CN110088403B - High-pressure spray nozzle device and foundation improvement device provided with same - Google Patents

Abstract

In the conventional ground improvement device, since the curing material liquid is sent from the curing material liquid supply pipe in the axial direction of the injection rod to the curing material liquid injection nozzle substantially orthogonal to the axis of the injection rod, a part of the flow of the curing material liquid becomes turbulent, and the injection distance of the curing material liquid injected from the curing material liquid injection nozzle becomes short. The turbulent state of the cement slurry is destroyed by finely dividing the cement slurry by a flow path dividing part (31x) of a rear end inner diameter part (28x) of a nozzle main body part (24x), and the cement slurry is fluidized by a finer stratum while the flow rate distribution is uniformized in each divided space. This further increases the cutting ability of the cement slurry injected from the tip of the nozzle body (24x), and thus the cement slurry can be injected over a longer distance.

Description

High-pressure spray nozzle device and foundation improvement device provided with same

Technical Field

The present invention relates to a high-pressure injection nozzle device which communicates with a solidified material liquid supply pipe in an injection rod and is provided on a side surface of a tip forming device connected to a tip of the injection rod, and a ground improvement device to which the high-pressure injection nozzle device is attached.

Background

Conventionally, a ground improvement device has been known in which an injection rod is inserted into an excavation hole of a drilled hole in a ground, and a solidification material liquid is sprayed from a nozzle attached to a distal end side surface of the injection rod in a direction perpendicular to an axial direction of the injection rod.

As shown in fig. 32, the ground improvement apparatus is provided with a jet port 107 in a lower end side wall 101a of an injection rod 101 having a double-pipe structure including a solidification material supply pipe 108 and a compressed air supply pipe 109. The injection port 107 is composed of a discharge port of a curing material liquid injection nozzle 110 communicating with a curing material liquid supply pipe 108 of the injection rod 101, and a compressed air injection nozzle 111 surrounding the curing material liquid injection nozzle 110 and communicating with a compressed air pressure pipe 109. Then, a curing material liquid is supplied from the upper portion of the injection rod 101 through a curing material liquid supply pipe 108, and the curing material liquid is ejected from a curing material liquid ejection nozzle 110 (for example, patent document 1). Here, fig. 32 is a front sectional view of the conventional injection rod.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 10-331151

Disclosure of Invention

Technical problem to be solved by the invention

However, in the conventional ground improvement device, since the curing material liquid is sent from the curing material liquid supply pipe 108 in the axial direction of the injection rod 101 to the curing material liquid injection nozzle 110 substantially orthogonal to the axis of the injection rod 101, a part of the flow of the curing material liquid becomes a swirling flow in a portion where the curing material liquid is sent from the curing material liquid supply pipe 108 to the curing material liquid injection nozzle 110, that is, a curved portion of the pipe, and a part of the flow of the curing material liquid becomes a turbulent flow in front of the curing material liquid injection nozzle 110, and a power loss of the curing material liquid injected from the curing material liquid injection nozzle 110 occurs due to disturbance of the flow of the curing material liquid flowing inside the curing material liquid injection nozzle 110 and a difference in flow rate between the inner peripheral portion and the central portion of the curing material liquid injection nozzle 110. As described above, if a power loss of the curing material liquid ejected from the curing material liquid ejection nozzle 110 occurs, there is a problem that the cutting ability of the curing material liquid ejected from the curing material liquid ejection nozzle 110 deteriorates and the ejection distance becomes short.

As described above, in the conventional ground improvement device, since the ejection distance is shortened by the power loss of the curing material liquid ejected from the curing material liquid ejection nozzle, in order to eliminate this problem, the ejection time of the curing material liquid ejected from the curing material liquid ejection nozzle is lengthened or the interval for lifting the injection rod upward is shortened, thereby improving a wide ground. However, if a wide range of foundations is improved by such a method, the construction period of the foundation improvement work is prolonged, and the construction efficiency is also lowered, and as a result, the construction cost of the foundation improvement work is also increased. In addition, as a method of ejecting the curing material liquid from the curing material liquid ejecting nozzle to a remote place, there is a method of increasing the supply pressure of the curing material liquid supplied to the curing material liquid ejecting nozzle, but in this method, since the curing material liquid is supplied to the injection rod or the curing material liquid ejecting nozzle at a high pressure, the consumption of peripheral equipment becomes severe, and there is a possibility that a problem of improving the ground is caused by the consumption.

As shown in fig. 7 described later, the outlet diameter d of the spray nozzle, the length L of the tip end of the spray nozzle in the same diameter portion, the length LL of the entire spray nozzle, and the throttle angle B from the rear end of the spray nozzle to the tip end of the spray nozzle in the same diameter portion are known, and if the following relational expression is satisfied, the solidified material liquid can be sprayed from the spray nozzle to a long distance. Here, fig. 7 is a drawing of embodiment 1 of the present invention, and the description will be given only with attention paid to the injection nozzle.

