JP2011226250A - Quality control method for soil improvement body, measuring method and measuring rod - Google Patents

Abstract

PROBLEM TO BE SOLVED: To check the shape of a soil improvement body represented by a diameter thereof in realtime during creation of the soil improvement body and control the quality of the soil improvement body.SOLUTION: The quality control method for a soil improvement body 5 which is created by injecting a hardening solution 6 at high pressure from an injecting rod 12 penetrating into the soil comprises: installing optical fiber measuring devices 21, 22 and 23 measuring at least one of temperature and distortion in advance in the soil in which the soil improvement body 5 is created; and continuously measuring at least one of temperature and distortion of the soil in which the soil improvement body 5 is created by the optical fiber measuring devices 21, 22 and 23 during creation of the soil improvement body 5, and tracking a history of the measurement result to check the shape of the soil improvement body 5 represented by a diameter thereof in realtime.

Description

  The present invention relates to a quality control method for a ground improvement body created by a high-pressure jet stirring method, a method for measuring the shape of a ground improvement body created by a high-pressure jet stirring method or a chemical injection method, and a ground improvement body created by a chemical injection method The present invention relates to a measuring rod used in a method for measuring the shape of the above.

  Conventionally, the improved shape represented by the diameter and radius of the ground improvement body created by the high-pressure jet agitation method is the method of excavating the ground on the ground surface after solidifying the improved body and directly measuring it with a scale, etc. It was confirmed by the method of performing check boring.

  However, the direct measurement method using the scale cannot be performed when the ground improvement body is built deep in the ground. Also, the method of performing check boring is that when a drilling hole is provided at the boundary between the improved body and the ground, there is a difference in strength between the improved body and the ground. Can not.

  For such a problem, for example, Patent Document 1 discloses a method of measuring the diameter of a cylindrical ground improvement body formed in the ground, from the ground surface separated by a predetermined distance from the center point of the ground improvement body, A method is described in which drilling is performed while tilting in a direction penetrating through the center point of the ground improvement body, and the diameter of the ground improvement body is accurately confirmed by a change in excavation resistance at that time.

JP 2003-213663 A

  However, since the method described in Patent Document 1 is performed after the ground improvement body is created, depending on the strength of the improvement body after solidification and the soil soil quality, the excavation hole penetrating the improvement body is improved. It may be difficult to drill accurately to pass through the center point of the.

  The subject of this invention is confirming the shape represented by the diameter of a ground improvement body in real time during creation of a ground improvement body, and managing the quality of a ground improvement body.

  In order to solve the above problems, the invention according to claim 1 is a quality control method of a ground improvement body formed by high-pressure injection of a hardening material liquid from an injection rod penetrating into the ground, the ground improvement body An optical fiber measuring device that measures at least one of temperature and strain is installed in advance on the ground on which the ground improvement is to be created, and the temperature or strain of the ground on which the ground improvement body is created during the creation of the ground improvement body And a management step of confirming the shape typified by the diameter of the ground improvement body in real time by continuously measuring at least one of the optical fiber measuring instrument and tracking the history of the measurement results. And

  Invention of Claim 2 is the quality control method of the ground improvement body of Claim 1, Comprising: The temperature of the ground where the said ground improvement body is created by the said optical fiber measuring device before the said management process. It is characterized by comprising the step of measuring.

  Invention of Claim 3 is the quality control method of the ground improvement body of Claim 1 or 2, Comprising: In the said management process, the said ground improvement body is created during creation of the said ground improvement body. Both the temperature and strain of the ground are continuously measured by the optical fiber measuring instrument.

  Invention of Claim 4 is a measuring method of the shape represented by the diameter of the ground improvement body which carries out high pressure injection of the hardening | curing material liquid from the injection rod inserted in the ground, and is formed, Comprising: The said ground improvement body is created. An optical fiber measuring instrument for measuring at least one of temperature and strain is inserted into the ground, and at least one of the temperature or strain of the ground on which the ground improvement body is created is created by the optical fiber measuring instrument during the creation of the ground improvement body. By continuously measuring, the shape typified by the diameter of the ground improvement body is measured.

  The invention according to claim 5 is a method of measuring a shape typified by a diameter of a ground improvement body formed by injecting a chemical solution into the ground, and an optical fiber for measuring temperature on the ground for forming the ground improvement body By inserting a measuring device and continuously measuring the temperature of the ground on which the ground improvement body is created during the creation of the ground improvement body, the diameter of the ground improvement body is represented by the optical fiber measuring device. The shape is measured.

