitch across the entire range of the predetermined frequency band, the number of waves being different from the multiple waves.

[0022] With this invention, although the appropriate number of waves to transmit at one time varies depending on the soil quality and surrounding environment outside the machine, or the distance to the unexcavated area, because pulse waves are transmitted at multiple wave numbers, the distance to the unexcavated area underground outside the machine can be calculated stably and accurately.

[0023] In another aspect of the present invention, the transceiver transmits sound waves outside the aircraft, and a memory unit is provided to store the received information resulting from receiving the reflected waves reflected outside the aircraft, the transceiver sequentially transmits pulse waves at a predetermined frequency pitch as the sound waves in a predetermined frequency band, and stores the received information for each frequency pitch at which the reflected waves are received as individual data in the memory unit, and the calculator treats the individual data for each frequency pitch having different wave numbers across the entire range of the predetermined frequency band as a data set, generates specific data based on the data set, compares the generated specific data with the specific data of a different data set, and extracts the difference between the generated specific data and the specific data of the different data set.

[0024] According to this invention, although the appropriate pulse wave frequency varies depending on the soil quality and surrounding environment outside the machine, and the appropriate wave number of the pulse wave also varies depending on the distance to the unexcavated area, pulse waves of a certain frequency can be transmitted at a certain wave number, and individual data, which is received information as reflected waves, can be stored in a memory unit for multiple frequencies and different wave numbers. Then, by combining the individual data stored at multiple frequencies and different wave numbers into one data set, a data set including individual data generated by pulse waves at appropriate frequencies and appropriate wave numbers can be obtained. More specifically, data at wave numbers that are not sufficiently accurate among the individual data generated by pulse waves at appropriate wave numbers can be excluded, and individual data only for appropriate wave numbers can be generated.

[0025] In addition, by comparing a data set containing individual data from pulse waves at an appropriate frequency and an appropriate wave number with a data set acquired at a different time, and extracting the difference between the specific data of the different data set and the generated specific data, the distance to the unexcavated area underground outside the machine can be calculated with even greater accuracy.

[0026] Specifically, whether the comparison results of the specific data of the different data sets and the generated specific data are the same or different, the components of the reflected waves that reflect from the inside of the steel members that make up the outer shell and partition walls in the body of the shield excavator are included in both the specific data of the different data sets and the generated specific data.

[0027] Furthermore, the components of the reflected waves that reflect from the inside of the steel members that make up the outer shell and bulkheads in the body of the shield tunneling machine are larger than the components of the reflected waves that pass through the steel members and are reflected outside the machine, and there is a risk that the components of the reflected waves that are reflected outside the machine will be buried in the components of the reflected waves that reflect from the inside of the steel members.

[0028] Therefore, by extracting the difference between the specific data of the different data sets and the generated specific data, it is possible to exclude the components of the reflected waves that are reflected inside the steel members that make up the outer shell and bulkheads in the body of the shield excavator, and to reveal only the components of the reflected waves that are reflected outside the machine.The distance to the unexcavated area underground outside the machine can then be calculated with even greater accuracy using only the components of the reflected waves that are reflected outside the machine.

[0029] In another aspect of the present invention, a transmission path is provided for transmitting the received information from the transceiver to the memory unit, the transceiver is provided with an amplifier for amplifying the received information, and the transmission path for transmitting the received information to the memory unit is provided with an attenuator for attenuating the received information amplified by the amplifier and transmitted through the transmission path. The amplifier may be integrated with the transmitter / receiver or may be configured separately.

[0030] According to this invention, even if the received information transmitted through the transmission line is weak signal information and there is a risk of transmission loss or electrical noise interference during transmission, the received information is amplified and transmitted by an amplifier, and the transmitted received information is attenuated by an attenuator, so the received information can be accurately stored in the memory unit. Therefore, based on the accurately stored received information, the distance to the unexcavated area underground outside the machine can be accurately calculated. [Effects of the Invention]

[0031] The present invention provides an exploration system, shield excavator, and exploration method that can easily deal with malfunctions in the transmitter and receiver after the shield has been launched, and can accurately calculate the distance to unexcavated areas underground outside the shield excavator. [Brief explanation of the drawings]

[0032] [Figure 1] Schematic longitudinal cross-sectional view of an earth pressure shield excavator underground. [Figure 2] AA arrow view in FIG. 1. [Figure 3] Schematic block diagram of the exploration system. [Figure 4] 1 is a flow diagram of an exploration method in an exploration system. [Figure 5] 1 is a flow diagram of an exploration method in an exploration system. DETAILED DESCRIPTION OF THE INVENTION

[0033] An embodiment of the present invention will be described with reference to FIGS. 1 shows a schematic vertical cross-sectional view of an earth pressure shield excavator 1 underground, FIG. 2 shows a view taken along the line AA in FIG. 1, and FIG. 3 shows a schematic block diagram of an exploration system 100. As shown in FIG.

[0034] 4 and 5 show a flow diagram of the exploration method in the exploration system 100. In FIG. 1, the side of the cutter head 10 relative to a front body 20 (described later) is designated as the front F, and the side of the rear body 30 relative to the front body 20 is designated as the rear B.