[ number 1]

L ═ 3d to 4d (equation 1)

[ number 2]

LL is 15d to 20d (equation 2)

[ number 3]

B12 to 13 degrees (equation 3)

In recent years, there has been a great demand for forming underground consolidated bodies with a large diameter, and in order to form such underground consolidated bodies with a large diameter, it is necessary to increase the outlet diameter d of the injection nozzle. However, if the outlet diameter d of the spray nozzle is increased, it is necessary to increase the length L of the same diameter portion of the tip of the spray nozzle or the length LL of the entire length of the spray nozzle in order to satisfy the relational expressions of equations 1 to 3, and there is a problem that the tip increases the size of the outer shape of the apparatus. Further, if the outer shape of the apparatus is increased by the tip, the injection rod is also increased in size, and the weight of the entire injection rod is increased, and a drill or the like supporting the injection rod is also increased in size, which causes a problem that the construction cost for improving the foundation is also increased.

The present invention has been made in view of the above problems, and an object thereof is to provide a high-pressure jetting nozzle device capable of jetting a curing material liquid from a high-pressure jetting nozzle to a remote place, and a ground improvement device to which the high-pressure jetting nozzle device is attached.

Solution for solving the above technical problem

In order to solve the above problems and achieve the above object, a high-pressure spray nozzle device according to claim 1 of the present invention is a high-pressure spray nozzle device which communicates with a solidified material liquid supply pipe formed in an axial direction in an injection rod and is provided on a side surface of a tip forming device connected to a tip of the injection rod, the high-pressure spray nozzle device including a nozzle main body portion formed in a hollow shape, the nozzle main body portion including a conical intermediate inner diameter portion having an inner peripheral surface formed by reducing a diameter in a direction toward the tip; a front end inner diameter portion which communicates with the front end of the intermediate inner diameter portion and has a diameter substantially the same as the diameter of the front end of the intermediate inner diameter portion; a rear end inner diameter portion which communicates with a rear end of the intermediate inner diameter portion, is formed to have a diameter substantially the same as a rear end diameter of the intermediate inner diameter portion or to be expanded from the substantially same diameter in a rear end direction, and has a flow path dividing portion which divides a hollow shape into a plurality of spaces formed in a rear end inner diameter portion of the nozzle body portion, the flow path dividing portion including: in the substantially central portion of the rear end inner diameter portion of the hollow shape near the flow path dividing portion, the solidified material liquid flowing in the rear end inner diameter portion of the nozzle main body portion is fluidized more finely in each space divided by the flow path dividing portion, and then is reduced in diameter and transported in the front end direction in the hollow shape space of the intermediate inner diameter portion where no shaped material is present, so that the cutting ability of the solidified material liquid ejected from the front end inner diameter portion of the nozzle main body portion is increased, and the solidified material liquid can be ejected further away.

When the direction of the solidified material liquid is changed from the direction of the solidified material liquid supply pipe in the injection rod toward the direction of the hollow shape of the nozzle main body in the front end forming device (monitor), a part of the flow of the solidified material liquid becomes a swirling flow at the bent portion of the pipe and a part of the flow of the solidified material liquid becomes a turbulent state near the nozzle main body, but according to the present invention, the solidified material liquid flowing at the substantially central portion of the rear end inner diameter portion of the nozzle main body collides with the substantially central portion of the flow path dividing portion, and the solidified material liquid flowing at the substantially central portion of the rear end inner diameter portion after the collision flows into each of the flow paths divided by the flow path dividing portion, and the speed increases and is transported toward the inner peripheral surface of the intermediate inner diameter portion formed by reducing the diameter, so that the thickness of the boundary layer of the turbulent flow generated at the inner peripheral surface of the intermediate inner diameter portion can be reduced, the layer fluidization can be more finely performed. Thus, the cutting ability of the solidified material liquid ejected from the material liquid ejection nozzle at the tip of the nozzle body is increased, whereby the structure of the ground can be destroyed and the solidified material liquid can be ejected at a longer distance. That is, since the thickness of the boundary layer of the turbulent flow generated in the inner peripheral surface of the intermediate inner diameter portion can be reduced, the solidified material liquid ejected from the ejection opening of the material liquid ejection nozzle at the tip of the nozzle main body portion is ejected at substantially the same speed over substantially the entire surface of the ejection opening. This makes it possible to extend the region (constant velocity core region) where the speed of the curing material liquid ejected from the ejection port of the material liquid ejection nozzle at the tip of the nozzle body does not decrease, and to eject the curing material liquid at a longer distance.

The invention according to claim 2 is the high-pressure injection nozzle device according to claim 1, wherein the total cross-sectional area of the flow paths divided by the flow path dividing portion is 40% to 60% of the hollow cross-sectional area of the rear end inner diameter portion in the vicinity of the flow path dividing portion.