  The invention described in claim 6 is a measuring rod that is inserted into the ground and measures the temperature of the ground, and is provided with an optical fiber measuring device that measures the temperature of the surrounding ground.

  According to the present invention, the shape represented by the diameter of the ground improvement body can be confirmed in real time by continuously measuring the temperature and strain of the ground with an optical fiber measuring instrument during the creation of the ground improvement body. It is possible to control the quality so that the ground improvement body is formed in a shape represented by an appropriate diameter.

It is a figure which shows the construction condition of the quality control method of the ground improvement body which concerns on this embodiment. It is arrow sectional drawing of the surface along the II-II line | wire shown by FIG. It is explanatory drawing explaining the effect of this embodiment. It is a figure which points out the problem of the temperature measurement by the thermocouple of the ground improvement body by chemical | medical solution injection | pouring. It is a figure which shows the temperature measurement by the optical fiber measuring device of the ground improvement body by chemical | medical solution injection | pouring. It is an enlarged view which shows the specific structure of the optical fiber measuring device of FIG. It is a figure which shows Embodiment 2 and shows the temperature measurement by the optical fiber measuring device in preparation of the ground improvement body by chemical | medical solution injection | pouring. FIG. 9 is a perspective view illustrating a configuration of a distal end portion of a measuring rod according to a third embodiment.

  EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated using drawing. However, although various technically preferable limitations for implementing the present invention are given to the embodiments described below, the scope of the invention is not limited to the following embodiments and illustrated examples.

(Embodiment 1)
FIG. 1 is a diagram showing a construction status of the quality control method for a ground improvement body according to the present embodiment, and FIG. 2 is a cross-sectional view taken along the line II-II shown in FIG. The cross section of the ground improvement body 5 is shown.

  The quality control method for the ground improvement body according to the present embodiment is a method for confirming the shape typified by the diameter of the ground improvement body in real time when creating the ground improvement body by the high-pressure jet stirring method. With reference to FIG.1 and FIG.2, each apparatus for performing the quality control method which concerns on this embodiment is demonstrated.

  On the ground, a creation device 1 for creating a ground improvement body is installed, and a management device 2 for performing quality control of the ground improvement body is installed. The generating device 1 includes a main body 11 and an injection rod 12 supported by the main body 11. The injection rod 12 extends in the vertical direction, is supported in a state that it can move in the vertical direction and can rotate about the vertical direction. An injection hole 13 is formed in the side surface of the tip of the injection rod 12, and the curable material liquid 6 is injected from the injection hole 13 toward the side of the injection rod 12 at a high pressure. The curing material liquid 6 is a liquid curing material such as cement milk. The ground is cut by the high-pressure jetted hardened material liquid 6, and the ground and the hardened material liquid 6 that have been cut are mixed by stirring, whereby the cylindrical ground improvement body 5 is formed. The liquid ejected from the ejection hole 13 at a high pressure is not limited to the curable material liquid 6, and may be water or the like.

The management apparatus 2 includes optical fiber measuring devices 21 to 23, a data logger 24, a monitor 25, and the like. As for the optical fiber measuring devices 21-23, the base end part side is connected to the data logger 24, and the front-end | tip part side is installed in the ground. The optical fiber measuring devices 21 to 23 can sense temperature, strain, etc. at any point on the surface, and can simultaneously measure a plurality of locations in the ground. As shown in FIG. 2, the tip end sides of the optical fiber measuring devices 21 to 23 are arranged side by side along the radial direction of the ground improvement body 5. That is, the optical fiber measuring device 22 is disposed on the outer peripheral edge of the ground improvement body 5, the optical fiber measuring device 21 is disposed on the inner side, and the optical fiber measuring device 22 is disposed on the outer side. The data logger 24 records and stores the measurement results of the optical fiber measuring devices 21 to 23, and the monitor 25 displays the history of the measurement results on the screen.
In addition, the arrangement | positioning by the side of the front-end | tip part of the optical fiber measuring devices 21-23 may not be arranged along the radial direction of the ground improvement body 5, and may mutually be arrange | positioned and shifted | deviated. Further, the number of optical fiber measuring devices provided is not limited to three, but may be one or two, or four or more.

Then, the quality control method of the ground improvement body which concerns on this embodiment is demonstrated.
In this embodiment, the case where the cylindrical ground improvement body 5 is created at a predetermined depth by the high-pressure jet stirring method will be described. Moreover, the case where the temperature of the ground in which the ground improvement body 5 is created is measured with the optical fiber measuring devices 21-23 as an example of this embodiment is demonstrated.

