JP2010180605A - Device and program for evaluation of foundation ground condition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a device and a program for evaluation of a foundation ground condition, which can accurately evaluate a foundation ground condition at low cost before excavating work. <P>SOLUTION: Such an evaluation is made that the more an attenuation amount of vibration amplitude measured by a second accelerograph 16 at the surface of the ground relative to vibration amplitude measured by a first accelerograph 14 at the leader part 32 of a ground drilling machine 30 is, the more cracks exist in the ground when the ground to be evaluated is drilled by the ground drilling machine 30. The information for the evaluation result is displayed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a ground condition evaluation apparatus and program, and more particularly, to a ground condition evaluation apparatus and program for evaluating a ground condition using a ground drilling machine.

  Conventionally, when performing excavation work of the ground, a mountain retaining wall is often constructed with a main pile lateral sheet pile and a ground anchor is used as a supporting work. And when designing the said retaining ring, it is necessary to consider the ground conditions, such as the hardness of the ground used as construction object, and the quantity of a crack.

  For this reason, it is necessary to grasp the condition of the ground that is subject to excavation work, but in order to investigate the condition of the ground with large variations by means of a boring survey, a large amount of boring is necessary, which is expensive. In general, it is generally understood based on the amount of displacement of the retaining wall at the stage of excavation work or by visual observation of the ground.

  As described above, conventionally, it has been difficult to grasp the condition of the ground until the excavation work is performed from the viewpoint of cost, so a technology that can evaluate the condition of the ground at an early stage while suppressing the generation of expenses is eagerly desired. It was.

  As a conventional technique that can be applied for this purpose, Patent Document 1 discloses an investigation device for estimating, visualizing, and controlling work of a drilling surface excavated by a tunnel boring machine. An accelerometer attached to a number of cutter pedestals held by the cutter head to support the accelerometer, a rotation angle detector attached to the cutter head to detect the position of the accelerometer, Estimate and display the geological classification of the excavation surface based on the analyzer that calculates the average value of the frequency and amplitude from the measured values, and the dominant frequency and the vibration correction value obtained during at least one rotation of the cutter head. A technology having an information transmission display device is disclosed.

  Patent Document 2 discloses energy calculation means for calculating propulsive energy, rotational energy, and impact energy acting on a drilling portion of a drilling device during ground drilling based on sensor detection parameters, and survey cutting. Based on the propulsive energy obtained at the time of drilling, the rotational energy, and the correlation between the striking energy and the depth / column diagram data, the discriminant reference setting means for setting the discriminant reference for the ground rock mass, and obtained at the time of actual drilling There is disclosed a technique having a discriminating means for discriminating a formation rock in a drilling hole in real time based on a comparison result between the propulsive force energy, the rotational energy, and the impact energy and the discrimination criterion.

  Furthermore, in Patent Document 3, when excavating or drilling the ground, an acoustic sensor or an acceleration sensor is attached in the vicinity of the bit to continuously measure the waveform of excavation sound or vibration generated during excavation or drilling. A technique is disclosed in which an amplitude distribution is obtained for each unit time or unit depth based on the obtained waveform, and analysis of geology and formation change is performed.

JP-A-9-170398 JP 2004-92063 A JP 2000-337070 A

  However, in the techniques disclosed in Patent Documents 1 to 3, a sensor for detecting a physical quantity used for evaluation of the state of the ground is provided only on the machine side that performs excavation, drilling, and the like. As a result of detecting the physical quantity affected by only a part of the crack generated in the target ground, there is a problem that the ground state cannot always be evaluated with high accuracy.

  The present invention has been made to solve the above problems, and provides a ground condition evaluation apparatus and program capable of evaluating the condition of the ground with high accuracy and low cost at an earlier stage than excavation work. With the goal.

  In order to achieve the above object, a ground condition evaluation apparatus according to claim 1 is provided in a ground drilling machine for drilling a ground to be evaluated, and measures the amplitude of vibration at the provided position to measure the vibration amplitude. A first measuring means for outputting the above signal, a second measuring means for measuring the amplitude of vibration on the surface of the ground and outputting a second signal, and drilling the ground by the ground drilling machine. Receiving means for receiving the first signal output by the first measuring means and the second signal output by the second measuring means, and the first signal received by the receiving means. Evaluation means for evaluating that the more the amount of attenuation of the second amplitude obtained by the second signal with respect to the first amplitude obtained by the above signal is, the more cracks in the ground are, and information indicating the evaluation result by the evaluation means Display means for displaying It is provided.

  According to the ground condition evaluation apparatus of the first aspect, the amplitude of the vibration at the provided position is measured by the first measuring means provided in the ground drilling machine for drilling the ground to be evaluated. While the first signal is output, the amplitude of vibration on the surface of the ground is measured by the second measuring means, and the second signal is output. The first measuring means and the second measuring means include various devices and various sensors that can measure the amplitude of vibration, such as an accelerometer, a speedometer, a displacement meter, an acceleration sensor, a speed sensor, and a displacement sensor. .

