JP2710740B2 - Front face exploration method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a front face exploration method for exploring a stratum in front of a face as an excavation surface when a space such as a tunnel is formed underground.

[0002]

2. Description of the Related Art In excavation of a tunnel, it is necessary to surely grasp the geology in front of a face, which is an excavation surface, and to take countermeasures for safe and reliable construction.

[0003] As a conventional search method for examining the front of such a face, there has been a method of making a prediction based on a result of geological observation at a tunnel wall face, and conducting a survey by advanced boring as necessary. According to this advanced boring, the core of the stratum to be checked can be reliably collected, so that the stratum in front of the face can be directly visually observed.

[0004] Other conventional search methods include:
Rayleigh wave probing is known. The Rayleigh wave exploration method is described in, for example, the 46th Annual Scientific Lecture
(September, 1989) disclosed on pages 194 and 195 of the document, in which a vibrator is attached to a face and vibrated while changing the frequency of the Rayleigh wave to obtain data in the course direction. . It is possible to detect a fault crushed body 20 m ahead of the face.

[0005]

However, in the conventional exploration system for performing the above-mentioned advanced boring, it is necessary to stop the advancement of the cutting face or to excavate the horizontal shaft when performing the preceding boring. , Which put pressure on construction costs and hindered the progress of construction.

In the above-mentioned Rayleigh wave exploration method, the exploration distance in front of the face is about several to 20 m, the exploration distance is short, and it is necessary to attach a large exciter to the face. There was a problem that caused trouble.

Therefore, the present invention has been made in view of the above points, and has as its object the purpose of which is to provide a long exploration distance, facilitate two-dimensional or three-dimensional exploration, and improve the progress of construction. An object of the present invention is to provide a front face exploration method that does not cause any trouble.

[0008]

In order to solve the above-mentioned problems, a front face exploration system according to the present invention comprises: a drill for drilling while moving a tip position with respect to a front of a face;
A plurality of geophones that are arranged with a two-dimensional spread on the surface of the face and detect a vibration wave generated by a bit portion at the tip of the drill;
Analyzing means for analyzing a vibration wave between the bit portion and the surface of the face detected by the plurality of geophones while moving the blade in front of the blade; and a formation in front of the face based on an analysis result by the analyzing means. And geological discriminating means for analyzing the properties or structure of the object, and output means for outputting an analysis result by the analyzing means.

[0009]

In the front face exploration method of the present invention, the vibration generated by the bit portion at the tip of the drilling hole is detected by a plurality of geophones attached two-dimensionally to the surface of the face. Then, the detected vibration wave is analyzed by the analyzing means, and the geological judging means judges the properties and structure of the stratum based on the analysis result.

[0010] In particular, the vibration generated by the drilling drill includes a continuous vibration wave generated when a rock or the like is crushed by the bit at the tip at the time of drilling, and a bit at the tip at the bottom when the drilling is temporarily stopped. There is a pulse-like vibration wave generated when hitting the ground, and by analyzing one or both of them, the ground condition and physical property values, that is, the properties or structure of the stratum can be accurately determined. .

In the present invention, a vibration wave necessary for analysis is generated by using a drill, and a general drill used for a blasting method or the like can also be used for generating vibration. In particular, there is no need to attach a large exciter to the face, and there is no hindrance to the progress of the construction.

Further, since a general drill is used, if a rod is added, the drilling depth becomes several tens of meters.
To several hundred meters, and the search distance can be lengthened. Furthermore, since the vibration wave generated by the bit portion at the tip of the drilling hole is detected by the geophone arranged with a two-dimensional spread, three-dimensional exploration can be easily performed.

[0013]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of an embodiment of a search system according to the present invention;

A feature of the exploration system of the present embodiment is that a continuous vibration wave generated when drilling a face with a hydraulic drill is detected by a geophone attached to the face and analyzed. Another feature is that this drilling is paused,
The point is that a single-pulse vibration wave generated when the bottom of the hole is hit by the tip of the bit of the hydraulic drill is detected by a geophone attached to the face and analyzed. Therefore, the frontal exploration of the face is performed using the vibration waves generated by these two types of vibration waves. Hereinafter, the details and configuration and operation of the search system of the present embodiment will be described separately.

(1) Configuration of the Search System FIG. 1 is a diagram showing the overall configuration of the search system of the present embodiment.

