JP5542593B2 - Ground cutting condition monitoring method and monitoring device in high-pressure jet agitation method - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a ground cutting state monitoring method and a monitoring apparatus implemented by a high-pressure jet agitation method, and high-pressure jetting is performed while creating a ground improvement body by stirring and mixing solidified material and raw soil to be high-pressure jetted. By grasping the cutting state of the original ground by the solidified material in real time, the diameter of the ground improvement body being created can be determined.

  In general, the high-pressure jet agitation method is a method in which a solidified material is injected at a high pressure from an injection nozzle at its tip through an injection pipe inserted into the ground, and the ground is cut and collapsed by its powerful energy, and the solidified material and the soil This is a method for forcibly stirring and mixing to create a cylindrical improvement body, and is known as a ground improvement method that can be used for multiple purposes from temporary installation to main construction.

  However, since the stirring and mixing of the raw soil and the solidified material is performed in the ground and cannot be visually observed, it is necessary to check the construction status. Conventionally, this type of confirmation has been performed by methods such as check boring performed after construction and a part of the head of the ground improvement body being exposed.

  Further, for example, in Patent Document 1, the specific resistance of the surrounding ground improvement pillar and soil is measured by an electrode group in a sonde suspended from the tip of the injection tube, and the ground that is being formed based on the measured value A confirmation method for estimating the finished state of the improved body is described.

  Patent Document 2 discloses a high-pressure jet agitation method in which a slurry containing a cement-based solidified material mainly composed of oxidized calcium is injected and stirred into the ground to form a cylindrical ground improvement body. The method of estimating the diameter of a ground improvement body from the content rate of a calcium oxide is described using the relationship that the diameter of the ground improvement body created is so small that a rate is large.

Japanese Patent Application Laid-Open No. 07-18660 JP 2007-182695 A Japanese Patent Laid-Open No. 08-41860 JP 2009-102892 A Japanese Patent Laid-Open No. 7-180136 JP 2002-206233 A JP 2009-102897 A

  However, check boring and the method of confirming the diameter of the ground improvement body by partially exposing the head of the ground improvement body are methods that are performed after the ground improvement body is created. However, it was not possible to respond immediately, and it was necessary to install and install the device again, which was extremely inefficient.

  The present invention was made to solve the above problems, and provides a ground cutting state monitoring method and monitoring device in a high-pressure jet agitation method capable of confirming in real time the diameter of a ground improvement body being created. It is the purpose.

Cutting state monitoring method of the ground in claim 1 high-pressure injection agitation method of description is therefore from the injection nozzle of the injection tube inserted in the ground to a solidifying material is high-pressure injection, which is inserted into the ground around the injection tube In the ground cutting state monitoring method for confirming the cutting state of the ground by monitoring the vibration generated by the built-in pipe with a detector, each of the vertical holes is drilled at a plurality of points at different distances from the injection pipe. After inserting the erection pipes into the vertical holes and filling the surroundings with a sealing material to fix the erection pipes in the vertical holes, and vertically suspending the detectors in the erection pipes, The solidification material is jetted at a high pressure from the jet nozzle of the injection pipe .

  The present invention creates a ground improvement body composed of a solidified material and high-pressure sprayed from a spray nozzle of an injection pipe inserted into the ground, and simultaneously cuts the ground using a solidified material sprayed from a spray nozzle at high pressure. The status can be checked in real time.

  According to the present invention, the vibration of the built-in pipe generated when the solidified material injected from the injection nozzle of the injection pipe hits the built-in pipe inserted into the ground surrounding the injection pipe is detected in real time by the detector. By monitoring and evaluating this as cutting energy, it is possible to easily determine the diameter of the ground improvement body being created simultaneously with the creation of the ground improvement body in real time.

  Insert multiple built-in pipes at multiple points around the injection pipe, changing the distance from the injection nozzle at the tip of the injection pipe (the reach of the solidification material) as appropriate, and install detectors in each built-in pipe. Can do.

  The distance from the injection nozzle to each built-in pipe can be set according to the properties of the original ground such as the N value and viscosity of the original ground. A gas pipe or the like is suitable as long as it has a diameter that can be installed.