  Here, in the present invention, when the ground is drilled by the ground drilling machine, the first signal output by the first measuring means and the second signal output by the second measuring means. The signal is received by the receiving means, and the more the amount of attenuation of the second amplitude obtained by the second signal with respect to the first amplitude obtained by the received first signal, the more cracks in the ground It is evaluated by the evaluation means.

  And in this invention, the information which shows the evaluation result by the said evaluation means is displayed by a display means. In addition, in the display by the display means, in addition to visible display by various display devices such as a liquid crystal display device, a plasma display device, an organic EL display device, and a CRT display device, permanent visible display by an image forming apparatus such as a printer device, An audible display by a voice output device such as a voice synthesizer is included.

  That is, in the present invention, the physical quantity used for the evaluation is measured by the second measuring means provided on the ground surface with respect to the first amplitude measured by the first measuring means provided on the ground drilling machine. In addition, since the attenuation amount of the second amplitude is used, and this attenuation amount is a value that reflects many of the cracks occurring in the ground, compared to the case where the attenuation amount is not used, The condition of the ground can be evaluated with high accuracy.

  In the present invention, the state of the ground can be evaluated at the stage of actual drilling by the ground drilling machine, and the state of the ground can be evaluated at an earlier stage than excavation work. It should be noted that the evaluation of the ground condition according to the present invention can be realized at a lower cost compared to the case where a large number of drilling surveys are performed.

  Thus, according to the ground condition evaluation apparatus according to claim 1, when the ground to be evaluated is drilled by the ground drilling machine, the vibration amplitude measured in the ground drilling machine is measured. As the amount of vibration amplitude attenuation on the ground surface increases, it is evaluated that there are more cracks in the ground, and information indicating the evaluation result is displayed, so the ground can be obtained with high accuracy and low cost at an earlier stage than excavation work. Can be evaluated.

  In addition, although there is no restriction | limiting in particular as an installation position in the ground drilling machine of the said 1st measurement means, since the physical quantity used for evaluation of the state of a ground in this invention is the said attenuation amount, It is preferable to provide it at a position close to the ground, and it is preferable to provide it at the leader part or rod part of the ground drilling machine.

  Further, in this case, information indicating a predetermined amount of crack in the ground is previously stored in the storage unit so as to increase as the attenuation amount increases, and the evaluation unit reads out the information from the storage unit. It is preferable to apply. Here, the storage means includes a RAM (Random Access Memory), an EEPROM (Electrically Erasable and Programmable Read Only Memory), a semiconductor storage element such as a flash EEPROM (Flash EEPROM), smart media (SmartMedia (registered trademark)), A portable recording medium such as a flexible disk or a magneto-optical disk, a fixed recording medium such as a hard disk, or an external storage device provided in a server computer connected to a network is preferably used.

  Further, in the present invention, as in the invention described in claim 2, the evaluation means may evaluate that the degree of softness of the ground is higher as the first amplitude is further decreased. Thereby, compared with the case where it evaluates without using the said 1st amplitude, the state of a ground can be evaluated with higher precision.

  In this case as well, information indicating the degree of softness of the ground determined in advance so that the degree becomes higher as the first amplitude is smaller is stored in advance by the storage unit, and the evaluation unit stores the memory Preferably, the information is read from the means and applied.

  Further, as in the invention described in claim 3, the present invention further comprises a removing means for removing a vibration component of the ground drilling machine itself from the first amplitude and the second amplitude, and the evaluating means However, the attenuation amount may be derived and applied by the first amplitude and the second amplitude from which the vibration component of the ground drilling machine itself has been removed by the removing means. Thereby, as a result of being able to make the said attenuation amount more highly accurate, the state of the ground can be evaluated with higher accuracy.

  Further, the present invention, as in the invention described in claim 4, further comprises a second removal means for removing the influence of the depth of the drilling hole from the attenuation amount, and the evaluation means comprises the second The attenuation amount in which the influence due to the depth of the hole is removed by the removing means may be applied. Thereby, as a result of being able to make the said attenuation amount more highly accurate, the state of the ground can be evaluated with higher accuracy.

  Further, according to the present invention, as in the invention described in claim 5, the evaluation unit may perform the evaluation for each of a plurality of predetermined drilling depth categories for the ground by the ground drilling machine. Good. Thereby, as a result of being able to evaluate the state of the ground for each drilling depth category, the convenience can be further improved.

  Particularly, in the invention described in claim 5, as in the invention described in claim 6, the evaluation means may perform the evaluation based on a relative magnitude relationship between the drilling depth sections. . As a result, relative evaluation on the same ground becomes possible, and as a result, convenience can be further improved.

  On the other hand, in order to achieve the above object, the program according to claim 7, wherein the ground drilling machine when the ground is drilled by the ground drilling machine for drilling the ground to be evaluated An evaluation means for evaluating that the amount of vibration attenuation on the surface of the ground relative to the vibration amplitude of the ground is larger, and a display means for displaying information indicating an evaluation result by the evaluation means. It is for functioning.

  Therefore, according to the program according to claim 7, since it can be made to act on the computer in the same manner as the invention according to claim 1, like the invention according to claim 1, at an earlier stage than excavation work, The condition of the ground can be evaluated with high accuracy and low cost.