In FIG. 1, each of a plurality of geophones 10 detects a vibration wave propagated from the inside of the stratum in front of the face 60 to the surface of the face. For example, a geofont that detects vibration by using an electromotive force generated by a relative movement of a coil suspended by a spring in a magnetic field created by a fixed magnet is used. Most of the plurality of geophones 10 are distributed over the entire surface of the face 60, and one of them is attached to the hydraulic drill 12.

The collected data storage unit 20 includes a plurality of geophones 1
The vibration waves detected and received in each of the zeros are collected and accumulated for each of the vibration receivers 10. The data stored in the collected data storage unit 20 may be either digital or analog, but in this embodiment, it is assumed that the data is converted into digital data and stored. For this reason, the exploration system of the present embodiment has an analog-digital (A / D) converter 22 at a stage preceding the collected data storage unit 20.
The output (analog data) of each geophone 10 is converted into digital data by the A / D converter 22, and the converted digital data is stored in the collected data storage unit 20.

When collecting (accumulating) the vibration waves detected by the respective geophones 10 in an analog form, an A / D converter 22 is connected to a stage subsequent to the collected data storage unit 20.

The spectrum analysis unit 24 includes the hydraulic drill 12
When drilling is performed, a continuous wave (continuous drilling wave) generated by the bit tip 14 breaking the rock is analyzed. By performing this spectrum analysis, the time delay and attenuation of the continuous drilling wave propagating in front of the face can be determined for each frequency component, and the estimation of the ground condition and physical properties can be performed two-dimensionally and three-dimensionally. it can.

Similarly, the geotomography analysis unit 26
Is to perform an analysis by geotomography based on an elastic wave generated when the bit tip 14 of the hydraulic drill 12 is hit against the bottom of the hole. By performing this geotomography analysis, the two-dimensional and three-dimensional structures (geological sectional structure, physical property distribution, etc.) in front of the face can be known.

The analysis result storage unit 28 is for temporarily storing analysis results of the spectrum analysis unit 24 and the geotomography analysis unit 26. Each of these analyzes
This is performed when the position of the bit tip 14 of the hydraulic drill 12 reaches a predetermined position from the face 60. The position of the bit tip 14 for performing each of these analyzes is at a predetermined interval (for example, 1 m interval).
Is set to Then, the analysis results corresponding to the bit tip positions at these predetermined intervals are stored in the analysis result storage unit 28.

The geological determination unit 30 determines the nature and structure of the geology based on the analysis result stored in the analysis result storage unit 28. In addition, the comparison data storage unit 32 stores a spectrum analysis result and a geotomography analysis result for a known geology in advance.

The geological discriminating unit 30 compares the analysis result of the known stratum stored in the comparison data storage unit 32 with each analysis result obtained by actual exploration stored in the analysis result storage unit 28. By comparing, the geology in front of the face 60 is determined.

The display unit 34 is for displaying the result of the determination by the geological determination unit 30, and includes, for example, a CRT (cathode ray tube) and its display control unit. The display unit 34 can also display the analysis results of the spectrum analysis unit 24 and the geotomography analysis unit 26 in real time.

The printer 36 is for outputting the result of the determination by the geological determination unit 30 to a recording sheet. As with the display unit 34, the printer 36 performs the analysis results of the spectrum analysis unit 24 and the geotomography analysis unit 26. Can also be output in real time.

The search control unit 40 controls the overall operation of the above-described search system. In particular, the collected data storage unit 20, the spectrum analysis unit 24, the geotomography analysis unit 26, the analysis result storage unit 28, the geological determination unit 38 is controlled. That is, when predetermined vibration wave data is read from the collected data storage unit 20, the spectrum analysis unit 24 and the geotomography analysis unit 2
6 and the analysis results are stored in the analysis result storage unit 28 when the analysis is completed. Also,
When all the analyzes are completed, all the analysis results are read from the analysis result storage unit 28, and the timing control is performed so that the geological determination unit 30 performs the determination process.

In each processing by the spectrum analysis unit 24, the geotomography analysis unit 26, and the geological determination unit 30, it is necessary to use the position data of the bit tip 14 of the hydraulic drill 12 as a parameter for analysis or determination. The position data is input to the search control unit 40 from the hydraulic drill drive control unit 50 described later and is created by the search control unit 36 based on the other bit position information, and the spectrum analysis unit 24, the geotomography analysis unit 26, the geological determination unit 2
8 has been entered.

