Vertical precision measuring device

Abstract

Provided is a vertical accuracy measuring device capable of easily measuring the bending state or inclination state of a tubular body such as a casing pipe buried in the ground and not directly visible from the outside with respect to the axial direction. 【Solution means】The vertical accuracy measuring device 1 includes a measuring weight 10 suspended from a mounting starting point 2 via a string 3 as a linear body and provided so as to be movable along the axial direction on the inner peripheral side of a casing pipe 4 which is a tubular body, and a measuring member 20 which is horizontally suspended by the length from the mounting starting point 2 to the upper side of the casing pipe 4, has an insertion hole through which the string 3 is inserted, and has a scale for identifying the displacement width of the string 3 inserted through this insertion hole with respect to the center in the casing pipe 4, and measures the verticality of the casing pipe 4 based on the identification result of this scale.

Description

Technical Field

[0001] The present invention relates to a vertical accuracy measuring device for measuring the vertical accuracy during casing drilling in, for example, ground improvement methods.

Background Art

[0002] Conventionally, ground improvement methods such as the high-pressure jet mixing method have evolved from countermeasures for soft ground. Therefore, in the driven pile method, there are no concepts of pile cores and vertical accuracy that are managed, and construction management items and measurement methods have been advanced without being fully prepared.

[0003] However, in recent years, the high-pressure jet mixing method has tended to increase in diameter and depth with the increase in construction achievements. In the high-pressure jet mixing method in which high-pressure slurry is injected from the tip of the nozzle to a predetermined improvement range and stirred, there is not only the risk of unimproved parts due to the reduction in diameter of the improvement range (the planned formation diameter is not formed), but also the risk of column-in-column (a state in which a hole is drilled for subsequent construction in the previously constructed body) due to the increase in diameter (a formation diameter larger than planned) or the deviation of the construction core, and the risk of the formation of a shadow of the previously constructed body, resulting in an increased risk of unimproved parts where the planned formation diameter is not formed. Therefore, vertical accuracy management in the high-pressure jet mixing method has become an essential element for ensuring quality.

[0004] As a method for confirming vertical accuracy currently in use, it is a common method to confirm the horizontal state of the boring machine on the ground and the inclination angle of the casing pipe with a level or the like. However, in these methods, when a curvature occurs in the axial direction of the casing pipe itself, a large error may occur in the tip estimation result. In addition, the method for confirming the drilling accuracy using an inserted inclinometer or the like, which is partially implemented, has problems such as complicated procedures, time-consuming, and high measurement costs.

[0005] Conventionally, as a measuring tool for measuring the eccentricity of a pile, there is, for example, the technique described in Patent Document 1. This technique includes a rectangular plate-like member, a rectangular notch formed in the plate-like member with one side slightly larger than the diameter of the pile to be measured, marks indicating the centers of the notches provided on the four sides of the plate-like member, and scales provided around the marks on the four sides of the plate-like member.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] However, since the measuring tool described in Patent Document 1 is not for measuring a pipe buried in the ground but is premised on the outside of the pipe being exposed, there is a problem that it is impossible to measure the bending state or inclination state of a tubular body such as a casing pipe with respect to the axial direction using this measuring tool.

[0008] An object of the present invention is to provide a vertical accuracy measuring device capable of easily measuring the bending state or inclination state of a tubular body such as a casing pipe buried in the ground and having an outer side that cannot be directly visually observed with respect to the axial direction.

Means for Solving the Problems

[0009] To solve the above problems, the invention according to claim 1 of the present invention is a measuring weight suspended from a mounting starting point via a linear body and movably provided along the axial direction of the tubular body on the inner peripheral side of the tubular body only along the axial direction of the tubular body , the movement in the direction perpendicular to the axial direction of the tubular body is restricted and, a scale that is horizontally suspended from the mounting starting point above the tubular body by a plurality of strings and through which the linear body passes, and that identifies the displacement width of the linear body inserted through the insertion hole with respect to the center in the tubular body has a measuring plate, and on this measuring plate in the insertion hole through which the linear body passes, is formed and a scale for identifying the displacement width of the linear body inserted through the insertion hole with respect to the center in the tubular body is provided on the measuring plate, and theA measuring member that measures the verticality of the tubular body based on the identification result of the scale, and is characterized by comprising the same.