  Furthermore, in order to achieve the above object, a program according to claim 8 causes a computer to function as an evaluation unit and a display unit in the ground condition evaluation device according to any one of claims 1 to 6. belongs to.

  Therefore, according to the program of claim 8, since it can be made to act on the computer in the same manner as the ground condition evaluation apparatus of the present invention, as in the ground condition evaluation apparatus, at an earlier stage than excavation work, The condition of the ground can be evaluated with high accuracy and low cost.

  According to the present invention, when the ground to be evaluated is drilled by the ground drilling machine, the attenuation amount of the vibration amplitude on the surface of the ground with respect to the amplitude of the vibration measured in the ground drilling machine is The effect is that it is possible to evaluate the condition of the ground with high accuracy and low cost at an earlier stage than excavation work, because the more it is evaluated, the more cracks of the ground are evaluated and the information indicating the evaluation result is displayed. Is obtained.

It is a block diagram which shows the structure of the ground condition evaluation system which concerns on embodiment. It is a side view which shows the arrangement | positioning position of the principal part of the ground condition evaluation system which concerns on embodiment. It is a block diagram which shows the principal part structure of the electric system of the personal computer which concerns on embodiment. It is a schematic diagram which shows the main memory content of the secondary memory | storage part with which the personal computer which concerns on embodiment was equipped. It is a schematic diagram which shows the data structure of the measurement information database which concerns on embodiment. It is a schematic diagram which shows the data structure of the ground classification information database which concerns on embodiment. It is a wave form diagram which shows an example of the 1st acceleration response memorize | stored in the measurement information database which concerns on embodiment, and a 2nd acceleration response. It is a flowchart which shows the flow of a process of the ground condition evaluation process program which concerns on embodiment. It is a figure with which it uses for description of the processing content of the ground condition evaluation processing program which concerns on embodiment, and is a graph which shows an example of the 1st correction | amendment amplitude for every drilling depth. It is a figure with which it uses for description of the processing content of the ground condition evaluation processing program which concerns on embodiment, and is a graph which shows an example of the attenuation amount for every drilling depth. It is a figure with which it uses for description of the processing content of the ground condition evaluation processing program which concerns on embodiment, and is a graph which shows an example of the correction | amendment attenuation amount for every drilling depth. It is a figure with which it uses for description of the processing content of the ground condition evaluation processing program which concerns on embodiment, and is a graph which shows an example of the average value for every drilling depth division of the 1st correction | amendment amplitude for every drilling depth. It is a figure which uses for description of the processing content of the ground condition evaluation processing program which concerns on embodiment, and is a graph which shows the relationship between the average value for every drilling depth division of the correction attenuation amount for every drilling depth, and a shear wave velocity. . It is the schematic which shows the example of a display state of the result screen which concerns on embodiment. It is the schematic which shows the other example of a display state of the result screen which concerns on embodiment.

  Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings.

  First, with reference to FIGS. 1-2, the whole structure of the ground condition evaluation system 10 to which this invention was applied is demonstrated.

  As shown in FIG. 1, a ground condition evaluation system 10 according to the present embodiment includes a personal computer (hereinafter referred to as “PC”) 12 that plays a central role in the system 10 and a first accelerometer. 14, a second accelerometer 16, a dynamic strain amplifier 18, a data recorder 20, and a recording / output device 22.

  As shown in FIG. 2, the first accelerometer 14 is provided in a leader portion 32 of a ground drilling machine 30 that drills a ground to be evaluated (hereinafter referred to as “evaluation target ground”). The amplitude of vibration at the provided position is measured. Moreover, the 2nd accelerometer 16 is provided in the surface of the evaluation object ground, and measures the amplitude of the vibration in the said surface. In the ground condition evaluation system 10 according to the present embodiment, a plate (not shown) (in this embodiment, an iron plate with a thickness of 2 cm) is placed on the surface of the evaluation target ground, and the second is placed on the surface of the plate. However, depending on the hardness of the surface of the evaluation target ground, the second accelerometer 16 may be provided directly on the surface of the evaluation target ground. Further, in the ground condition evaluation system 10 according to the present embodiment, the first accelerometer 14 is provided 1.5 m above the ground surface in the leader portion 32 of the ground drilling machine 30, and the second accelerometer 16 is ground. Although provided in the position of the horizontal distance 4.5m from a hole position, it does not restrict to this.

  As shown in FIG. 1, an output terminal that outputs first acceleration information indicating the measurement result of the first accelerometer 14 and an output terminal that outputs second acceleration information indicating the measurement result of the second accelerometer 16. Are connected to the input terminal of the dynamic strain amplifier 18, and the output terminal of the dynamic strain amplifier 18 is connected to the input section of the data recorder 20. Therefore, the first acceleration information and the second acceleration information are received by the dynamic strain amplifier 18 and amplified to a predetermined level range, and then recorded by the data recorder 20.

  The position of the first accelerometer 14 is not limited to the reader unit 32, and may be any position of the ground drilling machine 30, but in order to improve the accuracy of the amount of attenuation described later, the ground to be evaluated The closer one is preferable. For example, the rod 34 may be provided. In this case, since the rod 34 rotates at the time of drilling, the measurement result by the first accelerometer 14 is wirelessly transmitted to the dynamic strain amplifier 18.