According to the present invention, since the total cross-sectional area of the flow paths divided by the flow path dividing portion is 40% to 60% of the hollow cross-sectional area of the rear end inner diameter portion in the vicinity of the flow path dividing portion, the solidified material liquid flowing in the rear end inner diameter portion of the nozzle body is distributed to each space divided by the flow path dividing portion, and is conveyed in the front end direction while being compressed by an appropriate compression force. This makes it possible to further accelerate the flow rate of the solidified material liquid in each of the spaces divided by the flow path dividing portion 31 and to fluidize the solidified material liquid finely, and to increase the cutting ability of the solidified material liquid injected from the material liquid injection nozzle 21 at the tip of the nozzle body 24, thereby breaking the structure of the ground and injecting the solidified material liquid at a further distance.

The 3 rd aspect of the present invention is the high-pressure injection nozzle device according to the 1 st or 2 nd aspect, wherein the hollow cross-sectional area in the vicinity of the flow path dividing portion is the hollow cross-sectional area immediately upstream of the flow path dividing portion.

The 4 th aspect of the present invention is the high-pressure injection nozzle device according to the 1 st or 2 nd aspect, wherein the hollow cross-sectional area in the vicinity of the flow path dividing portion is a hollow cross-sectional area immediately downstream of the flow path dividing portion.

The 5 th aspect of the present invention is the high-pressure injection nozzle device according to any one of the 1 st to 4 th aspects, wherein the flow path dividing portion is formed in a cross shape.

According to the present invention, since the flow path dividing portion is formed in a cross shape, the solidified material liquid flowing through the substantially central portion of the rear end inner diameter portion of the nozzle body collides with the substantially central portion of the cross shape of the flow path dividing portion, and the solidified material liquid in the substantially central portion of the rear end inner diameter portion after the collision uniformly flows into the respective flow paths divided by the cross shape flow path dividing portion, and is accelerated and conveyed toward the inner peripheral surface of the intermediate inner diameter portion formed by reducing the diameter. This can reduce the thickness of the boundary layer of the turbulent flow generated on the inner peripheral surface of the intermediate inner diameter portion, and thus can perform more fine stratification. Thus, the cutting ability of the solidified material liquid ejected from the material liquid ejection nozzle at the tip of the nozzle body is increased, whereby the structure of the ground can be destroyed and the solidified material liquid can be ejected at a longer distance.

The 6 th aspect of the present invention is the high-pressure spray nozzle device according to any one of the 1 st to 5 th aspects, wherein the rear end inner diameter portion of the nozzle body is provided so as to protrude into a solidified material liquid flow path formed at the front end in the axial direction in the device.

According to the present invention, since the rear end inner diameter portion of the nozzle body is provided so as to protrude into the solidified material liquid flow path in the apparatus, the straight distance of the solidified material liquid flowing in the nozzle body can be increased, the occurrence of turbulence can be minimized, the cutting ability of the solidified material liquid ejected from the front end of the nozzle body can be increased, and the solidified material liquid can be ejected at a long distance.

The invention according to claim 7 is a ground improvement device comprising a tip end forming device to which the high-pressure injection nozzle device according to any one of claims 1 to 5 is attached.

Effects of the invention

According to the high-pressure injection nozzle device of the present invention, the solidified material liquid flowing through the substantially central portion of the rear end inner diameter portion of the nozzle body collides with the substantially central portion of the passage dividing portion, and the solidified material liquid flowing through the substantially central portion of the rear end inner diameter portion after the collision flows into each of the passages divided by the passage dividing portion and is transported toward the inner circumferential surface of the intermediate inner diameter portion formed by reducing the diameter while increasing the speed, so that the thickness of the turbulent boundary layer generated on the inner circumferential surface of the intermediate inner diameter portion can be reduced, and the laminar flow can be performed more finely. Thus, the cutting ability of the solidified material liquid ejected from the material liquid ejection nozzle at the tip of the nozzle body is increased, whereby the structure of the ground can be destroyed and the solidified material liquid can be ejected at a longer distance.

Drawings

Fig. 1 is a view showing a construction state of a soil improvement device to which a high-pressure injection nozzle according to embodiment 1 of the present invention is attached.

Fig. 2(a) is an external perspective view showing a front end-forming device to which the high-pressure spray nozzle device is attached. Fig. 2(b) is a view showing a coupling pin for coupling the injection rod to the distal end causing device.

Fig. 3 is a sectional view a-a of fig. 2.

Fig. 4(a) is an enlarged view of a portion P-P of fig. 3. Fig. 4(b) is a view showing a nozzle body mounting hole of the leading end forming device.

Fig. 5 is a diagram showing components of a high-pressure spray nozzle device according to embodiment 1 of the present invention.

Fig. 6 is a sectional view of the constituent parts.