[0010] Further, the invention according to claim 2 of the present invention, in addition to the configuration according to claim 1, the measuring weight is provided with a guiding mechanism that guides the measuring weight to be arranged at the central position on the inner peripheral side of the tubular body when moving along the axial direction of the tubular body.

[0011] Further, the invention according to claim 3 of the present invention, in addition to the configuration according to claim 2, the measuring weight is formed in a long shape, and a plurality of the guiding mechanisms are provided in the length direction of the measuring weight.

[0012] Further, the invention according to claim 4 of the present invention, in addition to the configuration according to claim 1, the measurement plate is formed in an annular shape, and the scale is provided on the upper surface.

[0013] Further, the invention according to claim 5 of the present invention, in addition to the configuration according to claim 1, the linear body is provided with scales at regular intervals, and the distance from the attachment starting point to the measurement plate and the distance from the attachment starting point to the measuring weight are configured to be distinguishable.

Advantages of the Invention

[0014] According to the invention described in claim 1 of the present invention, the measuring weight is suspended from the attachment starting point via the linear body, and the measuring weight is provided so as to be movable along the axial direction on the inner peripheral side of the tubular body only and while 、 the movement in the direction perpendicular to the axial direction of the tubular body is restricted from the attachment starting point has a measuring plate horizontally suspended above the tubular body by a plurality of strings, and on this measuring plate the insertion hole through which the linear body passes is formed and a scale for identifying the displacement width of the linear body inserted through the insertion hole with respect to the center in the tubular body is provided on the measuring plate By measuring the verticality of the tubular body based on the identification result of this scale, it becomes possible to easily measure the curved state or inclined state with respect to the axial direction of a tubular body such as a casing pipe buried in the ground and whose outside cannot be directly visually observed.

[0015] Further, according to the invention described in claim 2 of the present invention, in addition to the effects of the invention described in claim 1, since the measuring weight is provided with a guiding mechanism for guiding it to be arranged at the central position on the inner peripheral side of the tubular body when moving along the axial direction of the tubular body, the measuring weight can move accurately and smoothly along the axis of the tubular body.

[0016] Further, according to the invention described in claim 3 of the present invention, in addition to the effects described in claim 2, since the measuring weight is formed in a long shape and a plurality of guiding mechanisms are provided in the length direction of the measuring weight, it is possible to always guide the measuring weight to the axis of the tubular body.

[0017] Further, according to the invention described in claim 4 of the present invention, in addition to the effects described in claim 1, the measurement plate is formed in an annular shape and a scale is provided on the upper surface, so that it is easier for the operator to read the scale and it is possible to easily identify the deviation width of the linear body from the center in the tubular body.

[0018] Further, according to the invention described in claim 5 of the present invention, in addition to the effects of the invention described in claim 1, the linear body is marked with scales at regular intervals, and the distance from the mounting starting point to the measurement plate and the distance from the mounting starting point to the measuring weight are configured to be distinguishable, so that it is possible to measure the curved state and the inclined state with respect to the axial direction of the tubular body more accurately and easily.

Brief Description of the Drawings

[0019]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0020] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0021] [One Embodiment] FIG. 1 is a schematic configuration diagram showing a vertical accuracy measuring device according to an embodiment of the present invention. FIG. 2 is a perspective view showing a state where the measuring weight of the vertical accuracy measuring device in FIG. 1 is inserted into the casing. FIG. 3 is an enlarged plan view showing a state where the measuring weight in FIG. 2 is inserted into the casing. FIG. 4 is a schematic perspective view showing the measuring member of the vertical accuracy measuring device in FIG. 1. FIG. 5 is an enlarged plan view showing the measuring plate of the measuring member in FIG. 4.

[0022] In this embodiment, an example of measuring the vertical accuracy during casing drilling in the high-pressure jet mixing method will be described. Here, the present invention is not limited to the example of measuring the vertical accuracy during casing drilling in the high-pressure jet mixing method, and can be applied to any case where the curved state or inclined state with respect to the axial direction of the tubular body is measured.