The ground cutting state monitoring method in the high-pressure jet stirring method according to claim 2. The ground cutting state monitoring method in the high-pressure jet agitation method according to claim 1 , wherein a sound collecting microphone is installed as a detector in an air packer that is expanded by sealing air and fixed in a built-in pipe. The cutting state of the ground is confirmed by monitoring the sound that hits the built-in pipe of the solidified material that has been jetted at high pressure by the sound microphone .

In addition, the sound collector is equipped with a packer, so that the sound collecting microphone can be easily placed at any position in the built-in pipe by inflating the packer with air from the ground via an air hose. Can be fixed.

  Further, since the sound collecting microphone is housed in a sealed state in the packer, the sound collecting property is good, and the sound that hits the built-in pipe of the solidified material can be clearly monitored. Further, waterproof performance can be imparted to the sound collecting microphone.

  The ground cutting state monitoring method in the high-pressure jet agitation method according to claim 4 is characterized in that in the ground cutting state monitoring method according to any one of claims 1 to 3, the built-in pipe is filled with water. To do.

  According to the present invention, since the weight of the erected pipe is increased by the water in the erected pipe, the erected pipe can be easily installed in the vertical hole.

  In addition, by filling the entire built-in pipe with water except inside the packer that houses the sound collecting microphone, the sound collection range is limited only to the vicinity of the sound collecting microphone. And sound can be monitored more clearly, and noise transmitted from the ground via the built-in pipe can be blocked.

4. Cutting state monitoring device of the ground in the high-pressure injection stirring method according is inserted from the injection nozzle of the injection tube inserted in the ground I by the solidifying material is high-pressure injection, in the ground around the injection tube In the ground cutting state monitoring device for confirming the cutting state of the ground by monitoring the vibration generated by the built-up pipe by means of a detector , each vertical pipe formed at a plurality of points at different distances from the injection pipe. each is inserted into the hole, and a plurality of construction inclusive tube secured within each longitudinal hole by filling a sealing material around the respective provided perpendicularly to each Kenkomi tube, is high-pressure injection from the injection nozzle and it is characterized in that it comprises a plurality of detectors for monitoring the vibration of Kenkomi tubes that emit by that solidified material.

  The detector can be a sound collecting microphone or vibration meter that monitors the sound or vibration that hits the built-in pipe of solidified material injected with high pressure, and the sound collecting microphone or vibration meter is placed in a protective cover or rubber packer. It is desirable to be stored.

  In particular, the latter detector can be easily fixed at an arbitrary position in the built-in pipe by enclosing and expanding air in the packer. Further, since the sound collecting microphone and the vibrometer are stored in the packer in a sealed state, there is an advantage that the sound and vibration that hit the built-in pipe of the solidified material can be clearly monitored.

The ground cutting state monitoring device in the high pressure jet stirring method according to claim 5 is the ground cutting state monitoring device in the high pressure jet stirring method according to claim 4, wherein the detector is stepped up in conjunction with the step-up of the spray nozzle. A lifting device, a management device for centrally managing the information monitored by the detector, and a recording device for recording the monitored information, wherein the detector collects a sound hitting the built-in pipe And is housed in an air packer that is expanded by being sealed with air and fixed in the built-in pipe .

  The management device can centrally manage vibration and sound data monitored by the detector, convert them into impact strength, and further digitize them.

  In addition, a data logger, a pen recorder, or the like can be used as the recording device, and in any case, monitored vibration and sound data can be recorded over time on a recording paper such as a chart paper.

  The present invention relates to the vibration of the built-in pipe generated when the solidified material injected at high pressure from the injection nozzle of the injection pipe inserted into the ground hits the built-in pipe inserted into the ground around the injection pipe, or the like By monitoring the sound with a detector installed in the built-in pipe, the cutting state of the original ground can be grasped and evaluated in real time.

  In addition, this makes it possible to easily grasp the diameter of the ground improvement body being built at the same time as creating the ground improvement body. There is no need to re-work such as partially exposing and checking the diameter of the ground improvement body.