Fig. 7 is a diagram showing the dimensions of the high-pressure jetting nozzle device according to embodiment 1 of the present invention.

Fig. 8 is a sectional view B-B of fig. 3.

Fig. 9 is a cross-sectional view C-C of fig. 3.

Fig. 10 is a diagram illustrating an assembly method of the high-pressure spray nozzle device and peripheral devices thereof according to embodiment 1 of the present invention.

Fig. 11 is a diagram illustrating a method of mounting the high-pressure spray nozzle device.

Fig. 12(a) is an enlarged view of a portion P-P of fig. 3 of the high-pressure spray nozzle device according to embodiment 2 of the present invention. Fig. 12(b) is a view showing a nozzle body mounting hole of the tip forming device.

Fig. 13 is a diagram showing components of a high-pressure spray nozzle device according to embodiment 2 of the present invention.

Fig. 14 is a sectional view of the constituent parts.

Fig. 15 is a sectional view of the high-pressure spray nozzle device mounted on the front end generating device.

Fig. 16 is an enlarged view of a portion P-P of fig. 3 of the high-pressure spray nozzle device according to embodiment 3 of the present invention. Fig. 16(b) is a view showing a nozzle body mounting hole of the tip forming device.

Fig. 17 is a diagram of components of a high-pressure spray nozzle device according to embodiment 3 of the present invention.

Fig. 18 is a sectional view of the constituent parts.

Fig. 19 is a sectional view of a high-pressure spray nozzle device mounted on a front end forming device.

Fig. 20 is a view showing a nozzle body attached to a downward nozzle body attachment hole in modification 1 of the present invention.

Fig. 21 is a view showing a nozzle body attached to an upward nozzle body attachment hole in modification 2 of the present invention.

Fig. 22 is a view showing a flow path dividing portion formed in the rear end inner diameter portion inside the extension portion of the nozzle body according to modification 3 of the present invention.

Fig. 23(a) is a view showing the mounting position of the high-pressure spray nozzle device according to modification 4 of the present invention. Fig. 23(b) is a sectional view showing the device mounting position at the tip of the high-pressure spray nozzle device according to modification 4 of the present invention.

Fig. 24 is a view showing a flow path closing material attached to the nozzle body attachment hole 23 of modification 5 of the present invention.

Fig. 25(a) is an enlarged view of a portion P-P in fig. 3 according to modification 6 of the present invention. Fig. 25(b) is a view showing a nozzle body mounting hole of the tip forming device.

Fig. 26 is a diagram showing components of a high-pressure injection nozzle device according to modification 6 of the present invention.

Fig. 27 is a sectional view of the constituent parts.

Fig. 28(a) is an enlarged view of a portion P-P in fig. 3 of a high-pressure spray nozzle device according to modification 8 of the present invention. Fig. 28(b) is a view showing a nozzle body mounting hole of the tip forming device.

Fig. 29 is a diagram showing components of the high-pressure spray nozzle device.

Fig. 30 is a sectional view of the constituent parts.

Fig. 31 is a view showing a method of mounting the high-pressure spray nozzle device.

Fig. 32 is a front sectional view of a conventional injection rod.

Detailed Description

(embodiment 1) hereinafter, embodiment 1 of a high-pressure spray nozzle device 1 according to the present invention will be described with reference to the drawings. Fig. 1 is a view showing a construction state of a ground improvement apparatus to which a high-pressure injection nozzle device according to embodiment 1 of the present invention is attached.

As shown in fig. 1, a front end forming device 3 is mounted at the front end of the injection rod 2 in combination. Water (liquid) supplied through the injection rod 2 and the tip formation device 3 is ejected from a tip nozzle 4 provided at the tip of the tip formation device 3, and cement paste (curing material liquid) and air supplied through the injection rod 2 and the tip formation device 3 are ejected from a high-pressure ejection nozzle device 1 provided on the side surface of the tip formation device 3.

The manipulator 5 is a machine that supports the injection rod 2 and moves, rotates, and swings the injection rod 2 up and down. Thus, the injection rod 2 and the tip end mechanism 3 can be moved up and down, rotated, and swung by the manipulator 5.

A rotating ring 6 is attached to the rear end of the injection rod 2. The injection rod 2 is formed of a double-walled pipe, and cement paste or water (liquid) is supplied to the cement paste/water supply passage 7 on the inner side in the injection rod 2, and air is supplied to the air supply passage 8 on the outer side in the injection rod 2 (see fig. 3). In embodiment 1, the cement paste (curing material liquid) supply pipe and the water supply pipe are configured as one supply pipe by using the cement paste/water supply passage 7, but the present invention is not limited thereto, and the cement paste (curing material liquid) supply pipe and the water supply pipe may be configured as separate supply pipes. In the case where the cement slurry (curing material liquid) supply pipe and the water supply pipe are configured as different supply pipes as described above, a multilayer pipe or a perforated pipe such as a 3-layer pipe that separates the cement slurry (curing material liquid) and water may be used. In embodiment 1, the inner side of the injection rod 2 made of a double pipe is defined as the grout/water supply passage 7, and the outer side thereof is defined as the air supply passage 8.