[0023] As shown in FIG. 1, the vertical accuracy measuring device 1 includes a measuring weight 10 suspended from a mounting origin 2 via a string 3 as a linear body such as a flexible cotton twisted thread (spider thread), and a measuring member 20 suspended from the mounting origin 2 to the upper side of a cylindrical casing pipe 4 as a tubular body. The casing pipe 4 in this embodiment is, for example, one having a diameter of 100 to 250 mm.

[0024] As shown in FIG. 2, the string 3 is marked with graduations 5 at regular intervals (for example, 1 m), and by the operator reading these graduations 5, the distance from the mounting origin 2 to the measuring member 20 and the distance from the mounting origin 2 to the measuring weight 10 can be distinguished. The mounting origin 2 of the string 3 has the base end portion of the string 3 fixed to a mounting plate 7 installed on a support column or the like having a predetermined height from the ground 6.

[0025] As shown in FIGS. 2 and 3, the measuring weight 10 is provided so as to be movable along the axial direction of the casing pipe 4 on the inner circumferential side of the casing pipe 4. The measuring weight 10 is connected to the string 3 via an iron head 12 at the center position of the upper surface of the weight body 11. The measuring weight 10 is formed in a long shape, and two guide mechanisms 13 are provided in the length (axis) direction thereof. In this embodiment, two guide mechanisms 13 are provided in the length direction of the measuring weight 10, but a plurality of them may be provided.

[0026] These guide mechanisms 13 include three adjusting screws 14 that are screwed together at a predetermined interval (120°) in the circumferential direction of the weight body 11 as shown in FIG. 3, and rollers 15 that are rotatably fixed to the tip ends of these adjusting screws 14 and contact the inner circumferential surface of the casing pipe 4. The roller 15 is formed in a barrel shape corresponding to the curvature of the inner circumferential surface of the casing pipe 4. The roller 15 is rotatably held by a holding member 16, and the holding member 16 is rotatably fixed to the adjusting screw 14.

[0027] In this embodiment, by changing the tightening length of each adjusting screw 14 with respect to the weight body 11, the protruding length of the roller 15 can be changed. Therefore, by adjusting the protruding length of the roller 15, it is possible to arrange the connection position of the string 3 to the iron head 12 on the axis of the casing pipe 4. That is, it is possible to arrange the measuring weight 10 at the center position on the inner circumferential side of the casing pipe 4. Thereby, the measuring weight 10 can always move along the axis of the casing pipe 4 and can also be applied to casing pipes with different diameters.

[0028] In this embodiment, three adjusting screws 14 are used to arrange the measuring weight 10 at the center position on the inner circumferential side of the casing pipe 4. However, the present invention is not limited to this, and three coil springs may be used instead of the three adjusting screws 14 to press the roller 15 against the inner circumferential surface of the casing pipe 4.

[0029] As shown in FIG. 4, the measuring member 20 has a measuring plate 22 that is horizontally and vertically suspended by three strings 21 of the same length so as to reach the upper side of the casing pipe 4. The three strings 21 are made of, for example, cotton twisted yarn (spider thread) having flexibility similar to that of the string 3. The measuring plate 22 is formed in an annular (ring) shape having an outer diameter of, for example, 80 mm, and includes a circular insertion hole 23 of, for example, 40 mm through which the string 3 is inserted. The three strings 21 are connected in the vicinity of the outer peripheral end at a predetermined interval (120°) in the circumferential direction.

[0030] The measuring plate 22 has a scale 24 for identifying the displacement width of the string 3 inserted through the insertion hole 23 with respect to the center in the casing pipe 4, and measures the verticality of the casing pipe 4 based on the identification result of this scale 24. As shown in FIG. 5, for example, a stack scale used in level measurement is applied to the scale 24 of the present embodiment.

[0031] Next, the operation of the vertical accuracy measuring device 1 according to the present embodiment will be described.

[0032] Specifically, in the present embodiment, an example of measuring the verticality of the casing pipe 4 during casing drilling in the high-pressure jet mixing method will be described.