The hydraulic drill drive control unit 50 controls the drilling operation by the hydraulic drill 12, and can freely set the drilling speed and drilling length. The controlled drilling length is input to the search control unit 40 as bit position information.

The hydraulic drill drive control unit 50 also controls vibration waves generated by the hydraulic drill 12. That is, when a continuous drilling wave is generated, the hydraulic drill drive control unit 50 performs control to rotate and propel the hydraulic drill 12. On the other hand, in order to generate a pulse-like elastic wave, the hydraulic drill drive control unit 50
By temporarily stopping the rotation and propulsion of the hydraulic drill 12 and reciprocating the entire hydraulic drill 12, control is performed to strike the bit tip 14 against the bottom of the hole.

FIG. 2 is a diagram showing the installation positions of the plurality of vibration receivers 10 and the drilling positions by the hydraulic drill 12 on the surface of the face 60.

FIG. 3A shows an example in which the geophones 10 are installed on a cross line. Seven geophones 10 are arranged on a horizontal line, and three geophones are arranged on a vertical line intersecting the geophone. A geophone 10 is arranged. Further, a total of four drilling positions are arranged at both ends of the horizontal line and the upper end of the vertical line, and at the intersection of the two lines, and the drilling positions are shown in FIGS. The same applies to the case.

FIG. 2B shows an example in which the geophone 10 is installed on the circumference, and nine geophones 1 are arranged on the circumference.
0 is arranged. In FIG. 6C, in addition to the position shown in FIG. 6B, five geophones 10 are further disposed inside.

FIG. 3 is a view showing a schematic structure of a rock drill having the above-mentioned hydraulic drill 12. As shown in FIG. This rock drill has a structure in which the rock drill having the hydraulic drill 12 and the vehicle for movement are integrated, and when the position of the face 60 advances due to the progress of the drilling, the hydraulic drill 12 can be easily mounted. The position can be changed. Hydraulic drill 1
2, the drilling is performed on the face 60. The drilling length is determined by adding several rods to several
00 m.

(2) Searching operation by the search system Next, an operation when a forward search is performed using the search system of this embodiment will be described.

The exploration system of the present embodiment discriminates geology and its structure using two types of vibration waves as described above. FIG. 4 is a view schematically showing a case where a continuous drilling wave is generated. As shown in the figure, drilling is performed by a hydraulic drill 12 attached to a rock drill, but the details of the drilling are no different from drilling performed by a general blasting method or the like. Therefore, the hydraulic drill 12 used in ordinary tunnel construction can be used as it is. In a general blasting method or the like, the drilling distance is about several meters. Therefore, when drilling from several tens of meters to several hundreds of meters as in this embodiment, the bit length is determined according to the drilling distance. Need to be added.

FIG. 5 is a view schematically showing a case where the bottom of the hole is hit with the bit tip 14 of the hydraulic drill 12 to generate a pulse-like elastic wave. In order to generate such elastic waves, drilling by the hydraulic drill 12 is temporarily stopped, and the bottom of the drilled hole is hit by the bit tip 14 of the hydraulic drill 12 that has stopped rotating. Thereafter, drilling is resumed, and after the position of the bit tip 14 has advanced a predetermined distance,
The drilling is temporarily stopped again to generate an elastic wave. In this way, by stopping drilling at predetermined intervals and hitting the bottom of the hole, pulse-like elastic waves are generated at predetermined intervals.

Next, a detailed operation in the case of performing a forward search of the face 60 by the search system of this embodiment will be described.
FIG. 6 is a diagram showing the operation procedure, and each step in FIG. 6 will be described below.

Step 600 (Drilling): First, the survey system starts drilling a predetermined position of the face 60 (for example, a position near the center in FIG. 2A). Specifically, the hydraulic drill 12 is rotated, vibrated, and propelled under the control of the hydraulic drill drive control unit 50, and the bit tip 14 is rotated.
Drilling is performed by shaving the rock.

Step 601 (reception of continuous drilling wave, etc.):
Next, the search control unit 40 sends an instruction to the collected data storage unit 20 to accumulate data of the vibration waves detected by the respective geophones 10. The geophones 10 distributed on the entire face of the face 60 and the geophones 10 attached to the hydraulic drill 12
Is output to the collected data storage unit 20 via the A / D converter 22, and the collected data storage unit 20 stores the vibration waves based on the storage instruction from the search control unit 40. Stores data to be output from.