  First, the ground on which the ground improvement body 5 is to be created is excavated, and three bore holes having a predetermined depth are provided at predetermined intervals in the radial direction of the ground improvement body 5. The drilling depth and interval of the boreholes are appropriately determined according to the measurement range and measurement conditions. For example, the interval between the three boreholes is about 50 cm. Optical fiber measuring devices 21 to 23 are inserted and installed in the boreholes. When the installation of the optical fiber measuring devices 21 to 23 is completed, the temperature of the ground before the ground improvement is measured. And the temperature measurement by the optical fiber measuring devices 21-23 is continued as it is, and is continuously performed during the ground improvement described below.

  Subsequently, the creation device 1 is installed on the ground surface of the ground where the ground improvement body 5 is to be created. And the injection rod 12 is lowered | hung until it reaches a predetermined depth, and the injection rod 12 is installed in the ground. The injection rod 12 can be lowered until the lower end position reaches a depth of typically about 10 to 20 m, and about 100 m at the maximum.

  Next, while rotating the injection rod 12, it is pulled upward by a predetermined length until it reaches a predetermined position, and at the same time, the curable material liquid 6 is injected from the injection hole 13 at a high pressure. The hardened material liquid 6 sprayed at a high pressure cuts the ground around the jet rod 12 with the jet energy, and the ground thus cut and the hardened material liquid 6 are stirred and mixed. Thereby, the ground improvement body 5 is created until the position where the injection rod 12 is pulled up. The diameter of the ground improvement body 5 thus created can be changed as appropriate, and is, for example, 2 to 8 m in diameter.

Here, as described above, the temperature measurement by the optical fiber measuring devices 21 to 23 is continuously performed before the ground improvement body 5 is formed, and is continuously performed during the formation of the ground improvement body 5.
The optical fiber measuring devices 21 to 23 measure thermal energy generated when the jet energy generated by the hardening material liquid 6 cuts the ground. As shown in FIG. 2, since the optical fiber measuring devices 21 and 22 are arranged inside the ground improvement body 5, the optical fiber measurement devices 21 and 22 are cut by the ground improvement body 5 (the hardening material liquid 6 and the hardening material liquid 6. The temperature of the ground is continuously detected. On the other hand, since the optical fiber measuring device 23 is disposed outside the ground improvement body 5, the optical fiber measurement device 23 is formed on the ground around the ground improvement body 5 (the ground cut by the hardened material liquid 6 and the hardened material liquid 6). Sensing temperature continuously. The data logger 24 records and stores the measurement results obtained by the optical fiber measuring devices 21 to 23. The monitor 25 displays a history of measurement results recorded by the data logger 24 on the screen. Further, when the monitor 25 has an arithmetic processing function, the history of the measurement results is displayed, and at the same time, the diameter of the ground improvement body 5 is estimated based on the measurement results by the optical fiber measuring devices 21 to 23, and this is displayed on the screen. It is good also as what is displayed on. The installer can confirm in real time during the formation of the ground improvement body 5 whether or not the ground improvement body 5 is formed with an appropriate diameter by tracking the history of the measurement results displayed on the monitor 25. it can. Thereby, the quality of the ground improvement body 5 can be managed appropriately, and when the ground improvement body 5 is not formed with the target diameter, the builder can cope early.
In the present embodiment, the temperature measured by the optical fiber measuring devices 21 to 23 is not limited to the thermal energy generated at the time of cutting, and the hydration heat of the curable material liquid 6 can also be measured.

The effect of this embodiment is demonstrated.
According to this embodiment, the optical fiber measuring devices 21 to 23 continuously measure the thermal energy generated when the hardened material liquid 6 cuts the ground and track the history of the measurement results, thereby improving the ground improvement body 5. It is possible to confirm in real time whether or not is constructed with an appropriate diameter. Since the shape represented by the diameter of the ground improvement body 5 can be confirmed in real time, the quality of the ground improvement body 5 can be managed appropriately.

In the present embodiment, since an optical fiber measuring instrument is used as the temperature measuring means, the following operational effects are obtained. The function and effect will be described with reference to FIG.
FIG. 3A shows a case where the thermocouple 3 is used as the temperature measuring means, and FIG. 3B shows a case where the optical fiber measuring device 4 is used as the temperature measuring means. The thermocouple 3 is generally configured by covering two types of cables 31 and 32 with a covering material 34 so that the temperature can be sensed at a contact portion 33 where the cables 31 and 32 are in contact with each other. On the other hand, since the optical fiber measuring device 4 can sense the temperature at any point on the surface, the temperature at a plurality of points can be measured with one optical fiber measuring device.