[0033] First, a drilling machine (not shown) is installed, and drilling is performed to an arbitrary depth using the casing pipe 4 and a rotating body for drilling (not shown). After drilling to the arbitrary depth, the rotating body for drilling is separated from the casing pipe 4.

[0034] Next, as shown in FIG. 1, the measuring weight 10 is inserted from the upper end opening of the casing pipe 4, and the measuring weight 10 is lowered along the axial direction on the inner peripheral side of the casing pipe 4 to specify the depth. At this time, the measuring weight 10 is provided with a two-stage guide mechanism 13 in the length (axial) direction in the casing pipe 4, so that the measuring weight 10 can be arranged at the central position on the inner peripheral side of the casing pipe 4. As a result, the measuring weight 10 can move along the axis of the casing pipe 4. Further, since the scale 5 is attached to the string 3 at regular intervals as described above, the operator can identify the distance from the attachment starting point 2 to the measuring weight 10.

[0035] Then, the measuring member 20 is connected to the attachment starting point 2 via three strings 21. Specifically, the measuring member 20 is suspended by three strings 21 so that the distance L1 from the attachment starting point 2 to the measuring member 20 is, for example, 2 m.

[0036] Also, the measuring weight 10 is connected to the attachment starting point 2 so that the distance L2 from the measuring plate 22 of the measuring member 20 to the measuring weight 10 is, for example, 30 m. That is, the measuring weight 10 is suspended by the string 3 so that the distance L2 from the measuring plate 22 to the vicinity of the lower end of the casing pipe 4 is, for example, 30 m.

[0037] Then, the operator identifies the XY-direction coordinates of the string 3 with respect to the scale 24 of the measuring plate 22. In the example shown in FIG. 5, since it is displaced +7.5 mm (X1) in the X direction and +7.5 mm (Y1) in the Y direction from the position of the center O of the measuring plate 22, it is displaced 7.9 mm from the position of the center O of the measuring plate 22 based on the dimensional relationship of the right-angled isosceles triangle. Here, when the displacement width in the X direction from the center O of the measuring plate 22 and the displacement width in the Y direction from the position of the center O of the measuring plate 22 are different, it is possible to calculate the displacement width from the position of the center O of the measuring plate 22 based on the Pythagorean theorem. In the present embodiment, the combined displacement width in the X and Y directions is calculated, but it may be calculated as the displacement amounts independent of each other in the X and Y directions.

[0038] As a result, since the distance L1 from the attachment starting point 2 to the measuring member 20 is 2 m, when the distance L1 is 2 m, there is a deviation width of 7.9 mm from the position of the center O of the measuring plate 22. Therefore, when the distance L2 is 30 m, it can be calculated by the proportional relationship that the deviation at the plane position near the lower end of the casing pipe 4 is 118.5 mm.

[0039] By repeating the above measurement operation at an arbitrary depth of the measuring plumb bob 10 for which the vertical accuracy is to be measured in this way, it becomes possible to sequentially measure the curved state and the inclined state of the casing pipe 4 with respect to the axial direction.

[0040] Thus, according to the present embodiment, the measuring plumb bob 10 is suspended from the attachment starting point 2 via the string 3, and this measuring plumb bob 10 is axially provided on the inner peripheral side of the casing pipe 4 only so as to be movable along while , the movement in the direction perpendicular to the axial direction of the casing pipe 4 is restricted from the attachment starting point 2 has a measuring plate 22 horizontally suspended above the casing pipe 4 by a plurality of strings 21, and this measuring plate 22 has an insertion hole 23 through which the string 3 is inserted, and has a scale 24 for identifying the deviation width of the string 3 inserted through the insertion hole 23 with respect to the center in the casing pipe 4. By measuring the verticality of the casing pipe 4 based on the identification result of this scale 24, it becomes possible to easily measure the curved state and the inclined state of the casing pipe 4 with respect to the axial direction, which is buried underground and whose outside cannot be directly visually observed.

[0041] Further, according to the present embodiment, since a guiding mechanism 13 is provided to guide the measuring plumb bob 10 so as to be disposed at the center position on the inner peripheral side of the casing pipe 4 when the measuring plumb bob 10 moves along the axial direction of the casing pipe 4, the measuring plumb bob 10 can move accurately and smoothly along the axis of the casing pipe 4.