It is a schematic diagram showing the present invention. It is a longitudinal cross-sectional view which shows the built-in pipe installed in the ground. The sound collector installed in the built-in pipe is shown. (A) is a cross-sectional view showing the sound collector composed of the packer and the sound collecting microphone housed in the packer. (B) is in the protective cover and the protective cover. It is sectional drawing which shows the sound collector which consists of the accommodated sound collection microphone. It is a schematic diagram which shows the principal part of a monitoring apparatus. It is a flowchart which shows the implementation method of monitoring. It is a graph which shows the relationship between the injection time of the solidification material in the ground, and the volume level of the sound which a solidification material hits a built-in pipe. It is a graph which shows the evaluation point of the graph alignment in FIG. 6, and the excavated ground improvement body completed form (relationship between an erected pipe position and a pile formation end). It is a graph which shows the fluctuation width of the volume level for every measuring point in each depth. It is a graph which shows the relationship between the fluctuation width of a volume level, and the ground improvement body completed shape dug.

  1 to 4 show an embodiment of the present invention. In the figure, reference numeral 1 is an injection pipe inserted into the ground, and 2 is an injection pipe 1 suspended through a swivel 3 so as to be perpendicular to the ground surface. It is a crane to be built.

  An injection nozzle 1a for injecting the solidified material at a high pressure is provided at the tip of the injection tube 1 and a water discharge port (not shown) for discharging the drilling water is provided below. Both the solidification material and the drilling water are supplied from the ground via the injection pipe 1.

  Reference numeral 4 denotes a construction machine for inserting the injection tube 1 into the ground and creating a cylindrical ground improvement body i made of raw soil and solidified material in the ground via the injection tube 1. .

  In such a configuration, the water can be inserted into the ground while rotating the injection pipe 1 by the construction machine 4 while discharging the drill water from the water outlet at the tip of the injection pipe 1.

  In addition, the solidification material is injected into the side from the injection nozzle 1a at the tip of the injection tube 1 at a high pressure, and the solid material is ground and the raw soil by rotating the injection tube 1 while cutting and collapsing the raw ground by the strong energy. The ground improvement body a can be created by forcibly stirring and mixing. Furthermore, the ground improvement body i can be formed in a cylindrical shape by gradually pulling up the injection tube 1.

  Reference numeral 5 denotes a built-in pipe inserted into the planned diameter of the ground improvement body a to be created, 6 a sound collector suspended from the built-in pipe 5 via a suspension cable 7, and 8 a built-in pipe. 5 is a hoisting device for lowering and raising the sound collector 6 in conjunction with the lowering and raising of the injection tube 1 via the suspension cable 7.

  The erection pipe 5 is inserted into the ground at a plurality of points around the injection pipe 1 to the planned depth of the ground improvement body i prior to the creation of the ground improvement body i. The insertion point of the built-in pipe 5 and the distance from the injection pipe 1 (the reach of the solidified material) are appropriately set according to the ground properties such as the N value and viscosity of the original ground.

  Further, the built-in pipe 5 is inserted into a vertical hole 9 drilled in advance by boring or the like, and a sealing material 10 is injected into a gap between the built-in pipe 5 and the vertical hole 9. A low-strength solidifying material that solidifies in the vertical hole 9 is used for the sealing material 10, and the built-in pipe 5 is fixed in the vertical hole 9 when the sealing material 10 is solidified in the vertical hole 9.

  In this case, the built-in pipe 5 has a closed end, and a gas pipe having a diameter (about 50 to 100 mm) that can accommodate the sound collector 6 is used. The seal material 10 is made of low-strength cement bentonite or the like.

  The sound collector 6 includes a rubber packer 6a and a sound collection microphone 6b housed in the rubber packer 6a. The rubber packer 6a expands and contracts in the built-in pipe 5 by the air sealed from the ground via the air hose 11, and the rubber packer 6a expands and comes into close contact with the inner wall of the built-in pipe 5, whereby the sound collector 6 Can be fixed at any position in the built-in pipe 5.

  The sound collecting microphone 6b can monitor in real time the sound that the solidified material injected from the injection nozzle 1a hits the built-in pipe 5, and the hoisting device 8 moves up and down the built-in pipe 5 together with the rubber packer 6a. Can descend.