[0035] The mud pressure shield excavator 1 shown in Figures 1 and 2 is a center-bending, rear-body-pushing mud pressure shield excavator. The mud pressure shield excavator 1 cuts the natural ground X with a rotating cutter head 10 while injecting additives such as bentonite, and excavates while balancing the earth pressure at the face with the thrust and soil discharge volume of the mud pressure shield excavator 1. The mud pressure shield excavator 1 is composed of the cutter head 10, front body 20, and rear body 30, from the front F to the rear B, and is circular in side view.

[0036] The cutter head 10 is composed of a radially outer ring portion 11 and multiple spokes 13 that connect the ring portion 11 and the central shaft portion 12 in the radial direction, and multiple cutting bits 14 are provided at predetermined intervals between the spokes 13 and the ring portion 11. The positions of the multiple cutting bits 14 from the center of the cutter head 10 on the spokes 13 can be adjusted, allowing the entire surface of the rotating cutter head 10 to be cut.

[0037] Furthermore, a fishtail 15 is provided at the front F of the central shaft portion 12. The cutter head 10 configured in this manner is provided with an injection port at the front F of the cutter head 10 for injecting an additive, although this is not shown.

[0038] The front body 20 is composed of an inverted cylindrical steel skin plate 21 and a partition wall 22 provided at a position a predetermined distance rearward B from the front end F of the skin plate 21. A chamber 40 is formed in the space forward F of the partition wall 22 and rearward B of the cutter head 10.

[0039] The central shaft 12 of the cutter head 10 penetrates the center of the partition wall 22 in a side view, and a plurality of motors 23 for rotating the cutter head 10 are concentrically arranged around the central shaft 12. A screw conveyor 24 is also provided, connected to the lower part of the partition wall 22 and extending to the rear of the rear body 30. The front end F of the screw conveyor 24 penetrates the partition wall 22 and is inclined upward from the front end F to the rear end B. The screw conveyor 24 includes a shaft-mounted screw 241 therein, the end of which at the front end F extends to the chamber 40.

[0040] In addition, a plurality of center-bending jacks 25 are provided inside the skin plate 21. The bending jacks 25 are arranged in multiple locations circumferentially with the front end F pivoted to the rear end B of the bulkhead 22 and the rear end B pivoted to the front end F of the rear fuselage 30 described later, and are used to adjust the orientation of the front fuselage 20 relative to the rear fuselage 30 by the amount of extension and contraction of the bending jacks 25. In addition, above the partition wall 22, there is provided a hatch 27 which, when opened, leads to a chamber 40 outside the aircraft and is hermetically sealed.

[0041] The rear fuselage 30 is provided with an erector 32 at the front F for assembling the segments S, which are divided into multiple pieces, inside a skin plate 31, which is a cylindrical steel member to which the segments S are assembled. The rear fuselage 30 also has multiple rows of tail brushes 33 arranged circumferentially on the inner peripheral surface at the rear B of the skin plate 31 to fill in the gaps between the outer surface of the assembled S and the inner peripheral surface of the skin plate 31.

[0042] In addition, a plurality of propulsion jacks 34 are provided inside the skin plate 31. The propulsion jacks 34 are jacks that are pressed against the end faces of the front F of the segments S assembled inside the rear body 30, and use the segments S as a reaction force to move the mud pressure shield excavator 1 forward F, and multiple propulsion jacks 34 are arranged at predetermined intervals around the circumference. Note that the propulsion jacks 34 may also be provided on the front body 20.

[0043] At the rear B of the mud pressure shield excavator 1 configured in this manner, a trailing carriage is provided inside the assembled segments S, and equipment such as a track is provided for a muck carriage that carries out the excavated soil discharged from the screw conveyor 24. In addition, appropriate devices and equipment such as a shape retention device for ensuring the roundness of the assembled segments S and ventilation equipment may be provided.

[0044] The mud pressure shield excavator 1 configured in this manner rotates the cutter head 10 while injecting additive material from an injection port (not shown) toward the working face, and cuts the natural ground X with the rotating cutting bit 14. The excavated soil cut by the cutting bit 14 is stirred in the chamber 40 and taken into the machine from the screw conveyor 24 by the shaft-mounted screw 241 that extends into the chamber 40. The excavated soil discharged from the screw conveyor 24 is carried out of the tunnel by a muck cart.

[0045] In addition, the excavated soil discharged from the screw conveyor 24 can be transported not only by a muck cart, but also by a belt conveyor or a pressure pump connected to a pressure pipe (soil discharge pipe) installed behind the screw conveyor 24, and transported by the belt conveyor or pressure pipe.

[0046] As the cutter head 10 excavates the natural ground X, the extension of the propulsion jack 34 is controlled, and the assembled segment S acts as a reaction force to move the mud pressure shield excavator 1 forward. When the mud pressure shield excavator 1 has advanced by the ring length of the segment S, cutting of the natural ground X by the cutter head 10 is stopped, and inside the rear body 30, the multiple divided pieces are assembled by the erector 32 to complete the segment S.

[0047] The earth pressure shield excavator 1 repeats this construction process as one cycle and excavates. When the cutter head 10 excavates the natural ground X, the cutting face is usually cut along the trajectory of the cutting bit 14 (see trajectory line L shown in Figure 1). However, depending on the geological condition of the natural ground X, for example, the excavation may be extended beyond the trajectory of the cutting bit 14. When the excavation is extended beyond the trajectory of the cutting bit 14 in this way, a loosened portion Xa such as a loosened portion or an over-excavated portion may be formed in the upper part of the earth pressure shield excavator 1 or the like due to excavation.