[0042] Further, according to the present embodiment, since the measuring plumb bob 10 is formed in a long shape and two guiding mechanisms are provided in the length direction of the measuring plumb bob 10, it becomes possible to always guide the measuring plumb bob 10 along the axis of the casing pipe 4. As a result, it becomes possible to accurately and easily measure the curved state and the inclined state of the casing pipe 4 with respect to the axial direction.

[0043] Also, according to the present embodiment, since the measuring plate 22 of the measuring member 20 is formed in an annular shape and the scale 24 is provided on the upper surface, it becomes easier for the operator to read the scale 24, and the deviation width of the string 3 from the center in the casing pipe 4 can be easily identified.

[0044] Also, according to the present embodiment, scales are attached to the string 3 at regular intervals, and the distance from the attachment starting point 2 to the measuring member 20 of the measuring plate 22 and the distance from the attachment starting point 2 to the measuring weight 10 are configured to be distinguishable. Therefore, it is possible to measure the curved state and inclined state of the casing pipe 4 in the axial direction more accurately and easily.

[0045] [Other Embodiments of the Invention] Although one embodiment of the present invention has been described, this embodiment is presented as an example and is not intended to limit the scope of the invention. This embodiment can be implemented in various other forms, and various omissions, replacements, changes, and combinations can be made without departing from the gist of the invention. This embodiment is included in the scope and gist of the invention, as well as in the invention described in the claims and its equivalent scope.

[0046] In the above-described embodiment, an example in which the string 3 such as a cotton twisted thread (octopus thread) is used as the linear body has been described. However, not limited to the string 3, for example, in addition to metal wires such as piano wires and wires that are stronger and more water-resistant than the string 3, a twisted wire made of resin such as polyethylene without elongation may be used.

[0047] Also, in the above-described embodiment, an example in which a staff scale used in level measurement is applied to the scale 24 for identifying the deviation width of the string 3 from the center in the casing pipe 4 has been described. However, without being limited to this, for example, if a gauge that can slide in the XY direction is provided and it is possible to identify in which direction and by how much distance the string 3 is deviated from the center in the casing pipe 4, any such thing may be used.

Explanation of Reference Numerals

[0048] 1 Vertical precision measuring device 2 Mounting starting point 3 String (linear body) 4 Casing pipe (tubular body) 5 Scale 6 Ground 7 Mounting plate 10 Measuring weight 11 Weight body 12 Iron head 13 Guide mechanism 14 Adjusting screw 15 Roller 16 Holding member 20 Measuring member 21 String 22 Measuring plate 23 Insertion hole 24 Scale L1 Distance L2 Distance O Center

Claims

1. a measurement weight that is suspended from an attachment starting point via a linear body and is provided on an inner peripheral side of the tubular body so as to be movable only along the axial direction of the tubular body, and whose movement in a direction perpendicular to the axial direction of the tubular body is restricted; a measuring member having a measuring plate suspended horizontally above the tubular body by a plurality of strings from the attachment starting point, the measuring plate having an insertion hole through which the linear body is inserted, the measuring plate having a scale for identifying a positional deviation of the linear body inserted into the insertion hole from the center of the tubular body, and measuring the verticality of the tubular body based on the identification result of the scale; A vertical accuracy measuring device comprising:

2. 2. The vertical accuracy measuring device according to claim 1, further comprising a guide mechanism for guiding the measurement weight so that the measurement weight is positioned at a central position on the inner circumference side of the tubular body when the measurement weight moves along the axial direction of the tubular body.

3. 3. The vertical accuracy measuring device according to claim 2, wherein the measurement weight is formed to be long, and a plurality of the guide mechanisms are provided in the longitudinal direction of the measurement weight.

4. 2. The vertical accuracy measuring device according to claim 1, wherein the measuring plate is formed in an annular shape, and the scale is provided on an upper surface thereof.

5. The vertical accuracy measuring device according to claim 1, characterized in that the linear body is marked with scales at regular intervals, so that the distance from the mounting starting point to the measurement plate and the distance from the mounting starting point to the measurement weight can be distinguished.

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