  Further, as shown in FIG. 3A, when the thermocouple 3 is cut during the formation of the ground improvement body 5, the thermocouple 3 senses the temperature at the contact portion 33 as described above. If the cut part is closer to the base end side than the contact part 33, the contact part of the cables 31 and 32 disappears and the temperature cannot be measured. On the other hand, as shown in FIG. 3 (b), even if the optical fiber measuring instrument 4 is cut during the formation of the ground improvement body 5, the temperature is continuously measured on the base end side from the cut portion. Is possible.

  Thus, according to this embodiment, since the optical fiber measuring instrument is used as the temperature measuring means, the temperature at a plurality of points can be measured simultaneously. Further, even when the optical fiber measuring instrument has been cut, the temperature can be continuously measured on the base end side from the cut portion.

In this embodiment, although the optical fiber measuring devices 21-23 shall measure the temperature of a ground, it is good also as what measures the distortion | strain of a ground instead of temperature. In that case, the optical fiber measuring devices 21 to 23 continuously sense the ground strain generated when the hardening material liquid 6 cuts the ground. When measuring temperature, it takes time for the thermal energy generated by cutting the ground to reach the optical fiber measuring instrument 23, which may cause a slight time lag in the measurement result. Such a time lag is unlikely to occur, and the shape represented by the diameter along the real time can be confirmed.
Furthermore, it is good also as what measures both the temperature of a ground and the distortion | strain of a ground with the optical fiber measuring devices 21-23. In such a case, the accuracy of the measurement result can be further improved compared to the case where either one is measured.

  In addition, the quality control method of the ground improvement body by this invention is applicable, for example, even if it is a wall shape, a fan shape, a grid | lattice shape, etc., when a ground improvement body is not cylindrical shape.

(Problem of measuring the range of ground improvement body by chemical injection by temperature measurement using thermocouple)
Conventionally, when measuring the construction range of the ground improvement body created by the chemical injection method, the temperature of the chemical injected at a higher temperature than the ground is detected by comparing the temperature difference between the chemical and the ground. There is a technique for confirming the injection of heat, which uses a thermocouple element that can measure the temperature by using a change in electrical resistance.

  FIG. 4 points out the problem of temperature measurement by the thermocouple of the ground improvement body by chemical injection, 40 is a ground improvement body created by injecting chemical liquid, 41 is a measuring device, 42 is a measuring rod, 43 is a thermocouple, Reference numeral 44 denotes wiring.

  As shown in the figure, a measuring rod 42 including a thermocouple 43 corresponding to the chemical solution injection range of the ground improvement body 40 formed by injecting the chemical solution is previously installed in the ground.

However, in the temperature measurement of the chemical solution by the thermocouple 43, the thermocouple 43 can measure only one place with one element.
For this reason, in order to measure over a wide range, as shown in the figure, a great number of thermocouples 43 must be installed.
Therefore, as shown in the figure, there is a problem that the wiring 44 is very many and complicated.

(Measurement range measurement of ground improvement by chemical injection by temperature measurement using optical fiber measuring instrument)
The present invention performs measurement of a chemical solution injection range using an optical fiber.
That is, a continuous injection optical fiber is placed in the ground, and the temperature of the chemical solution injected at a temperature higher than the ground is measured to measure the injection range of the chemical solution.

  FIG. 5 shows temperature measurement using an optical fiber measuring instrument for ground improvement by chemical injection, 50 is a ground improvement formed by chemical injection, 51 is a measuring device, 52 is a measuring rod, 53 is an optical fiber measuring instrument, 54 Is an optical fiber.

  As shown in the figure, a measuring rod 52 including an optical fiber measuring device 53 corresponding to the chemical solution injection range of the ground improvement body 50 formed by injecting the chemical solution is previously installed in the ground.

  With this optical fiber measuring instrument 53, only one or two optical fibers 54 are required for each measurement point, so that wiring can be simplified.

FIG. 6 is an enlarged view of a specific configuration of the optical fiber measuring device 53. Two optical fibers 54 are cut off from the measuring rod 52 in correspondence with the chemical solution injection range of the ground improvement body 50 formed by injecting the chemical solution. Wrapped without any problems.
One optical fiber 54 may be wound without a break.

(Embodiment 2)
FIG. 7 shows temperature measurement by an optical fiber measuring instrument during the construction of a ground improvement body by chemical injection, 60 is a chemical injection rod, 70 is a ground improvement body formed by chemical injection, 72 is a measurement rod, and 73 is an optical fiber. It is a measuring instrument.