As mentioned above, the front end causes the device 3 to be jointly mounted to the front end of the injection rod 2. Further, a cement slurry-compatible water flow path 9 communicating with the cement slurry-compatible water supply path 7 of the injection rod 2 is axially formed in the center of the front end of the inside of the device 3, and 4 air flow paths 10 communicating with the air supply path 8 of the injection rod 2 are axially formed on the outer peripheral side of the cement slurry-compatible water flow path 9 (see fig. 3 and 8). Details of the air flow path 10 will be described later. In embodiment 1, the cement slurry (curing material liquid) flow path and the water flow path are configured as one flow path using the cement slurry/water flow path 9, but the present invention is not limited thereto, and the cement slurry (curing material liquid) flow path and the water flow path may be configured as different flow paths, respectively.

The rotating ring 6 is connected to supply hoses 14, 15, and 16 for water, air, and cement slurry, which are supplied from a water supply source 11, an air supply source 12, and a cement slurry (curing material liquid) supply source 13, respectively, and supplies the water, air, and cement slurry to an air supply passage 8 and a cement slurry/water supply passage 7 (see fig. 1) provided in the injection rod 2. In this way, the grout, air and water supplied from the water supply source 11, the air supply source 12 and the grout supply source 13 are injected from the nozzle or the like through the supply hoses 14, 15 and 16 → the rotary ring 6 → the supply passages 7 and 8 → the flow passages 9 and 10. Here, water and cement paste are supplied from the water and cement paste supply hoses 14 and 16 to the cement paste/water supply passage 7.

Next, the structure of the injection rod 2 and the tip forming device 3 will be specifically described with reference to fig. 2 to 9. Fig. 2(a) is an external perspective view of a tip end forming device to which a high-pressure spray nozzle device according to embodiment 1 of the present invention is mounted, fig. 2(b) is a view showing a coupling pin for coupling an injection rod and the tip end forming device, fig. 3 is a sectional view taken along a line a-a of fig. 2, fig. 4(a) is an enlarged view of a portion P-P of fig. 3, and fig. 4(b) is a view showing a nozzle body mounting hole of the tip end forming device. Here, in fig. 2(a) and 3, the upper side of the injection rod 2 is not shown.

As shown in fig. 2(a), the injection rod 2 is installed in conjunction with the front end generating device 3 as described above. The coupling of the injection rod 2 and the front end forming means 3 will be described later. Here, as the injection rod 2, a double tube comprising an injection rod outer tube 17 having an outer diameter of 45mm and an inner diameter of 37mm and an injection rod inner tube 18 having an outer diameter of 24mm and an inner diameter of 14mm is used. The injection rod outer tube 17 has a lower portion with an inner diameter of 42mm, a coupling pin insertion hole 19 formed in the lower portion, and a coupling pin injection rod recess 20a (see fig. 10) formed in the lower portion inner surface and having substantially the same diameter as the half outer periphery of the coupling pin 36. The outer diameter of the injection rod inner tube 18 is formed to be 22mm from the upper end of the lower part of the injection rod outer tube 17 having an inner diameter of 42mm toward the lower part. The maximum outer diameter DD of the tip forming device 3 is 68mm, the grout/water flow passage 9 having a diameter of 14mm is formed inside the tip forming device 3, the tip forming device outer tube 17a having an outer diameter of 42mm and an inner diameter of 37mm and the tip forming device inner tube 18a having an outer shape of 24mm and an inner diameter of 14mm are formed on the top of the tip forming device 3, and the air flow passage 10 is formed between the tip forming device outer tube 17a and the tip forming device inner tube 18a (see fig. 3). The air flow path 10 is constituted by a flow path formed between the distal end forming device outer tube 17a and the distal end forming device inner tube 18a, and 4 flow paths communicating with the flow path and formed inside the distal end forming device 3 (see fig. 8). In this way, the air supply passage 7 in the injection rod 2 communicates with the air flow passage 10 in the device 3 at the tip. As described above, the high-pressure injection nozzle device 1 for injecting the cement paste and the air is provided on the side surface of the distal end forming device 3, and the coupling pin distal end forming device recess 20b having substantially the same diameter as the half outer circumference of the coupling pin 36 is formed on the upper portion of the side surface (see fig. 10). Further, a tip nozzle 4 for spraying water (liquid) is provided at the tip of the tip forming device 3. Although the injection rod 2 having a circular cross section with an outer diameter of about 45mm is used in embodiment 1, the present invention is not limited thereto, and an injection rod having a circular cross section with a diameter of about 50mm to 140mm (e.g., about 75 mm) may be used, and in the case of using an injection rod having a circular cross section with a diameter of about 50mm to 140mm (e.g., about 75 mm), the inner diameter of the injection rod inner tube 18 may be set to 14mm to 16 mm. Here, the inner diameter of the injection rod inner tube 18 is determined by the flow rate of the cement slurry flowing in the injection rod inner tube 18. Furthermore, an injection rod having a hexagonal cross section may also be used. The coupling pin 36 is composed of a spring pin 36a and a spring pin 36b (see fig. 2 (b)). The coupling pin 36 is first inserted with the spring pin 36b into the coupling pin insertion hole 19 at the lower part of the injection rod 2, and then the spring pin 36a is pressed into the hollow part of the spring pin 36b inserted into the coupling pin insertion hole 19.