  On the other hand, the output unit of the data recorder 20 is connected to the input unit of the PC 12, while the output unit of the PC 12 is connected to the input unit of the recording / output device 22. Accordingly, the PC 12 can obtain the first acceleration information and the second acceleration information recorded in the data recorder 20 by reading out the various information based on the first acceleration information and the second acceleration information. Information can be recorded and output by the recording / output device 22. In the ground condition evaluation system 10 according to the present embodiment, the recording / output device 22 is a hard disk device for recording the various types of information, and a printer for outputting the various types of information. Needless to say, the device is not limited to this device as long as it can record or output various information.

  Next, with reference to FIG. 3, the configuration of the main part of the electrical system of the PC 12 having a particularly important role in this system will be described.

  As shown in the figure, the PC 12 according to the present embodiment includes a CPU (central processing unit) 12A that controls the operation of the entire PC 12, a RAM 12B that is used as a work area when the CPU 12A executes various processing programs, and the like. ROM 12C in which a control program, various parameters, and the like are stored in advance, a secondary storage unit (here, a hard disk device) 12D used as a storage unit for storing various information, and a keyboard used for inputting various information 12E, a display 12F used for displaying various types of information, and an input / output I / F (interface) 12G that controls transmission and reception of various signals between external devices and the like. They are electrically connected to each other by a bus BUS.

  Therefore, the CPU 12A accesses the RAM 12B, ROM 12C, and secondary storage unit 12D, obtains various input information via the keyboard 12E, displays various information on the display 12F, and external devices via the input / output I / F 12G. Various kinds of information can be exchanged between the two. The data recorder 20 and the recording / output device 22 described above are electrically connected to the input / output I / F 12G.

  On the other hand, FIG. 4 schematically shows the main storage contents of the secondary storage unit 12D provided in the PC 12. As shown in the figure, the secondary storage unit 12D is provided with a database area DB for storing various databases and a program area PG for storing programs for performing various processes. .

  The database area DB includes a measurement information database DB1 and a ground classification information database DB2.

  As schematically shown in FIG. 5 as an example, the measurement information database DB1 according to the present embodiment includes a first acceleration response for a predetermined period (1.8 seconds in the present embodiment), and Each information of the second acceleration response is configured to be stored for each predetermined depth of drilling by the ground drilling machine 30 (in this embodiment, every 1 m).

  The depth is obtained as the distance from the surface of the evaluation target ground to the drilling side tip of the rod 34 of the ground drilling machine 30.

  The first acceleration response is output from the first accelerometer 14 when the ground to be evaluated is drilled at the corresponding depth by the ground drilling machine 30, and the data / response is transmitted via the dynamic strain amplifier 18. It is information indicating the acceleration response recorded in the recorder 20, and the second acceleration response is obtained from the second accelerometer 16 when the ground to be evaluated is drilled at the corresponding depth by the ground drilling machine 30. This is information indicating the acceleration response that is output and recorded in the data recorder 20 via the dynamic strain amplifier 18.

  FIG. 7A shows an example of the first acceleration response, and FIG. 7B shows an example of the second acceleration response.

  By the way, in the ground condition evaluation system 10 according to the present embodiment, the average amplitude of the first acceleration response is calculated as the first amplitude based on the first acceleration response, and the second acceleration is calculated. Based on the response, the average amplitude of the second acceleration response is calculated as the second amplitude. The smaller the first amplitude, the higher the degree of softness of the evaluation target ground. It is evaluated that the more the amount of attenuation of the second amplitude with respect to the amplitude is, the more the evaluation target ground has more cracks.

  In the ground condition evaluation system 10 according to the present embodiment, the first amplitude is calculated by the following equation (1), and the second amplitude is calculated by the following equation (2). Here, in the expressions (1) and (2), u1 is the first amplitude, u2 is the second amplitude, and Td is the measurement period of the first acceleration response and the second acceleration response ( In this embodiment, 1.8 seconds), X1 (t) is the amplitude of the first acceleration response at time t, and X2 (t) is the amplitude of the second acceleration response at time t. To express.

また、本実施の形態に係る地盤状態評価システム１０では、地盤削孔機３０は作動しているが、削孔は行っていないときの第１の加速度計１４により得られた加速度応答（以下、「第１の暗加速度応答」という。）の平均的な振幅（以下、「第１の暗振幅」という。）を次の（３）により算出し、地盤削孔機３０は作動しているが、削孔は行っていないときの第２の加速度計１６により得られた加速度応答（以下、「第２の暗加速度応答」という。）の平均的な振幅（以下、「第２の暗振幅」という。）を次の（４）により算出する。ここで、（３）式および（４）式におけるａ１は上記第１の暗振幅を、ａ２は上記第２の暗振幅を、Ａ１（ｔ）は上記第１の暗加速度応答の時刻ｔにおける振幅を、Ａ２（ｔ）は上記第２の暗加速度応答の時刻ｔにおける振幅を、各々表す。

Further, in the ground condition evaluation system 10 according to the present embodiment, the ground drilling machine 30 is operating, but the acceleration response obtained by the first accelerometer 14 when the drilling is not performed (hereinafter, referred to as the “hole drilling machine 30”). An average amplitude of “first dark acceleration response” (hereinafter referred to as “first dark amplitude response”) is calculated by the following (3), and the ground drilling machine 30 is operating. The average amplitude (hereinafter, “second dark amplitude”) of the acceleration response (hereinafter referred to as “second dark acceleration response”) obtained by the second accelerometer 16 when no drilling is performed. Is calculated by the following (4). In the equations (3) and (4), a1 is the first dark amplitude, a2 is the second dark amplitude, and A1 (t) is the amplitude of the first dark acceleration response at time t. , A2 (t) represents the amplitude of the second dark acceleration response at time t.