  The rubber packer 6a is expanded to make the rubber packer 6a hollow, and the built-in pipe 5 is filled with water to limit the sound collection range only to the vicinity of the sound collection microphone 6b. The sound hitting the enclosing pipe 5 can be monitored more clearly. Moreover, the noise transmitted from the ground via the built-in pipe 5 can be blocked, and waterproof performance can be imparted to the sound collecting microphone 6b.

  Reference numeral 12 denotes a sound (hereinafter referred to as “sound data”) hitting the solidified material built-in pipe 5 monitored by the sound collector 6 suspended in the built-in pipe 5 at each point A, B, C, D. Reference numeral 13 denotes a management apparatus that performs centralized management, and reference numeral 13 denotes a recording apparatus that converts sound data managed by the management apparatus 12 into impact intensity, and further digitizes and records and stores the data. Note that the sound data monitored by each sound collector 6 is transmitted to the management apparatus 12 via a telegraph cable (not shown).

  Next, the construction method will be described based on the flowcharts shown in FIGS.

(1) First, the vertical holes 9 are drilled at a plurality of points A, B, C, and D in the planned range of the ground improvement body i to be created. Then, the erection pipes 5 are installed in the respective vertical holes 9, and the sealing material 10 is filled between the erection pipes 5 and the vertical holes 9.

  Boring can be used for drilling the vertical holes 9. Moreover, the built-in pipe 5 built in each vertical hole 9 can be fixed when the sealing material 10 solidifies. Furthermore, the insertion points A, B, C, and D of the built-in pipe 5 can be appropriately determined according to the ground properties of the original ground such as the N value and viscosity of the original ground.

  In addition, when the erected pipe 5 is installed in the vertical hole 9, water is poured into the erected pipe 5 in advance, and the weight of the entire pipe is increased to increase the buoyancy received by the erected pipe 5. The embedded tube 5 can be smoothly built into the vertical hole 9.

(2) Next, the construction machine 4 is installed at the center of the construction position of the ground improvement body i, and the injection pipe 1 is suspended from the construction machine 4 by the crane 2 and installed. And drilling water is discharged from the front-end | tip of the injection pipe 1, and it inserts to the planned depth in the ground, rotating the injection pipe 1 with the construction machine 4. FIG.

(3) Next, the hoisting device 8 is installed at each point A, B, C, D, and the sound collector 6 is suspended through the suspension cable 7 in the built-in pipe 5 into which water has been injected from each hoisting device 8. To do.

  The sound collector 6 is suspended from the same depth (stage) as the injection nozzle 1 a at the tip of the injection tube 1. Then, the packer 6a is expanded and fixed by enclosing air into the packer 6a of the sound collector 6 through the air hose 11 from the ground.

(4) Next, the solidifying material is injected at high pressure from the injection nozzle 1a through the injection pipe 1, and the injection pipe 1 is rotated at a constant speed by the construction machine 4 while cutting and collapsing the original ground by the strong energy. The ground soil and solidified material are forcibly stirred and mixed to create the ground improvement body a.

  During this time, if the solidified material injected at high pressure from the injection nozzle 1a at the tip of the injection tube 1 reaches each point A, B, C, D, the ground at each point is cut and collapsed, and is inserted into each point. The solidified material hits the built-up pipe 5 and a sound hitting the solidified material is generated on the built-in pipe 5 at each point.

  The sound at each point is monitored by the sound collecting microphone 6b of the sound collector 6 suspended in each built-in pipe 5, and the sound data monitored is managed on the ground via a telegraph cable (not shown). 12 is transmitted.

  Then, it is centrally managed by the management device 12, converted into impact strength, digitized, and recorded in the recording device 13. The recorded sound data is output as a chart to a pen recorder. The data measured here is the elapsed time, depth, step signal, and sound data at each point.

(5) Thus, when the creation of the ground improvement body i in the first stage is completed, the construction machine 4 is operated to step up the injection pipe 1 step by step to the second, third stage,. Then, by performing the step (4) in each stage, the ground improvement body i can be formed in a columnar shape.