Step 602 (detection of bit tip position): Next, the position of the bit tip 14 of the hydraulic drill 12 is detected. This position detection is performed by the hydraulic drill drive control unit 5
This is performed based on the bit position information sent from 0 to the search control unit 40.

Step 603 (determination of search position): Next, it is determined whether or not the bit tip 14 of the hydraulic drill 12 has reached the search position. The search position is determined by the search control unit 40 based on the bit position information input from the hydraulic drill drive control unit 50. If the search position has not been reached, the process returns to step 600 to perform the drilling operation. continue. When the position of the bit tip 14 reaches the search position, the search control unit 40 makes an affirmative determination in the determination processing in step 602.

In the above description, the search control unit 40 performs the determination processing of step 603 based on the bit position information input from the hydraulic drill drive control unit 50, and automatically stores it in the collected data storage unit 20. Although an instruction is sent, a worker is provided with a display unit (not shown) connected to the hydraulic drill drive control unit 50 or the search control unit 40.
May be monitored, and the determination in Step 603 may be visually performed. In this case, when the bit tip 14 reaches the predetermined position, the operator sends an instruction to the search control unit 40, and the search control unit 40 issues a storage instruction to the collected data storage unit 20 in response to the instruction. Will be sent.

Step 604 (stop drilling): Next, the hydraulic drill drive control unit 50 suspends rotation and propulsion of the hydraulic drill 12 and stops drilling operation. This stopping process may be performed by the judgment of the hydraulic drill drive control unit 50 itself, or the search control unit 40 may send a stop instruction to the hydraulic drill drive control unit 50. After the operator confirms that the data storage in the collected data storage unit 20 has been completed, the operator may operate the hydraulic drill drive control unit 50 to stop the drilling operation.

Step 605 (pulse-like elastic wave generation): Next, a pulse-like elastic wave is generated. The generation of the elastic wave is performed by hitting the bit tip 14 of the hydraulic drill 12 to the hole bottom drilled in step 600 under the control of the hydraulic drill drive control unit 50.

Step 606 (accumulation of elastic waves):
An instruction is sent from the search control unit 40 to the collected data storage unit 20, and the collected data storage unit 20 stores an output signal based on the pulsed elastic wave received by each of the geophones 10. This storage processing is substantially the same as the processing in step 601 described above.

Step 607 (reading of collected data):
Next, the search control unit 40 reads the data stored in the collected data storage unit 20. The collected data storage unit 20 stores the collected data for the continuous drilling wave stored in step 601 and the collected data corresponding to the pulsed elastic wave stored in step 606. The data for the drilling wave is read from the collected data storage unit 20 and then input to the spectrum analysis unit 24. On the other hand, data corresponding to the pulsed elastic wave is read from the collected data storage unit 20 and then input to the geotomography analysis unit 26.

Step 608 (Spectrum, Geotomography Analysis): Next, the spectrum analysis unit 24 performs a spectrum analysis based on the data read from the collected data storage unit 20 and input. Similarly, the geotomography analysis unit 26 performs a geotomography analysis based on the data read and input from the collected data storage unit 20.

FIG. 7 is an explanatory diagram showing an outline of the spectrum analysis. FIG. 3A shows a vibration waveform of a continuous drilling wave received by each of the geophones 10. 1 to n correspond to the respective geophones 10.
The vibration wave data is read from the collected data storage unit 20 and input to the spectrum analysis unit 24. Since the distance between the bit tip 14 and each geophone 10 is different for each geophone, the continuous drilling wave detected by each geophone 10 also has a time delay according to the position of each geophone 10. FIG. 2B shows the result of the spectrum analysis by the spectrum analysis unit 24, in which the spectrum analysis is performed on the vibration waveform of each channel in FIG.

Similarly, FIG. 8 is an explanatory diagram showing an outline of the geotomography analysis. In the figure, the waveform data of channel 0 (ch. 0) corresponds to the geophone 10 attached to the hydraulic drill 12 and indicates the point in time when a pulse-like elastic wave is generated by the bit tip 14. . Waveforms of the other channels (ch. 1 to n) are distributed to the other geophones 10 distributed on the face 60.
, And each of the geophones 1
A time delay corresponding to the distance between zeros occurs. Therefore, geotomography analysis is performed based on the time delays t1, t2, t3,... For each channel, the amount of attenuation of each waveform, and the like.