As shown in fig. 3, the high-pressure injection nozzle device 1 is provided with a material liquid injection nozzle 21 for injecting cement paste and an air injection nozzle 22 for injecting compressed air. Specifically, the material liquid ejection nozzle 21 is provided inside the high-pressure ejection nozzle device 1, and the air ejection nozzle 22 is formed outside. As described above, if the cement slurry and the compressed air are injected at high pressure from the high-pressure injection nozzle device 1, the cement slurry is injected from the inside of the high-pressure injection nozzle device 1, the compressed air is injected from the outside (outer circumferential portion) thereof, and an air layer film of the compressed air is formed around the injection flow of the cement slurry, whereby the injection reach distance can be increased as compared with the case of the air layer film without the compressed air.

The material liquid ejection nozzle 21 is formed at the tip of the nozzle body 24 inserted into the nozzle body mounting hole 23 (see fig. 4). Here, as described above, two nozzle body mounting holes 23 are formed at equal intervals on the circumference at positions where the axial heights of the device 3 are different at the tip. In embodiment 1, two nozzle body mounting holes 23 are formed at equal intervals on the circumference at positions where the axial heights of the device 3 are different at the tip ends, but they may not be formed at positions where the axial heights of the device 3 are different at the tip ends, or they may not be formed at positions at equal intervals on the circumference. The number of the nozzle body mounting holes 23 may be 2 or more (preferably 4 or more) instead of 2, or may be 3, 4, 6, or the like, or 1.

In this way, since the plurality of nozzle body mounting holes 23 are formed at positions where the axial height of the device 3 is different at the tip, it is possible to efficiently form a bonded body having various shapes in a short time by mounting the nozzle bodies 24 to the different nozzle body mounting holes 23 depending on the application.

The air injection nozzle 22 is formed by an outer peripheral surface of the nozzle body 24, an inner peripheral surface of the air cap 25, and the like. The compressed air is injected at a high speed from the air injection nozzle 22 through a flow path having a cross-sectional area that decreases from the front end to the front end of the air flow path 10 in the device 3. In embodiment 1, the air injection nozzle 22 is formed by the outer peripheral surface of the nozzle body 24, the inner peripheral surface of the air cap 25, and the like, but is not limited thereto, and any other type of air injection nozzle may be used as long as it is configured to communicate with the air flow passage 10 in the tip formation device 3 so as to surround the periphery of the tip inner diameter portion of the nozzle body 24, and to inject compressed air at high speed by reducing the cross-sectional area from the air flow passage 10 in the tip formation device 3 toward the tip.