  In the meantime, at each stage, the sound hitting the solidified material against the built-in pipe 5 at each point A, B, C, D can be monitored by the sound collecting microphone 6b, and digitized and recorded by the recording device 13. be able to.

(6) Next, when the ground improvement from the first stage to several stages is completed, the air in the air packer 6a is removed and the fixing of the sound collector 6 is released.

  Then, the hoisting device 8 is operated to raise the sound collector 6 to the next stage, and the air packer 6a is expanded again at that position to fix the sound collector 6 in the injection tube 5 again. The sound collector 6 is raised by receiving the step-up signal from the injection tube 1 and operating the hoisting device 8 in conjunction therewith.

(7) Then, as explained in (5), the injection tube 1 is stepped up stepwise while rotating the injection tube 1 while injecting the solidified material from the injection nozzle 1a at the tip of the injection tube 1 at a high pressure. By doing so, the ground improvement body i can be formed in a cylindrical shape.

In the meantime, in each stage, the sound hitting the solidified material against the built-in pipes 5 at the respective points A, B, C, D can be monitored by the sound collecting microphone 6b and digitized and recorded in the recording device 13. be able to.
As described above, the columnar ground improvement body i can be created by continuously performing the steps (4) to (7) from the first planned depth to the ground surface. Moreover, the pile diameter in each stage of the ground improvement body i of each point A, B, C, D can be determined.

  Although depending on the size (length) of the packer 6a, when the length of the packer 6a is about 200 mm, the packer 6a is inflated and the sound collector 6 is fixed in the built-in pipe 5 with a high pressure. It is desirable to step up the injection tube 1 by setting one step of the injection nozzle 1a to about 25 mm (see FIG. 3). The sound collector 6 is preferably raised about 100 mm to 200 mm every four steps up of the injection tube 1.

  By continuously performing the above steps, each point A of the ground improvement body I being simultaneously created while creating the ground improvement body i consisting of the solidified material and the raw soil sprayed at high pressure from the injection nozzle 1a, The sound generated by the built-in pipe 5 at each stage of B, C, and D can be monitored and recorded in real time. And the diameter of the ground improvement body i currently being constructed from the result can be easily determined in real time at the construction stage.

  FIG. 3B shows a modification of the sound collector. The sound collector 6 shown in the figure is easy to manufacture and can be used easily, and is housed in a cylindrical protective cover 6c and a protective cover 6c. And a sound collecting microphone 6b.

  The protective cover 6c merely protects the sound collecting microphone 6b, does not have an expansion function like a rubber packer, is formed from a cylindrical body such as a steel pipe or a hard resin pipe, and its upper and lower ends are sealed.

  The sound collector 6 configured in this manner is suspended in the built-in pipe 5 via the suspension cable 7 and is lowered and raised in conjunction with the lowering and raising of the injection pipe 1. Other configurations and usage methods are the same as those of the sound collector shown in FIG.

  Next, the method for determining the pile diameter by the ground cutting state monitoring method of the present invention will be specifically described by taking as an example the case of creating ground improvement bodies A, B, and C.

  FIG. 6 is a graph showing the relationship between the solidifying material injection time and the sound volume level at which the solidifying material hits the built-in pipe 5 during the improvement. Moreover, FIG. 7 is a graph which shows the evaluation point of the graph linearity in FIG. 6 and the finished shape of the excavated improved body (the relationship between the erected pipe position and the building end).

  Further, FIG. 8 is a graph showing the fluctuation level (= maximum value−minimum value) of the sound volume level for each measuring point at each depth, particularly during the construction of the improved body i. And FIG. 9 is a graph which shows the relationship between the amplitude of the volume level and the excavated ground improvement form.

(1) First, the time when the solidified material (jet flow) hits the built-in pipe 5 is confirmed from the graph of FIG. When the solidified material (injection flow) reaches the built-in pipe 5, a mountain-shaped graph shape can be confirmed at regular intervals, and the injection energy is proportional to the size of the mountain.