In this embodiment, the hydraulic drill 12
When the time point of generation of a pulse-like elastic wave is confirmed by the geophone 10 attached to the hydraulic drill 12, the time lag of vibration generation occurs due to the positional deviation between the geophone 10 attached to the hydraulic drill 12 and the bit tip 14 In this case, it is necessary to measure this time lag beforehand and to perform correction at the time of geotomography analysis. In addition, the hydraulic drill 12 has
In addition to the method of attaching the hydraulic drill drive control unit 50
, A time delay from when a drilling instruction is sent to the hydraulic drill 12 to when vibration is generated by the bit tip 14 is measured in advance, and a pulse is generated based on the drilling instruction output from the hydraulic drill drive control unit 50. You may make it specify the generation | occurrence | production point of the shape-like elastic wave.

Step 609 (storage of analysis results): After the analysis is performed by the spectrum analysis unit 24 and the geotomography analysis unit 26 in this manner, the analysis result storage unit 28 stores these analysis results. .

Step 610 (judgment of completion of data collection / analysis): Next, the search control unit 40 collects and stores data from each of the geophones 10 in the collected data storage unit 20, and the spectrum analysis unit 24, the geotomography analysis unit 26
It is determined whether or not all the analyzes by have been completed. If not completed, that is, if the drilling by the hydraulic drill 12 is to be continued to collect and analyze data, a negative determination is made, and the process returns to step 600 to repeat the drilling operation. For example, a hole with a depth of 100 m is made, and
When collecting and analyzing data at intervals, a negative determination is made in this step 610 until the depth reaches 100 m, and the drilling operation is continued.

Step 611 (Geological discrimination): When all data collection and analysis are completed, the investigation control unit 40 makes an affirmative judgment in the judgment processing of Step 610, and instructs the geological judgment unit 30 to start the judgment processing. . In response to this instruction, the geological determination 30 determines the geology in front of the face 60 based on the analysis result already stored in the analysis result storage unit 28. The geological discrimination includes a property discrimination for discriminating a type of rock constituting the geology and a structure discrimination for discriminating a fault or the like in the stratum. Each determination is made by comparing the known geological data stored in the comparison data storage unit 32 with the analysis result read from the analysis result storage unit 28.

Step 612 (display and output of result): When the discrimination processing by the geological discrimination unit 30 is completed, the discrimination result is displayed in the one-dimensional, two-dimensional or three-dimensional form on the display unit 34.
Is displayed on the display screen. Alternatively, the data is output from the printer 36 as needed.

The display unit 34 and the printer 36
In addition to the results of the geological discrimination, the progress of the geological discrimination and the results of the analysis by the spectrum analysis unit 24 and the geotomography analysis unit 26 are displayed and output each time. Exploration can be performed.

As described above, according to the front face exploration system of the present embodiment, the vibration wave necessary for the front exploration is generated by using the hydraulic drill 12 used in the normal blasting method or the like. There is no need to specially install the vibration source used. Therefore, it is not necessary to retract all of the normal excavation equipment from the face when performing forward exploration, and there is no hindrance to the progress of the tunnel construction.

Further, a general hydraulic drill 12 used for a blasting method or the like can extend the drilling depth from several tens of meters to several hundreds of meters by adding rods. The exploration depth by the forensic exploration system is also possible between tens of meters and hundreds of meters. This is a sufficient length even when compared to the conventional depth of about 20 m, which is the exploration depth by the Rayleigh wave.

Further, in the present embodiment, the plurality of vibration receivers 10 used for detecting the vibration wave are provided with a face 60 as shown in FIG.
Are distributed and arranged two-dimensionally on the entire surface, so that the bit tip 14 as a vibration source and each of the geophones 10 are three-dimensionally connected. Therefore, the search by the search system of the present embodiment can be easily extended to a three-dimensional search.

The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention.

For example, in this embodiment, the case where the spectrum analysis is performed using the continuous drilling wave and the geotomography analysis is performed using the pulsed elastic wave has been described as an example. It is not always necessary to use the analysis using the pulsed elastic wave and only one of them may be used. In addition, the analysis method is not limited to the spectrum analysis and the geotomography analysis, and any other analysis method useful for geological discrimination may be used. Other analysis methods include:
There is a cross spectrum method or the like in which only a specific mode is extracted from a continuous drilling wave in which various propagation modes are superimposed to determine a time difference of arrival.