また、本実施の形態に係る地盤状態評価システム１０では、第１の振幅ｕ１の補正値（以下、「第１の補正振幅」という。）および上記第２の振幅ｕ２の補正値（以下、「第２の補正振幅」という。）を次の（５）式および（６）式により算出する。ここで、（５）式および（６）式におけるｕ１’は上記第１の補正振幅を、ｕ２’は上記第２の補正振幅を、各々表す。

Further, in the ground condition evaluation system 10 according to the present embodiment, the correction value of the first amplitude u1 (hereinafter referred to as “first correction amplitude”) and the correction value of the second amplitude u2 (hereinafter, “ Is calculated by the following equations (5) and (6). In the equations (5) and (6), u1 ′ represents the first correction amplitude, and u2 ′ represents the second correction amplitude.

さらに、本実施の形態に係る地盤状態評価システム１０では、上記減衰量を次の（７）式により算出する。ここで、（７）式におけるｄは上記減衰量を表す。

Furthermore, in the ground condition evaluation system 10 according to the present embodiment, the attenuation amount is calculated by the following equation (7). Here, d in the equation (7) represents the attenuation amount.

そして、本実施の形態に係る地盤状態評価システム１０では、減衰量ｄを、地盤削孔機３０の削孔深度による影響を除去する、後述する削孔深度影響除去処理によって補正した補正減衰量ｄ’を算出して評価に用いる。

And in the ground condition evaluation system 10 according to the present embodiment, the attenuation d is corrected by a drilling depth effect removal process, which will be described later, which removes the influence due to the drilling depth of the ground drilling machine 30. 'Is used for evaluation.

  As schematically shown in FIG. 6 as an example, the ground classification information database DB2 according to the present embodiment includes the correction attenuation amount d for each predetermined first threshold value of the first correction amplitude u1 ′. Information indicating the state of the ground is stored according to a predetermined second threshold value of '.

  In the ground classification information database DB2 shown in FIG. 6, for example, when the first correction amplitude u1 ′ is less than the first threshold and the correction attenuation d ′ is less than the second threshold, the evaluation target ground is soft, And when the first correction amplitude u1 ′ is not less than the first threshold value and the correction attenuation d ′ is not less than the second threshold value, the evaluation target ground is hard, and This indicates that the ground has few cracks. The first threshold value and the second threshold value may be determined in advance according to the use of the ground condition evaluation system 10, required safety, or the like, or may be set by the user.

  In the ground condition evaluation system 10 according to the present embodiment, the first dark amplitude a1 and the second dark amplitude a2 are acquired in advance and stored in advance in a predetermined area of the secondary storage unit 12D.

  By the way, in the ground condition evaluation system 10 according to the present embodiment, the ground condition is evaluated for each of a plurality of predetermined drilling depth categories for the ground to be evaluated by the ground drilling machine 30.

  For this reason, in the ground condition evaluation system 10, information indicating the above-mentioned drilling depth division (hereinafter referred to as “drilling depth division information”) is stored in advance in a predetermined area of the secondary storage unit 12D.

  In the ground condition evaluation system 10 according to the present embodiment, the depth for each layer divided according to the magnitude of the shear wave velocity that has been previously determined for the evaluation target ground is shown as the drilling depth classification information. Although the information is applied, the present invention is not limited to this, for example, information indicating an equally spaced depth such as every 5 m, every 10 m, or every 20 m, or an arbitrary interval such as 10 m → 25 m → 30 m in order of increasing depth. Information indicating the depth of the image may be applied.

  Next, the operation of the ground condition evaluation system 10 according to the present embodiment will be described.

  First, the operation of the ground state evaluation system 10 when the information of the first acceleration response and the second acceleration response in the evaluation target ground is acquired and the measurement information database DB1 is constructed will be described.

  At this time, the operator performs drilling with respect to a predetermined drilling position in the evaluation target ground by the ground drilling machine 30.

  In the drilling process, the first acceleration information is output from the first accelerometer 14 in real time, and the second acceleration information is output from the second accelerometer 16 in real time.

  The acceleration information is amplified to a predetermined level range by the dynamic strain amplifier 18 and then recorded by the data recorder 20. At this time, the data recorder 20 stores each acceleration information in the predetermined period (in this embodiment) every time the drilling depth passes through the predetermined depth (1 m in this embodiment). , 1.8 seconds), the data is recorded in the data recorder 20 as the first acceleration response and the second acceleration response.