[0048] If the loosened portion Xa becomes large, there is a risk that the tunnel face will collapse, so it is important to grasp the size of the loosened portion Xa, which is formed outside the enclosed earth pressure shield excavator 1 and cannot be seen from inside the earth pressure shield excavator 1. Therefore, the following describes an exploration system 100 that explores the loosened portion Xa.

[0049] As shown in Figure 3, the exploration system 100 is composed of multiple transmitters and receivers 101 called sonars, a preamplifier 102, a multiplexer 103, an attenuator 104, a pulser receiver 105, and a transmission path 106 and PC 107 that connect these to a personal computer 107 (hereinafter referred to as PC 107).

[0050] The transceiver 101 is disposed inside the earth pressure shield excavator 1 (hereinafter referred to as the inside of the machine), and transmits pulse waves into the ground and receives waves reflected from the ground. Note that a plurality of transceivers 101 are provided, and a preamplifier 102 is connected to each transceiver 101.

[0051] The preamplifier 102 is provided for each transceiver 101 and is connected to the multiplexer 103 , amplifies the received wave signal R received by the transceiver 101 , and transmits the amplified signal to the multiplexer 103 .

[0052] The multiplexer 103 is connected to a plurality of transceivers 101 , a preamplifier 102 connected to each transceiver 101 , an attenuator 104 , and a pulser receiver 105 . The multiplexer 103 is configured to transmit pulsed ultrasonic transmission wave signals T to each of the multiple transceivers 101 connected thereto, and also to combine pulsed ultrasonic reception wave signals R received by the transceivers 101 and transmit them to the pulser receiver 105 via the attenuator 104. The multiplexer 103 is also called a multiplexer, multiplexing device, multiplexing device, or combiner. The attenuator 104 is an attenuator that attenuates the received wave signal R, which is a pulse wave amplified by the preamplifier 102 and transmitted from the multiplexer 103 , and transmits the attenuated signal to the pulser receiver 105 .

[0053] As described above, the pulser receiver 105 is connected to the PC 107 via the transmission line 106 and is configured to generate a pulse wave as a transmission wave signal T and transmit it to the multiplexer 103 under the control of the PC 107 .

[0054] In addition, the pulser receiver 105 is configured to transmit the received wave signal R, which is a pulse wave amplified by the preamplifier 102, transmitted from the multiplexer 103, and further attenuated by the attenuator 104, to the PC 107 via the transmission path 106 described later. The transmission path 106 connects the transceiver 101, the preamplifier 102, the multiplexer 103, the attenuator 104, the pulser receiver 105, and the PC 107 so that electrical signals can be transmitted between them.

[0055] The PC 107 functions as a memory unit that stores the received wave signal R, and also functions as a calculator that calculates the distance to the boundary surface Xb of the ground X outside the loosened portion Xa and the propagation speed of the excavated soil based on the transmission control information output to the pulser receiver 105 and the received wave signal R transmitted from the pulser receiver 105.

[0056] The preamplifier 102, multiplexer 103, attenuator 104, pulser receiver 105, transmission path 106 and PC 107, together with the transceiver 101, are arranged inside the machine and are configured to be able to communicate with a management PC located inside the tunnel outside the machine or in a management room outside the tunnel via a LAN circuit or the like not shown.

[0057] The above-mentioned transceiver 101 will be described in further detail below. As shown in Figures 1 and 2, the transceiver 101 (101a, 101b) is attached to the skin plate 21 and the bulkhead 22, and transmits sound waves that mainly exhibit a pulse waveform (hereinafter referred to as pulse waves). The transceiver 101 (101a, 101b) is also configured to receive reflected waves reflected from the boundary surface Xb between the loosened portion Xa and the natural ground X, etc.

[0058] Specifically, the transceiver 101a is attached to the upper part of the inside of the bulkhead 22 of the earth pressure shield excavator 1, and transmits a transmission wave, which is a pulse wave, toward the front F. The transceiver 101a also receives a reflected wave, which is a pulse wave reflected by the natural ground X in the front F.

[0059] The transceiver 101b is attached to the upper part of the inner peripheral surface of the skin plate 21, and transmits a transmission wave, which is a pulse wave, toward a loosened portion Xa formed at the upper part of the forward portion F of the forward body 20. The transceiver 101b also receives a reflected wave, which is a pulse wave reflected at the boundary surface Xb between the loosened portion Xa and the natural ground X outside the loosened portion Xa. As shown in FIG. 2, a plurality of transceivers 101b are provided at predetermined intervals in the circumferential direction.

[0060] In this way, the transmitter / receiver 101 attached to the inner surface of the bulkhead 22 or the skin plate 21 is attached in close contact with the inboard side surface of the bulkhead 22 or the inner peripheral surface of the skin plate 21 without leaving any gaps. For this reason, the mounting surface of the transceiver 101 is formed to fit the shape of the inboard side of the bulkhead 22 and the inner peripheral surface of the skin plate 21. In addition, the transceiver 101 is mounted with a highly durable gel-like sheet (not shown) interposed between the inboard side of the bulkhead 22 or the inner peripheral surface of the skin plate 21 and the transceiver 101. The transceiver 101 may also be mounted to the bulkhead 22 or the skin plate 21 using a mounting base (not shown) that can be screwed in or a magnetic mounting jig (not shown) that generates a reaction force of about several hundred kN.