  As shown in the figure, in the step of creating the ground improvement body 70 by injecting the chemical solution from the chemical injection rod 60 inserted into the ground, the optical fiber of the measuring rod 72 previously installed in the ground corresponding to the chemical injection range. The temperature of the ground improvement body 70 under construction is continuously measured by the measuring device 73, and the shape represented by the diameter of the ground improvement body 70 is measured by a measuring device (not shown) on the ground.

  Accordingly, it is possible to directly measure the finished shape of the ground improvement body 70 being created by the chemical solution injection, and to reliably perform the construction management.

(Embodiment 3)
FIG. 8 shows the configuration of the tip of the measuring rod 80, 81 is a chemical solution discharge hole, 82 is a camera, 83 is an optical fiber measuring instrument, and 84 is an optical fiber.

  As shown in the figure, at the tip of the hollow measuring rod 80, a chemical solution discharge hole 81 that opens to the periphery and discharges a chemical solution (for example, a phenol solution) is formed. An optical fiber measuring device 83 wound in a continuous manner is incorporated.

  Here, the wiring of the camera 82 and the optical fiber 84 are connected to a measuring device including a ground monitor (not shown) through the inside of the measuring rod 80.

Thus, by providing the measuring rod 80 with the optical fiber measuring device 83, the injection range can be continuously measured during the injection of the chemical solution into the ground, and the finished shape of the ground improvement body can be measured.
Further, by providing the measuring rod 80 with the camera 82, it is possible to check the state of the chemical liquid injection into the ground with a monitor.

(Modification)
In FIGS. 4, 5 and 7, the spherical ground improvement body is used. However, the present invention is not limited to this, and in addition to the cylindrical shape as shown in FIGS. It can be applied to other shapes.

DESCRIPTION OF SYMBOLS 1 Formation apparatus 2 Management apparatus 5 Ground improvement body created by high-pressure jet 6 Hardening material liquid 12 Injection rod 21 Optical fiber measuring device 22 Optical fiber measurement device 23 Optical fiber measurement device 50 Ground improvement body 51 formed by injecting chemical solution Measurement device 52 Measurement Rod 53 Optical fiber measuring device 54 Optical fiber 60 Chemical solution injection rod 70 Ground improvement body 72 formed by injecting chemical solution Measuring rod 73 Optical fiber measuring device 80 Measuring rod 81 Chemical solution discharge hole 82 Camera 83 Optical fiber measuring device 84 Optical fiber

Claims (6)

It is a quality control method for a ground improvement body that is created by high-pressure jetting of a hardening material liquid from a jet rod penetrating into the ground,
In the ground where the ground improvement body is created, an installation step of installing an optical fiber measuring instrument that measures at least one of temperature and strain in advance,
During the creation of the ground improvement body, at least one of the temperature or strain of the ground on which the ground improvement body is created is continuously measured by the optical fiber measuring instrument, and the history of the measurement results is tracked in real time. A quality control method for a ground improvement body, comprising: a management step for confirming a shape represented by the diameter of the ground improvement body.   The quality control method for a ground improvement body according to claim 1, further comprising a step of measuring the temperature of the ground on which the ground improvement body is created by the optical fiber measuring instrument before the management step.   3. In the management step, during the creation of the ground improvement body, both the temperature and strain of the ground on which the ground improvement body is created are continuously measured by the optical fiber measuring instrument. Quality control method for ground improvement bodies as described in 1. A method for measuring a shape typified by the diameter of a ground improvement body formed by high-pressure jetting of a hardening material liquid from a jet rod inserted into the ground,
Inserting an optical fiber measuring instrument for measuring at least one of temperature and strain into the ground for forming the ground improvement body,
During the formation of the ground improvement body, the shape represented by the diameter of the ground improvement body is obtained by continuously measuring at least one of the temperature or strain of the ground on which the ground improvement body is formed by the optical fiber measuring instrument. A method for measuring a ground improvement body, characterized by measuring A method of measuring a shape represented by the diameter of a ground improvement body created by injecting a chemical into the ground,
Inserting an optical fiber measuring instrument for measuring temperature into the ground for creating the ground improvement body,
During the creation of the ground improvement body, by continuously measuring the temperature of the ground on which the ground improvement body is created by the optical fiber measuring instrument, measuring the shape typified by the diameter of the ground improvement body. A method for measuring a ground improvement body as a feature.   A measuring rod comprising an optical fiber measuring device for measuring the temperature of surrounding ground.

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