  Then, the PC 12 reads out the first acceleration response and the second acceleration response recorded in the data recorder 20 from the data recorder 20 and registers them in the measurement information database DB1.

  By the above process, the measurement information database DB1 shown in FIG. 5 is constructed as an example.

  Next, with reference to FIG. 8, the effect | action of the ground state evaluation system 10 which concerns on this Embodiment at the time of evaluating the state of an evaluation object ground using measurement information database DB1 constructed | assembled by the above procedure is demonstrated. . 8 shows the ground executed by the CPU 12A of the PC 12 when a user inputs an execution instruction for evaluating the ground state via an input device (not shown) such as a keyboard 12E provided in the PC 12. It is a flowchart which shows the flow of a process of a state evaluation process program, and the said program is beforehand memorize | stored in the program area | region PG of secondary storage part 12D. Here, a case will be described in which the measurement information database DB1 and the ground classification information database DB2 are constructed in advance in order to avoid complications.

  In step 100 in the figure, drilling depth classification information is read from the secondary storage unit 12D, and in the next step 102, all information (hereinafter referred to as “ground classification information”) is read from the ground classification information database DB2. In the next step 104, the first dark amplitude a1 and the second dark amplitude a2 are read from the secondary storage unit 12D.

  In the next step 106, all the first acceleration responses and second acceleration responses are read from the measurement information database DB1, and in the next step 108, all the read first acceleration responses and second acceleration responses are read out. Then, noise is removed from each acceleration response by applying a filtering process using a low pass filter. In the next step 110, all the first acceleration responses and the second acceleration response subjected to the filtering process are removed. The first amplitude u1 and the second amplitude u2 are calculated by the above-described equations (1) and (2).

  In the next step 112, the first amplitude u1 and the second amplitude u2 calculated by the process of step 110 and the first dark amplitude a1 and the first amplitude read by the process of step 104 are calculated for each corresponding drilling depth. The first correction amplitude u1 ′ and the second correction amplitude u2 ′ for each drilling depth are calculated by substituting 2 dark amplitudes a2 into the above-described equations (5) and (6).

  FIG. 9 shows a graph showing an example of the first correction amplitude u1 'for each drilling depth obtained by the above processing.

  In the next step 114, the attenuation d is calculated by substituting the first correction amplitude u1 ′ and the second correction amplitude u2 ′ for each drilling depth obtained by the above processing into the above-described equation (7). In the next step 116, the depth-of-drilling effect removal process for removing the influence of the depth of the ground drilling machine 30 on the calculated attenuation d is executed.

  When the evaluation target ground is assumed to be a semi-infinite elastic body, and the drilling hole is assumed to be a point vibration source, the attenuation d is expressed by the following equation (8). Here, h represents the internal damping constant of the evaluation target ground, f represents the frequency of vibration generated by drilling, V represents the propagation speed of vibration generated by drilling, and r represents the drilling depth.

一方、図１０には、以上の処理によって得られた削孔深度毎の減衰量ｄの一例を示すグラフが示されている。

On the other hand, FIG. 10 shows a graph showing an example of the attenuation d for each drilling depth obtained by the above processing.

  As shown by the equation (8), the attenuation d is theoretically proportional to the minus second power of the drilling depth r, but the approximate curve is about −1.85 at the attenuation d shown in FIG. 10. It is proportional to the power, and almost agrees with the theoretical value.

  In this step 116, in order to make it possible to compare the attenuation d of each drilling depth r without the influence of the drilling depth r, as shown in FIG. As shown in FIG. 10, the difference (hereinafter referred to as “correction attenuation amount”) d ′ between the attenuation amount d of each drilling depth and the power approximation curve is calculated.

  In the next step 118, the first correction amplitude u1 ′ and the correction obtained for each drilling depth by the above process for each drilling depth section indicated by the drilling depth section information read out by the process in step 100 above. The average value of each attenuation d ′ is calculated.

  FIG. 12 shows a graph showing an example of the average value of the first correction amplitude u1 ′ for each drilling depth section obtained by the processing of this step 118. FIG. The graph which shows an example of the average value of correction | amendment attenuation amount d 'for every drilling depth division obtained by the process is shown.

  In the next step 120, the average value of the first correction amplitude u1 ′ and the average value of the correction attenuation amount d ′ for each drilling depth section obtained by the above processing is the ground classification read out by the processing of step 102. It is specified which region of the ground classification (see also FIG. 6) indicated by the information belongs, and in the next step 122, an evaluation result in a predetermined format based on the specific result is shown. After configuring the information indicating the result screen, in the next step 124, the result screen is displayed on the display 12F based on the configured information, and then the ground condition evaluation processing program is terminated.

  FIG. 14 shows an example of the display state of the result screen displayed on the display 12F by the process of step 124 of the ground condition evaluation process program. As shown in the figure, in the ground condition evaluation processing program according to the present embodiment, the step 120 in the graph in which the first correction amplitude u1 ′ is the horizontal axis and the correction attenuation amount d ′ is the vertical axis is shown. As a result, a screen plotting information (in the example shown in the figure, “depth A”, “depth B”,..., “Depth F”) indicating the corresponding drilling depth category in the region specified by the processing Displayed as a screen. Therefore, the user of the ground condition evaluation system 10 can easily visually grasp the ground condition for each drilling depth category by referring to the result screen.