The nozzle body 24 is composed of a nozzle body 26 and a nozzle body extension 27 (see fig. 5). In embodiment 1, the nozzle body 26 and the nozzle body extension 27 are both formed of a high-strength material such as cemented carbide. The nozzle body 26 has a cylindrical shape with a smaller diameter at the front portion and a cylindrical shape with a slightly larger diameter at the rear portion. The hollow interior of the nozzle body 24 is formed by a rear end inner diameter portion 28, an intermediate inner diameter portion 29, and a front end inner diameter portion 30 (see fig. 6). Fig. 5 is a diagram showing components of the high-pressure spray nozzle device according to embodiment 1 of the present invention, and fig. 6 is a cross-sectional view of the components. The intermediate inner diameter portion 29 and the front end inner diameter portion 30 are formed in the nozzle body 26, and the rear end inner diameter portion 28 is formed in the nozzle body extension 27. In embodiment 1, the rear end inner diameter portion 28 is formed to have a length of 9mm, the intermediate inner diameter portion 29 is formed to have a length of 15mm, and the distal end inner diameter portion 30 is formed to have a length L of 8mm (see fig. 7). The intermediate inner diameter portion 29 is formed in a conical surface shape in which the inner peripheral surface is reduced in diameter in the distal direction at a throttle angle β of 12 to 20 degrees (preferably 12 to 15 degrees, more preferably 12 to 13 degrees), the distal end inner diameter portion 30 communicates with the distal end of the intermediate inner diameter portion 29, the diameter d of the hollow interior is substantially the same as the diameter of the distal end of the intermediate inner diameter portion 29, and the length L is 2 to 4 times (preferably 3 times) the diameter d of the distal end of the intermediate inner diameter portion 294 times). Here, in embodiment 1, the diameter d of the leading end inner diameter portion 30 is formed to be 2 mm. The rear end inner diameter portion 28 communicates with the rear end of the intermediate inner diameter portion 29, and the diameter of the communicating portion is formed substantially the same as the diameter of the rear end of the intermediate inner diameter portion 29. Here, fig. 7 is a diagram showing the dimensions of the high-pressure injection nozzle device according to embodiment 1 of the present invention. When the nozzle body 24 is attached to the distal end forming device 3, the inside of the cement slurry/water flow path 9 (curing material liquid flow path) in the distal end forming device 3 is protruded by 7 mm. Here, the length of the nozzle body 24 protruding into the cement slurry compatible water passage 9 (curing material liquid passage) in the distal end forming device 3 is half (D/2) the diameter (D) of the cement slurry compatible water passage 9 (curing material liquid passage) in the distal end forming device 3 (see fig. 7 to 9). Here, fig. 8 is a sectional view B-B of fig. 3, and fig. 9 is a sectional view C-C of fig. 3. In embodiment 1, the total length LL (32mm) of the nozzle body 24 is 16 times the diameter d (2mm) of the tip end of the intermediate inner diameter portion 29, but the present invention is not limited thereto, and the total length LL of the nozzle body 24 may be 15 to 20 times the diameter of the tip end of the intermediate inner diameter portion 29, or the total length LL of the nozzle body 24 may be 10 to 20 times the diameter d of the tip end of the intermediate inner diameter portion 29 when the total length LL of the nozzle body 24 cannot be increased. Further, a flow path dividing portion 31 that divides the cross section of the hollow rear end inner diameter portion 28 into a plurality of spaces is formed in the rear end inner diameter portion 28 inside the nozzle body extension portion 27. The flow path dividing portion 31 is formed in a cross shape having a width of 1.5mm, a length of 5.5mm, and a depth of 5.0mm (see fig. 5). The depth of the channel dividing section 31 is not limited to 5.0mm, and may be formed to have a predetermined length. As described above, the cross-shaped flow path dividing portion 31 is provided in the hollow rear end inner diameter portion 28, and the area of the cross-shaped intersecting portion of the flow path dividing portion 31 is 2.25mm²Further, the rear end inner diameter portion 28 in the vicinity of the flow path dividing portion 31 had a hollow cross-sectional area (diameter 5.5mm) of 23.7mm²Therefore, the area of the cross-shaped cross portion was 9.5% of the cross-sectional area of the hollow shape. In this way, the flow path dividing portion 31 has the following shape: near the flow path dividing part 31The substantially central portion of the hollow rear end inner diameter portion 28 of (2) has a portion having an area of substantially 10% of the hollow cross-sectional area in the vicinity of the flow path dividing portion 31. In the present embodiment, the flow path dividing section 31 has a shape of a portion having an area of approximately 10% of the cross-sectional area of the hollow shape in the vicinity of the flow path dividing section 31, but is not limited thereto, and may have a shape of a portion having an area of 2% to 25% (preferably 2% to 20% (more preferably 2% to 15%) of the cross-sectional area of the hollow shape in the vicinity of the flow path dividing section 31.

The total cross-sectional area (9.45 mm) of the flow paths divided by the flow path dividing section 31²) A hollow cross-sectional area (23.7 mm) of the rear end inner diameter portion 28 occupying the vicinity of the flow path dividing portion 31²) 40% of the total. In the present embodiment, the total cross-sectional area of the flow paths divided by the flow path dividing section 31 accounts for 40% of the hollow-shaped cross-sectional area of the rear end inner diameter section 28 in the vicinity of the flow path dividing section 31, but the present invention is not limited thereto, and the total cross-sectional area of the flow paths divided by the flow path dividing section 31 may account for 40% to 60% of the hollow-shaped cross-sectional area in the vicinity of the flow path dividing section 31.

In the present embodiment, the hollow cross-sectional areas of the rear end inner diameter portions 28 immediately upstream and downstream of the flow path dividing portion 31 are the same (5.5mm) in diameter, and therefore the hollow cross-sectional area of the rear end inner diameter portion 28 in the vicinity of the flow path dividing portion 31 is set, but when the hollow cross-sectional areas of the rear end inner diameter portions 28 immediately upstream and downstream of the flow path dividing portion 31 are different in diameter, the application can be made such that "the vicinity of the flow path dividing portion 31" is replaced with "the upstream of the flow path dividing portion 31" or "the downstream of the flow path dividing portion 31".