[0061] In the exploration system 100 configured in this manner, the pulser receiver 105 generates a transmission wave signal T, which is a pulse wave, under the transmission control of the PC 107, and transmits it to the multiplexer 103. The multiplexer 103, which has received the transmission wave signal T from the pulser receiver 105, transmits the transmission wave signal T to the multiple transceivers 101.

[0062] The transceiver 101a to which the transmission wave signal T has been transmitted transmits a transmission wave, which is a pulse wave, toward the front F through the bulkhead 22. Similarly, the transceiver 101b to which the transmission wave signal T has been transmitted transmits a transmission wave toward the outside of the forward fuselage 20 through the skin plate 21.

[0063] The acoustic impedance differs between the loosened portion Xa and the consolidated natural ground X outside it. Therefore, the transmitted wave transmitted from the transceiver 101 passes through the loosened portion Xa and is reflected at the boundary surface Xb between the loosened portion Xa and the natural ground X. The reflected wave, which is a pulse wave reflected at the boundary surface Xb between the loosened portion Xa and the natural ground X, is received by the transceiver 101 via the partition wall 22 and the skin plate 21.

[0064] The reflected wave received by the transceiver 101 is amplified by the preamplifier 102 as a received wave signal R and transmitted to the multiplexer 103, and the multiplexer 103 transmits the transmitted received wave signal R to the pulser receiver 105 via the attenuator 104. The PC 107 calculates the length of the slack portion Xa based on the received wave signal R transmitted from the pulser receiver 105.

[0065] This will be explained in detail below with reference to FIGS. First, a predetermined number of pulse waves (three waves at first) of a predetermined frequency are transmitted from the transceiver 101 to the outside of the device (step s1). Specifically, the frequency is changed by 1 kHz increments within the frequency band of 80 kHz to 100 kHz. In addition, in one pulse wave transmission, transmission of three waves and transmission of four waves are performed across the entire frequency band, forming one set. Therefore, 21 transmissions are performed by changing the frequency, and this is repeated with different wave numbers, resulting in a total of 42 measurements being performed in one set. Therefore, first, three waves of 80 kHz pulse waves are transmitted consecutively.

[0066] The transmitted wave is reflected underground and received as a received wave signal R by the transceiver 101 (step s2). The received wave signal R received by the transceiver 101 is amplified by the preamplifier 102 and transmitted via the transmission path 106 via the multiplexer 103 and the attenuator 104 (step s3).

[0067] The received wave signal R transmitted through the transmission path 106 is amplified by the preamplifier 102 and is therefore attenuated by the attenuator 104 (step s4), and the attenuated received wave signal R is stored as individual data in the PC 107, which functions as a memory unit, via the pulser receiver 105 (step s5).

[0068] If measurement of the entire range of the predetermined frequency band (80 kHz to 100 kHz) has not been completed (step s6: No), the frequency is changed by a predetermined frequency pitch (1 kHz) and set (step s7), and the process returns to step s1 to transmit pulse waves of the set frequency at a predetermined wave number from the transceiver 101. This process is repeated over the entire range of the predetermined frequency band (80 kHz to 100 kHz) while changing the frequency by the predetermined pitch.

[0069] When the measurement of the entire range of the predetermined frequency band (80 kHz to 100 kHz) is completed (step s6: Yes), it is determined whether the measurement of the set wave numbers (3 waves and 4 waves) is completed. If the measurement at the set wave numbers (3 waves and 4 waves) is not completed (step s8: No), the wave number is changed to the set wave number (4 waves) (step s9), and the process returns to step s1, where pulse waves of a predetermined frequency in a predetermined frequency band are transmitted at the set wave number from the transceiver 101. This is repeated over the entire range of the predetermined frequency band (80 kHz to 100 kHz) while changing the frequency by a predetermined pitch.

[0070] When the measurement is completed at the changed wave number over the entire range of the specified frequency band (80 kHz to 100 kHz) by changing the specified frequency pitch in increments (step s8: Yes), that is, when one set of measurements is completed, PC 107 puts all the individual data into a data set, blends all the individual data in the data set to generate specific data, and stores it in PC 107 (step s10).

[0071] In order to eliminate the influence of the less accurate first, second, and third wave measurement results in a data set, the first, second, and third wave components are removed from the four-wave measurement results consisting of the first, second, third, and fourth wave components. Specifically, the four-wave measurement results consisting of the first, second, and third wave components are divided by the three-wave measurement results consisting of the first, second, and third wave components to generate specific data. This allows for the generation of specific data consisting only of the highly accurate fourth wave.

[0072] The PC 107, which functions as a computing unit, determines whether specific data of another data set is stored, and if the specific data of another data set is not stored in the PC 107 (step s11: No), the process returns to step s1 and measurement is resumed. Note that another data set is the result of measurement performed at another timing, that is, the data set of the measurement result performed immediately before.

[0073] If the specific data of the other data set is stored in the PC 107 (step s11: Yes), the PC 107 compares the stored specific data of the other data set with the specific data generated in step s10 (step s12).