  As described above in detail, in the present embodiment, when the ground to be evaluated is drilled by the ground drilling machine, the amplitude of vibration measured by the ground drilling machine (first amplitude) ), The more the amount of vibration attenuation (second amplitude) on the surface of the ground is, the more cracks in the ground are evaluated, and information indicating the evaluation results is displayed. Thus, the ground condition can be evaluated with high accuracy and low cost.

  Further, in the present embodiment, the smaller the first amplitude is, the higher the softness of the ground is evaluated. Therefore, compared with the case where the evaluation is performed without using the first amplitude, The condition of the ground can be evaluated with high accuracy.

  In the present embodiment, the vibration component (here, dark amplitude) of the ground drilling machine itself is removed from the first amplitude and the second amplitude, and the vibration component of the ground drilling machine itself is The attenuation amount is derived and applied based on the removed first amplitude (here, the first correction amplitude u1 ′) and the second amplitude (here, the second correction amplitude u2 ′). Therefore, as a result of making the attenuation amount more accurate, the state of the ground can be evaluated with higher accuracy.

  In the present embodiment, the attenuation due to the depth of the hole is removed from the attenuation, and the attenuation (in this case, the corrected attenuation d ′) from which the influence due to the depth of the hole is removed. As a result, the attenuation amount can be made with higher accuracy, and as a result, the state of the ground can be evaluated with higher accuracy.

  In the present embodiment, since the evaluation is performed for each of a plurality of predetermined drilling depth sections for the ground by the ground drilling machine, the evaluation of the ground condition is performed for each drilling depth section. As a result, it is possible to improve convenience.

  Furthermore, in the present embodiment, since the evaluation is performed based on the relative magnitude relationship between the drilling depth sections, it is possible to perform relative evaluation on the same ground, thereby further improving convenience. Can do.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. Various modifications or improvements can be added to the above-described embodiment without departing from the gist of the present invention, and embodiments to which such modifications or improvements are added are also included in the technical scope of the present invention.

  The above embodiments do not limit the invention according to the claims (claims), and all the combinations of features described in the embodiments are essential for the solution means of the invention. Is not limited. The above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. Even if some constituent requirements are deleted from all the constituent requirements shown in the above-described embodiment, as long as an effect is obtained, a configuration from which these several constituent requirements are deleted can be extracted as an invention.

  For example, in the above embodiment, the case where a value obtained by dividing the second correction amplitude u2 ′ by the first correction amplitude u1 ′ is applied as the attenuation amount of the present invention, but the present invention is not limited to this. For example, a value obtained by subtracting the second correction amplitude u2 ′ from the first correction amplitude u1 ′, a value obtained by dividing the second amplitude u2 by the first amplitude u1, and a value obtained by subtracting the first amplitude u1 from the first amplitude u1. Other values may be applied as long as the values indicate the attenuation amount of the second amplitude u2 with respect to the first amplitude u1, such as a value obtained by subtracting the amplitude u2 of 2. In this case as well, the same effects as in the above embodiment can be obtained.

  Moreover, although the said embodiment demonstrated the case where the 1st correction | amendment amplitude u1 'was used and the case where the softness degree of the evaluation object ground was evaluated, this invention is not limited to this, For example, 1st The degree of softness of the evaluation target ground can be evaluated using the amplitude u1. In this case, although the evaluation accuracy for the evaluation target ground is slightly lower than that in the above embodiment, it is not necessary to derive the first dark amplitude a1, and as a result, the state of the ground can be evaluated more easily.

  Moreover, although the said embodiment demonstrated the case where the number of cracks of the evaluation object ground was evaluated using correction | amendment attenuation amount d ', this invention is not limited to this, For example, attenuation amount d It can also be set as the form which evaluates the number of cracks of the evaluation object ground using. In this case, it is not necessary to derive an approximate curve of the attenuation d, so that the ground state can be more easily evaluated.

  Moreover, although the said embodiment demonstrated the case where an evaluation object ground was evaluated for every drilling depth division, this invention is not limited to this, For example, it is 1st acceleration response to measurement information database DB1. And it can also be set as the form which evaluates an evaluation object ground for every drilling depth which registered the 2nd acceleration response. In this case, although the evaluation time is longer than that in the above embodiment, more detailed evaluation can be performed.

  In the above embodiment, the case where the evaluation target ground is evaluated using both the first corrected amplitude u1 ′ and the corrected attenuation amount d ′ has been described. However, the present invention is not limited to this. For example, the evaluation target ground may be evaluated using only the corrected attenuation amount d ′. In this case, although it becomes impossible to evaluate the degree of softness of the evaluation target ground, the state of the ground can be evaluated in a shorter time.