  In FIG. 6, a mountain-shaped graph alignment can be confirmed at regular intervals of about 6 seconds at four points A, B, C, and D (see FIG. 4), and a large mountain shape is clearly shown particularly at point A. On the other hand, a mountain shape can be confirmed at point D, but the size of the mountain is smaller than the others. Further, it can be seen from the graph of FIG. 7 that there is a correlation that the higher the evaluation of the graph linearity, the better the completed shape.

(2) Next, the amplitude of the volume level is calculated for each step and evaluated by the value of the amplitude.
The difference between the maximum value (the peak of the mountain) and the minimum value in FIG. FIG. 8 summarizes the amplitude of each measurement point at each depth.

  The greater the deflection width, the greater the injection energy of the solidified material that has reached the built-in pipe 5. That is, it is considered that reliable cutting is performed. Figure 9 summarizes the relationship between the excavated improved bodies I, B, and C. Thus, there is a correlation between the runout width and the finished product.

  When the fluctuation level of the volume level exceeds 200, the finished shape of the improved body reaches the outside of the built-in pipe 5.

  The present invention is capable of grasping in real time the cutting state of the original ground by the solidified material sprayed at high pressure at the same time while creating a ground improvement body composed of the solidified material injected from the injection nozzle at the tip of the injection pipe and the raw soil. Thus, the diameter of the ground improvement body being created can be determined.

DESCRIPTION OF SYMBOLS 1 Injection pipe 1a Injection nozzle 2 Crane 3 Swivel 4 Construction machine 5 Built-in pipe 6 Sound collector (detector)
6a Rubber packer 6b Sound collecting microphone 7 Hanging cable 8 Winding device 9 Vertical hole 10 Sealing material 11 Air hose 12 Management device 13 Recording device

Claims (5)

Thus from the injection nozzle of the injection tube inserted in the ground to a solidifying material is high-pressure injection, cutting state of the ground by monitoring the vibration detectors emitted by said injection tube surrounding soil during construction included tube inserted In the ground cutting state monitoring method to check the vertical holes, vertical holes are drilled at a plurality of points at different distances from the injection pipe , and a built-in pipe is inserted into each vertical hole, and a sealant is filled around it. By fixing the built-in pipes in the vertical holes, and suspending the detectors in the built-in pipes, the solidification material is jetted from the injection nozzle of the injection pipe at a high pressure. Ground cutting condition monitoring method in high-pressure jet agitation method. The ground cutting state monitoring method in the high-pressure jet agitation method according to claim 1 , wherein a sound collecting microphone is installed as a detector in an air packer that is expanded by sealing air and fixed in a built-in pipe. A ground cutting state monitoring method in a high pressure jet agitation method, wherein the ground cutting state is confirmed by monitoring a sound hitting a built-in pipe of a solidified material jetted at high pressure by a sound microphone .   The ground cutting state monitoring method in the high pressure jet agitation method according to claim 2, wherein water is filled in a built-in pipe excluding the inside of the air packer. I'm from the injection nozzle of the injection tube inserted in the ground to a solidifying material is high-pressure injection, the vibration detection device of the ground by monitoring the emitted from the injection pipe around the ground in the construction inclusive tube inserted In the ground cutting state monitoring device for confirming the cutting state , each is inserted into each of the vertical holes formed at a plurality of points at different distances from the injection tube , and the periphery thereof is filled with a sealing material. a plurality of construction inclusive tube secured within each vertical bore, each provided perpendicularly to each Kenkomi tube, a plurality of detectors for monitoring the vibration of Kenkomi tube emitting the solidifying material is high-pressure injection from the injection nozzle A ground cutting state monitoring device in a high-pressure jet stirring method characterized by comprising: In the cutting state monitoring device of the ground in the high-pressure injection stirring method according to claim 4, wherein the raised device that makes the step-up the detector in conjunction with step-up of the injection nozzle, to centralize information monitored by said detector management Device and a recording device for recording monitored information, and the detector is a sound collecting microphone for collecting sound hitting the built-in pipe, and is inflated by enclosing air and fixed in the built-in pipe The ground cutting state monitoring device in the high-pressure jet agitation method, wherein the ground cutting state monitoring device is housed in an air packer .

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