[0074] Then, the PC 107 determines whether the comparison results match, and if they match (step s13: Yes), the state of the received wave signal R has not changed, so the process returns to step s1 and measurement is resumed.

[0075] Conversely, if the determination result by the PC 107 is that they do not match (step s13: No), the difference between the specific data of another data set and the generated specific data is extracted, and the distance to the unexcavated area is calculated (step s14).

[0076] In more detail, whether the comparison results of the specific data of another data set and the generated specific data are the same or different, the components of the reflected waves reflected from the inside of the skin plate 21 in the front body 20 of the mud pressure shield drilling machine 1 are included in both the specific data of the other data set and the generated specific data.

[0077] In addition, the components of the reflected waves reflected inside the skin plate 21 in the front body 20 of the mud pressure shield excavator 1 are larger than the components of the reflected waves that pass through the skin plate 21 and are reflected outside the front body 20, and there is a risk that the components of the reflected waves reflected outside the front body 20 will be buried in the components of the reflected waves reflected inside the skin plate 21.

[0078] Therefore, by extracting the difference between the specific data of another data set and the generated specific data, it is possible to exclude the component of the reflected wave reflected inside the skin plate 21 in the front body 20 of the mud pressure shield excavator 1, and to reveal only the component of the reflected wave reflected outside the front body 20. Then, the distance from the skin plate 21 to the natural ground X, that is, the length of the loosened portion Xa (section length l M ) can be calculated more accurately.

[0079] There are various methods for calculating the distance to the unexcavated area, but for example, the distance can be calculated by the following method. Specifically, the PC 107 calculates the measurement time (t) and the propagation velocity C M Based on this, the distance from the skin plate 21 to the natural ground X, that is, the length of the loosened portion Xa (section length l M ) is calculated.

[0080] The measurement time (t) is the time from sending the pulse wave to receiving the reflected wave, and the propagation speed is C M is the speed at which the pulse wave (transmitted wave and reflected wave) propagates through the excavated soil. In addition, the propagation speed C M may be set in advance based on the soil quality of the construction site obtained by test excavation or the like, or the propagation speed of the excavated soil inside the chamber 40 may be used.

[0081] As described above, the exploration system 100 is provided with a transceiver 101 that is attached to the inside of the steel member that constitutes the skin plate 21 in the front body 20 of the mud pressure shield excavator 1, and that transmits sound waves outside the machine and receives reflected waves outside the machine, and a PC 107 that calculates the loosened portion Xa underground based on at least the received wave signal R in the transceiver 101, and the PC 107 calculates the distance to the underground ground X outside the mud pressure shield excavator 1.Since the transceiver 101 sequentially transmits pulse waves at a predetermined frequency pitch in a predetermined frequency band as sound waves, it can easily deal with any malfunction of the transceiver 101 after the mud pressure shield excavator 1 starts, and can accurately calculate the distance to the underground ground X outside the mud pressure shield excavator 1, i.e., the length of the loosened portion Xa.

[0082] In more detail, a transceiver 101 that transmits sound waves outside the mud pressure shield excavator 1 and receives reflected waves outside the mud pressure shield excavator 1 is attached to the inside of the machine, such as the skin plate 21 or bulkhead 22, in the front body 20 of the mud pressure shield excavator 1, so that even if a malfunction occurs in the transceiver 101 after the mud pressure shield excavator 1 has started, it can be easily dealt with.

[0083] On the other hand, when transmitting sound waves from the transmitter / receiver 101 attached to the inside of the front body 20, which is a steel member, to the outside of the machine and receiving the reflected waves reflected outside the machine, the sound waves that have passed through the steel member are transmitted and received. Therefore, the distance to the underground mound X outside the machine of the mud pressure shield excavator 1, that is, the length of the loosened portion Xa (section length l M ) becomes difficult to calculate accurately.

[0084] However, the transceiver 101 transmits pulse waves at a predetermined frequency pitch (1 kHz) as sound waves in a predetermined frequency band (80 kHz to 100 kHz), that is, pulse waves of different frequencies are transmitted from the transceiver 101 to the outside of the device as sound waves.

[0085] The frequency of sound waves suitable for calculating the distance to the underground pile X outside the machine varies depending on the soil quality and the surrounding environment, for example, because the transmitted sound waves are easily reflected by the underground pile X outside the machine, or the sound waves are easily propagated by excavated soil. In contrast, as described above, pulse waves at a predetermined frequency interval (1 kHz) are transmitted as sound waves in a predetermined frequency band (80 kHz to 100 kHz), so that pulse waves at a frequency suitable for calculating the distance to the underground pile X or a frequency close to that frequency can be transmitted from the transceiver 101.

[0086] Therefore, due to the difference in transmission and reflection characteristics outside the steel plate due to differences in frequency, it is possible to select and analyze frequencies and wavelengths that pass through the cutting and mixing sand, mud, and gravel outside the shield machine and appropriately capture the reflection from the base surface.In addition, it is possible to utilize frequency bands that have a large attenuation effect on multiple reflections within the thickness cross section of the steel plate.

[0087] Furthermore, the time difference required for the signal to travel back and forth through the thickness of the steel plate, i.e., the phase difference, creates an attenuation effect, suppressing multiple reflections within the steel plate and allowing the thickness of the outer layer of crushed sand, mud, and gravel, i.e., the reflection from the base surface beyond, to be properly captured.