  Moreover, although the said embodiment demonstrated the case where the evaluation object ground was evaluated using one threshold value corresponding to each of correction | amendment attenuation amount d 'and 1st correction | amendment amplitude u1', this invention was demonstrated. Is not limited to this. For the corrected attenuation d ′, it is evaluated that the larger the corrected attenuation d ′ is, the more cracks are in the evaluation target ground, and the first corrected amplitude u1 ′ is For example, if the evaluation amplitude u1 ′ of 1 is smaller and the degree of softness of the evaluation target ground is higher, for example, both the correction attenuation amount d ′ and the first correction amplitude u1 ′ use a plurality of threshold values. The evaluation target ground may be evaluated.

  Further, in the above embodiment, the first acceleration response and the second acceleration response are temporarily stored in the storage means (in the above embodiment, the data recorder 20), and these acceleration responses are read out to relate to the present invention. Although the case where the attenuation amount is derived and applied has been described, the present invention is not limited to this. For example, the output from the first accelerometer 14 when the ground is drilled by the ground drilling machine 30. The peak values of the first acceleration information and the second acceleration information output from the second accelerometer 16 are detected in real time by a sample and hold circuit or the like, and the peak values of the first acceleration information with respect to the peak values of the first acceleration information are detected. It is also possible to adopt a form in which the attenuation amount of the peak value of the acceleration information of 2 is derived and applied. In this case, it is not necessary to provide the storage means, and real-time ground evaluation can be realized.

  In addition, the configuration of the ground condition evaluation system 10 described in the above embodiment (see FIGS. 1 to 4) is merely an example, and unnecessary portions may be deleted or newly added without departing from the gist of the present invention. Needless to say, you can add new parts.

  The data structure of each database shown in the above embodiment (see FIGS. 5 and 6) is also an example, and unnecessary information can be deleted or new information can be deleted without departing from the gist of the present invention. Needless to say, you can add.

  The processing flow of the ground condition evaluation processing program shown in the above embodiment (see FIG. 8) is also an example, and unnecessary steps can be deleted or new within the scope of the gist of the present invention. It goes without saying that steps can be added and the processing order can be changed.

  The configuration of the result screen shown in the above embodiment (see FIG. 14) is also an example, and it goes without saying that it can be changed without departing from the gist of the present invention.

  For example, as shown in FIG. 15, as an example, the ground classification is specified in the same manner as in the above-described embodiment for a plurality of drilling locations in the evaluation target ground, and the identification results are visually collected for the plurality of drilling locations. It is good also as a form to display. In this case, since the state of the ground can be confirmed on one screen for a plurality of drilling locations, it is more convenient.

  Furthermore, various arithmetic expressions (see the expressions (1) to (8)) shown in the above embodiment are also examples, and it goes without saying that they can be changed without departing from the gist of the present invention.

10 ground condition evaluation system 12 personal computer 12A CPU (evaluation means, display means, removal means, second removal means)
12B RAM
12C ROM
12D Secondary storage unit 12E Keyboard 12F Display 12G Input / output interface 14 First accelerometer (first measurement means)
16 Second accelerometer (second measuring means)
18 Dynamic strain amplifier (receiver)
20 Data Recorder 22 Recording / Output Device 30 Ground Drilling Machine 32 Leader Section 34 Rod

Claims (8)

A first measuring means provided in a ground drilling machine for drilling the ground to be evaluated, and measuring a vibration amplitude at the provided position and outputting a first signal;
A second measuring means for measuring the amplitude of vibration on the surface of the ground and outputting a second signal;
Receiving means for receiving the first signal output by the first measuring means and the second signal output by the second measuring means when the ground is drilled by the ground drilling machine. When,
Evaluation means for evaluating that the greater the amount of attenuation of the second amplitude obtained by the second signal with respect to the first amplitude obtained by the first signal received by the receiving means, the more cracks in the ground. ,
Display means for displaying information indicating an evaluation result by the evaluation means;
Ground condition evaluation device with The ground state evaluation device according to claim 1, wherein the evaluation means evaluates that the softness of the ground is higher as the first amplitude is smaller. A removal means for removing a vibration component of the ground drilling machine itself from the first amplitude and the second amplitude;
The evaluation unit derives and applies the attenuation amount based on the first amplitude and the second amplitude from which the vibration component of the ground drilling machine itself has been removed by the removing unit. The ground condition evaluation device described. A second removing means for removing the influence of the depth of the drilling hole from the attenuation amount;
The ground state evaluation apparatus according to any one of claims 1 to 3, wherein the evaluation unit applies the attenuation amount in which the influence of the depth of the drilling hole is removed by the second removal unit. The ground condition evaluation apparatus according to any one of claims 1 to 4, wherein the evaluation unit performs the evaluation for each of a plurality of predetermined drilling depth categories for the ground by the ground drilling machine. The ground condition evaluation apparatus according to claim 5, wherein the evaluation means performs the evaluation based on a relative magnitude relationship between the drilling depth sections. Computer
The greater the amount of vibration amplitude attenuation at the surface of the ground relative to the amplitude of vibration of the ground drilling machine when the ground is drilled by a ground drilling machine that drills the ground to be evaluated An evaluation means for evaluating that there are many cracks in the ground,
Display means for displaying information indicating an evaluation result by the evaluation means;
Program to function as.   The program for functioning a computer as an evaluation means and a display means in the ground condition evaluation apparatus of any one of Claims 1-6.

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