In this embodiment, the hydraulic drill 1
Although the drilling is performed by the method 2, the drilling may be performed by a mechanical drill.

In this embodiment, when the drilling is performed by the hydraulic drill 12, data is collected and analyzed at intervals of 1 m, and the geology is determined based on all the analysis results. However, data analysis and geological discrimination may be performed for each excavation depth.

Further, in this embodiment, a cycle of continuously collecting data on continuous drilling waves, collecting data on pulsed elastic waves at predetermined intervals, and then analyzing the collected data is repeated. In the end, geological discrimination was performed based on the results of these analyses, but the order of data collection and analysis is not limited to this.
You may make it perform simultaneously. For example, the spectrum analysis and the geotomography analysis in step 608 of FIG. 6 may be performed after all data collection is completed, that is, after a positive determination is made in step 610. In addition, the spectrum analysis is performed in parallel with the collection and accumulation of the continuous drilling wave data in step 601, and when the bit tip of the drilling drill passes through a fault or the like, the spectrum analysis result obtained in parallel is referred to. This may be used to determine this tomography or the like in real time.

[0064]

As described above, according to the present invention, a vibration wave necessary for analysis is generated using a drill.
A general drill used for the blasting method or the like can also be used for generating vibration, and there is no need to particularly mount a vibration source in a boring hole, which does not hinder the progress of construction.

Further, since a general drill is used, if a rod is added, the drill depth becomes several tens.
m to several hundred meters, and the search distance can be extended.

Further, since the vibration wave generated by the bit portion at the tip of the drilling hole is detected by the geophone arranged with a two-dimensional spread, three-dimensional geological exploration can be easily performed. .

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an overall configuration of a search system according to an embodiment.

FIG. 2 is a diagram showing the installation positions of a plurality of geophones and the drilling positions of a hydraulic drill on the face of the face.

FIG. 3 is a diagram showing a schematic structure of a rock drill having a hydraulic drill.

FIG. 4 is a view schematically showing a case where a continuous drilling wave is generated.

FIG. 5 is a diagram schematically showing a case where a pulse-like elastic wave is generated.

FIG. 6 is a diagram illustrating an operation procedure of the search system of the present embodiment.

FIG. 7 is a diagram showing an outline of spectrum analysis data.

FIG. 8 is a diagram showing an outline of geotomography analysis data.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Geophone 12 Hydraulic drill 14 Bit tip 20 Collection data storage part 24 Spectrum analysis part 26 Geotomography analysis part 28 Analysis result storage part 30 Geological discrimination part 32 Comparison data storage part 40 Search control part 50 Hydraulic drill drive control part

Continuation of the front page (72) Inventor Masafumi Naito 1-7-1, Kyobashi, Chuo-ku, Tokyo Toda Construction Co., Ltd. (56) References JP-A 1-223289 (JP, A) JP-A 63-32085 (JP, A) JP-A-62-101800 (JP, A) JP-A-3-28494 (JP, A)

Claims (4)

(57) [Claims] 1. Do not move the tip position with respect to the front of the face.
And a plurality of geophones that are arranged with a two-dimensional spread on the surface of the face and detect a vibration wave generated by a bit portion at the tip of the drill, While moving the tip position in front of the face
The bit portion detected by the plurality of geophones ;
Analysis means for analyzing the vibration wave between the face and the surface, geological discrimination means for analyzing the properties or structure of the stratum in front of the face based on the analysis results by the analysis means, and analysis results by the analysis means Output means for outputting, and a front face exploration method for a face. 2. The front face exploration method according to claim 1, wherein the vibration wave detected by the geophone is a vibration wave generated by a bit portion at the tip of the drill during drilling. 3. The vibration wave according to claim 1, wherein the vibration wave detected by the geophone is a vibration wave generated by stopping drilling by the drill and hitting a bit portion at a tip. The front face exploration method. 4. The analysis result storage unit according to claim 1, wherein the geological determination means sequentially stores analysis results obtained by the analysis means obtained when a tip position of the drilling drill is changed at predetermined intervals. A comparison data storage unit that stores the analysis result of the formation as comparison data, and the analysis result stored in the analysis result storage unit is input,
A discriminator for analyzing the properties or structure of the stratum between the tip of the drill and the cutting face based on the comparison data stored in the comparison data storage section.