[0088] Therefore, the distance to the underground natural ground X outside the machine can be calculated with high accuracy. Therefore, it is possible to grasp the size of the over-excavation area, such as the area that has become loose due to excavation or the over-excavation area outside the machine, and it is possible to evaluate, for example, whether there is a sign of a natural ground collapse.

[0089] Furthermore, since the transmitter / receiver 101 transmits multiple pulse waves (three or four waves) at a predetermined frequency pitch (1 kHz), the distance to the underground pile X outside the device can be calculated stably and accurately.

[0090] In more detail, when transmitting pulse waves at a predetermined frequency pitch (1 kHz) as sound waves in a predetermined frequency band (80 kHz to 100 kHz), if the pulse waves are transmitted one by one, it is difficult to transmit the pulse waves with sufficient or stable output, and there is a risk that it will be difficult to accurately calculate the distance to the underground pile X outside the machine.

[0091] In contrast, by transmitting multiple pulse waves (3 or 4 waves) at a predetermined frequency pitch (1 kHz), it is possible to transmit pulse waves with sufficient and stable output, and the distance to the underground mass X outside the device can be calculated stably and accurately.

[0092] When the number of pulse waves is three, the pulse waves can be transmitted with sufficient and stable output compared to when there is one or two waves, but it is difficult to output a sufficient and stable output. Furthermore, depending on the distance to the natural ground X, when five or more pulse waves are output, the reflected waves from the natural ground X may interfere with the transmitted waves, making it difficult to accurately calculate the distance to the underground natural ground X.

[0093] Furthermore, the transceiver 101 transmits multiple waves (three waves) of pulse waves at a predetermined frequency pitch (1 kHz) across the entire range of a predetermined frequency band (80 kHz to 100 kHz), and the transceiver 101 transmits pulse waves at a predetermined frequency pitch (1 kHz) across the entire range of a predetermined frequency band (80 kHz to 100 kHz) at different wave numbers (four waves) from the multiple waves. Therefore, although the appropriate number of waves to transmit at one time differs depending on the soil quality and surrounding environment outside the device, or the distance to the natural ground X, the pulse waves are transmitted at multiple wave numbers (three waves, four waves) and blended to eliminate the influence of the less accurate first, second, and third waves, so that the distance to the underground natural ground X outside the device can be calculated stably and accurately.

[0094] In addition, the transceiver 101 transmits sound waves outside the aircraft, and a PC 107 is provided that stores the received wave signal R, which is the result of receiving the reflected waves reflected outside the aircraft.The transceiver 101 transmits pulse waves as sound waves at a predetermined frequency pitch (1 kHz) in a predetermined frequency band (80 kHz to 100 kHz), and stores the received wave signal R at each frequency pitch (1 kHz) at which the reflected waves are received in the PC 107 as individual data.The PC 107 treats the individual data for each frequency pitch (1 kHz) and for all wave numbers (3 waves, 4 waves) across the entire predetermined frequency band (80 kHz to 100 kHz) as a data set, generates specific data based on the data set, compares the generated specific data with the specific data of a different data set, and extracts the difference between the generated specific data and the specific data of the different data set.

[0095] Therefore, although the appropriate pulse wave frequency varies depending on the soil quality and surrounding environment outside the device, and further the appropriate wave number of the pulse wave varies depending on the distance to the natural ground X, etc., pulse waves of a certain frequency are transmitted at a certain wave number, and individual data, which is the received wave signal R received as the reflected wave, can be stored in PC 107 for a plurality of frequencies and different wave numbers. Then, by combining the individual data stored for a plurality of frequencies and different wave numbers into one data set, a data set can be obtained that includes individual data from pulse waves at an appropriate frequency and appropriate wave number.

[0096] Furthermore, by comparing a data set containing individual data from pulse waves at an appropriate frequency and an appropriate wave number with a data set acquired at a different time, and extracting the difference between the specific data in the different data set and the generated specific data, that is, by extracting the difference between the data sets, the distance to the underground mass X outside the aircraft can be calculated with even greater accuracy.

[0097] Specifically, whether the comparison results of the specific data of a different data set and the generated specific data are the same or different, the components of the reflected waves reflected from the inside of the skin plate 21 in the front body 20 of the mud pressure shield drilling machine 1 are included in both the specific data of the different data set and the generated specific data.

[0098] In addition, the components of the reflected waves reflected inside the skin plate 21 in the front body 20 of the mud pressure shield excavator 1 are larger than the components of the reflected waves that pass through the skin plate 21 and are reflected outside the machine, and there is a risk that the components of the reflected waves reflected outside the machine will be buried in the components of the reflected waves reflected inside the skin plate 21.

[0099] Therefore, by extracting the difference between the specific data of different data sets and the generated specific data, it is possible to exclude the components of the reflected waves that are reflected inside the skin plate 21 in the front body 20 of the earth pressure shield excavator 1 and make clear only the components of the reflected waves that are reflected outside the machine. Then, it is possible to calculate with even greater accuracy the distance to the unexcavated area underground outside the machine using only the components of the reflected waves that are reflected outside the machine.

[0100] Furthermore, a transmission path 106 is provided for transmitting the received wave signal R from the transceiver 101 to the PC 107, and the transceiver 101 is provided with a preamplifier 102 for amplifying the received wave signal R, and an attenuator 104 is provided between the multiplexer 103 and the pulser receiver 105 for attenuating the received wave signal R amplified by the preamplifier 102 and transmitted through the transmission path 106. Therefore, even if the received wave signal R transmitted through the transmission path 106 is weak signal information and there is a risk of transmission loss or electrical noise interference during transmission, the received wave signal R is amplified and transmitted by the preamplifier 102 and the transmitted received wave signal R is attenuated by the attenuator 104, so that the received wave signal R can be accurately stored in the PC 107. Therefore, the distance to the underground mass X outside the aircraft can be calculated with high accuracy based on the accurately stored received wave signal R.

[0101] As described above, the transmitter / receiver 101 is attached to the skin plate 21 or the bulkhead 22 of the front body 20 of the mud pressure shield excavator 1, and transmits pulse waves to the outside of the machine and receives the waves reflected outside the machine. In addition, based on at least the received wave signal R in the transmitter / receiver 101, the length of the loosened portion Xa in the ground (section length l M ) is provided.

[0102] PC107 is the measurement time (t) and the propagation speed C of the pulse wave propagating through the excavated soil. M Based on this, the distance to the underground pile X outside the earth pressure shield excavator 1 is calculated with high accuracy. Note that the measurement time (t) is the time from when the pulse wave is transmitted until when it is received as a reflected wave.

[0103] In other words, PC107 determines the length of the loosened portion Xa (section length l M ) can be calculated, and the size of the loosened portion Xa can be grasped. Therefore, it is possible to evaluate whether there are any signs of ground collapse.

[0104] Furthermore, since the transmitter / receiver 101 is installed inside the mud pressure shield excavator 1, even after it has started moving, it is possible to flexibly respond to maintenance such as inspection and replacement of the transmitter / receiver 101, and changes to the installation position of the transmitter / receiver 101.

[0105] Furthermore, with the above-described configuration, no special structure is required for measurements by the transmitter / receiver 101 or for mounting the transmitter / receiver 101, and the length of the loosened portion Xa to the underground natural ground X outside the mud pressure shield excavator 1 (section length l M ) can be calculated. Examples of special structures include windows or holes for allowing the transmitter / receiver 101 to come into direct contact with the excavated soil or the natural ground X, or waterproof structures for these, and further, incorporating a waveguide material of a different material into the skin plate 21 or the partition wall 22 in order to improve the transmission efficiency of sound waves.

[0106] In addition, in order to transmit and receive pulse waves as sound waves, the transmitter / receiver 101 transmits and receives pulse waves, and the length of the loosened portion Xa (section length l M ) can be calculated with high accuracy. In addition, the propagation velocity C in the excavated soil excavated by the mud pressure shield excavator 1 M Since the calculation is performed using the length of the loosened portion Xa (section length l M ) can be calculated more accurately.

[0107] In detail, the propagation speed C of the pulse wave propagating through the excavated soil during construction is M Based on this, the length of the loosened portion Xa (section length l M ), it is possible to perform calculations with higher accuracy than when calculations are performed based on a preset propagation speed.

[0108] In addition, in order to make it easier for the pulse wave to propagate through the skin plate 21 and the partition wall 22, the transceiver 101 is attached in close contact with the skin plate 21 and the partition wall 22, so the length of the loosened portion Xa (section length l M ) can be calculated reliably with high accuracy.

[0109] More specifically, by attaching the transceiver 101 in close contact with the skin plate 21 or the partition wall 22, the pulse waves transmitted and received by the transceiver 101 can be easily propagated through the skin plate 21 or the partition wall 22. Therefore, for example, problems such as gaps occurring between the transceiver 101 and the skin plate 21 or the partition wall 22 can be prevented, and the length of the loosened portion Xa (section length l M ) can be calculated reliably with high accuracy.

[0110] In correspondence between the configuration of this invention and the above-mentioned embodiment, the shield tunneling machine of this invention corresponds to the mud pressure shield tunneling machine 1, Similarly, The fuselage corresponds to the front fuselage 20, The outer shell is compatible with skin plate 21, The partition corresponds to partition 22, The transceiver corresponds to transceiver 101, The received information corresponds to the received wave signal R, The excavation range corresponds to the loosened part Xa. The calculator corresponds to the personal computer 107 (PC107), The unexcavated area corresponds to the natural ground X. The exploration system corresponds to the exploration system 100, The memory section is compatible with PC107. The transmission path corresponds to the transmission path 106; The amplifier corresponds to the preamplifier 102. The attenuator corresponds to the attenuator 104, but the present invention is not limited to the configuration of the above-described embodiment, and many other embodiments can be obtained.

[0111] For example, in the above explanation, a transceiver 101 was used that has a transmitting function for transmitting pulse waves outside the aircraft and a receiving function for receiving reflected waves reflected outside the aircraft, but it may also be configured as a separate unit attached to the skin plate 21 or the bulkhead 22, with a transmitter that transmits pulse waves outside the aircraft and a receiver that receives reflected waves reflected outside the aircraft.

[0112] The propagation velocity C of the pulse wave propagating through the excavated soil inside the chamber 40 Mwas calculated using PC107, but the length of the loosened part Xa (section length l M ), aside from PC107, the propagation velocity C M A PC (computer) may be provided to calculate the following.

[0113] In the above description, the exploration system 100 is configured with a plurality of transceivers 101, and the separately configured preamplifiers 102, multiplexer 103, attenuator 104, pulser receiver 105, and personal computer 107. However, the preamplifiers 102, multiplexer 103, attenuator 104, pulser receiver 105, and personal computer 107 of the exploration system 100 may be configured as an integrated unit. Furthermore, the preamplifiers 102, multiplexer 103, attenuator 104, and pulser receiver 105 of the exploration system 100 may be configured as an integrated unit.

[0114] In the above description, three pulse waves are transmitted in step s1, and four pulse waves are transmitted by changing the wave number in step s9 to obtain a data set, but it is also possible to transmit four pulse waves in step s1, and three pulse waves are transmitted by changing the wave number in step s9.

[0115] Furthermore, in steps s1 and s9, pulse waves of a predetermined wave number are transmitted in a frequency band of 80 kHz to 100 kHz, with the frequency changed in 1 kHz increments, but the above frequency band and frequency pitch are not limited to the above numerical values ​​and can be set appropriately. [Explanation of symbols]

[0116] 1... Mud pressure shield excavator 20...Front body 21...Skin Plate 100...Exploration System 101...Transmitter / Receiver 102...Preamp 104...Attenuator 106...Transmission line 107...Personal Computer (PC) R...Received signal X...Natural ground Xa...Loose part

Claims

1. An exploration system comprising a transceiver attached to the inside of a steel member constituting the outer shell or bulkhead in the body of a shield excavator, which transmits sound waves outside the machine and receives the waves reflected outside the machine, and a calculator which calculates the excavation range underground based on at least the information received by the transceiver, and the calculator calculates the distance to an unexcavated area underground outside the machine of the shield excavator, The transceiver comprises: A configuration in which pulse waves at predetermined frequency intervals are sequentially transmitted as the sound waves in a predetermined frequency band, The transceiver comprises: The pulse wave is transmitted in succession at a predetermined frequency pitch. Exploration system.

2. The transmitter / receiver transmits a plurality of pulse waves at a predetermined frequency pitch over an entire predetermined frequency band, The transmitter / receiver further transmits the pulse waves at a predetermined frequency pitch over an entire range of a predetermined frequency band by a number of waves different from the number of waves of the plurality of waves. The exploration system of claim 1 .

3. a storage unit is provided that stores the reception information, which is a result of the transmitter / receiver transmitting the sound wave toward the outside of the aircraft and receiving the reflected wave reflected outside the aircraft; the transceiver sequentially transmits pulse waves at a predetermined frequency pitch as the sound waves in a predetermined frequency band, and stores the reception information at the frequency pitch at which the reflected waves are received as individual data in the storage unit; The computing unit The individual data for each frequency pitch having different wave numbers across the entire range of the predetermined frequency band is set as a data set, and specific data is generated based on the data set; The specific data of the different data set is compared with the generated specific data, and a difference between the specific data of the different data set and the generated specific data is extracted. The exploration system according to claim 1 or 2.

4. a transmission path is provided for transmitting the received information from the transceiver to the storage unit; The transceiver is provided with an amplifier for amplifying the received information, The transmission path for transmitting the received information to the storage unit an attenuator for attenuating the received information amplified by the amplifier and transmitted through the transmission path; The exploration system of claim 3 .

5. The detection system according to any one of claims 1 to 4, wherein the transmitter / receiver is attached to the inside of the steel member. Shield excavator.

6. An exploration method in which sound waves are transmitted from a transmitter / receiver attached to the inside of a steel member constituting an outer shell or a bulkhead in the body of a shield excavator toward the outside of the machine, and a reflected wave reflected outside the machine is received, and the distance to an unexcavated area underground outside the machine of the shield excavator is calculated, Transmitting pulse waves at predetermined frequency intervals in a predetermined frequency band as the sound waves, The pulse waves are transmitted in succession at a predetermined frequency pitch. Exploration methods.

7. A plurality of pulse waves are transmitted at a predetermined frequency pitch over an entire predetermined frequency band, and The pulse waves at each predetermined frequency pitch are further transmitted over the entire range of a predetermined frequency band by a number of waves different from the number of waves of the plurality of waves. The exploration method according to claim 6.

8. the transceiver transmits sound waves toward the outside of the aircraft, and stores reception information resulting from receiving the reflected waves reflected outside the aircraft in a storage unit that stores reception information resulting from the reception of the reflected waves reflected outside the aircraft, the transceiver sequentially transmits pulse waves at predetermined frequency intervals as the sound waves in a predetermined frequency band, and stores the reception information for each frequency interval at which the reflected waves are received as individual data; The calculator is The individual data for each frequency pitch having different wave numbers across the entire range of the predetermined frequency band is set as a data set, specific data is generated based on the data set, and The specific data of the different data set is compared with the generated specific data, and a difference between the specific data of the different data set and the generated specific data is extracted. The exploration method according to claim 6 or 7.

9. a transmission path is provided for transmitting the received information from the transceiver to the storage unit; The transceiver amplifies the received information, The received information transmitted through the transmission path is attenuated and stored in the storage unit. The exploration method according to claim 8.

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