The nozzle body support 32 is attached from the front outer circumferential surface of the nozzle body 26, has a hexagonal outer circumferential surface at the front end, and has a male screw formed on the rear outer circumferential surface. The air cowl 25 has a hexagonal outer peripheral surface at the distal end thereof, a male screw formed on the intermediate outer peripheral surface, and notches 33 formed at the rear end of the intermediate outer peripheral surface at equal intervals in the circumferential direction (see fig. 5). The notch 33 is provided to secure a flow path of the compressed air when the air cover 25 is attached to the distal end forming device 3. The hollow interior of the air cover 25 is tapered in diameter from the notch 33 toward the distal end (see fig. 6).

Then, the cement slurry supplied through the cement slurry/water supply passage 7 in the injection rod 2 and the cement slurry/water passage 9 in the device 3 at the tip end thereof is fed into the nozzle body 24 in the order of the nozzle body extension 27 → the nozzle body 26, and is ejected from the material liquid ejection nozzle 21 (see fig. 8). The compressed air supplied through the air supply passage 8 in the injection rod 2 and the air flow passage 10 in the distal end mechanism 3 is ejected from the air ejection nozzle 22 (see fig. 8). Here, the air injection nozzle 22 communicates with the two air flow paths 10. As described above, the high-pressure injection nozzle device 1 according to embodiment 1 is configured by: a nozzle body 24 composed of a nozzle body 26 and a nozzle body extension 27; a nozzle body support 32; an air shroud 25.

A differential pressure valve 34 (see fig. 3) is provided below the leading end forming device 3. Then, during drilling, low-pressure water is supplied to the cement paste mixing water flow path 7 of the injection rod 2, and this low-pressure water is discharged from the tip nozzle 4 via the differential pressure valve 34, and after drilling is completed, by supplying cement paste to the cement paste mixing water flow path 7 of the injection rod 2, the differential pressure valve 34 is closed, and cement paste is discharged from the material liquid discharge nozzle 21 (high-pressure discharge nozzle device 1).

Next, a method of assembling the injection rod 2, the distal end forming device 3, and the high-pressure injection nozzle device 1 will be described with reference to fig. 10 and 11. Here, fig. 10 is a diagram showing an assembly method of the high-pressure spray nozzle device and peripheral equipment thereof according to embodiment 1 of the present invention, and fig. 11 is a diagram showing an installation method of the high-pressure spray nozzle device.

As shown in fig. 10, the lower end of the injection rod 2 is first inserted from the front end to the upper part of the upper tube 35 of the device. When the injection rod 2 is inserted, the semicircular injection rod protrusion 44 formed at the lower end of the injection rod outer tube 17 and the semicircular distal end causing device upper tube protrusion 45 formed at the distal end causing the upper portion of the device upper tube 35 are fitted to each other, and the circumferential alignment and attachment of the distal end causing device upper tube 35 and the injection rod 2 are performed. Then, the coupling pin 36 is inserted from the coupling pin insertion hole 19 at the lower part of the injection rod 2, and the coupling pin 36 is fitted into the coupling pin injection rod recess 20a at the lower part of the injection rod inner tube 18 and the coupling pin tip causing device recess 20b at the upper part of the device upper tube 35, whereby the tip causing device 3 is coupled to the injection rod 2. In embodiment 1, the upper and lower portions of the upper ends of the 4 air flow paths 10 formed in the front end forming device upper pipe 35 are described as one body, but the present invention is not limited to this, and the upper and lower portions of the upper ends of the 4 air flow paths 10 formed in the front end forming device upper pipe 35 may be configured separately. By configuring these components separately, 4 air flow paths 10 in the upper pipe 35 of the apparatus, which are formed at the tip end, can be easily formed.

Next, the high-pressure injection nozzle device 1 is mounted in the nozzle body mounting hole 23 formed in the side surface of the device upper tube 35 at the tip (see fig. 11). Specifically, the high-pressure injection nozzle device 1 is attached to the nozzle body attachment hole 23 having the device upper tube 35 at the tip in the following order (1) to (3).

(1) The nozzle body extension 27 is inserted from the rear of the nozzle body 26, and the male screw formed on the outer periphery of the front end of the nozzle body extension 27 is screwed to the female screw formed on the inner periphery of the rear end of the nozzle body 26, whereby the nozzle body extension 27 is attached to the nozzle body 26.

(2) Next, the nozzle body holder 32 is fitted from the distal end direction of the nozzle body 26 to which the nozzle body extension 27 is attached, and in this state, inserted into the nozzle body attachment hole 23. When the nozzle body holder 32 is inserted into the nozzle body mounting hole 23, the nozzle body holder 32 (including the nozzle body 26 and the nozzle body extension 27) is mounted to the distal end effector 3 by screwing the male screw formed on the outer periphery of the rear end of the nozzle body holder 32 into the female screw formed in the nozzle body mounting hole 23 of the distal end effector 3. The nozzle body extension 27 attached in this manner is attached to a substantially central portion of the cement slurry/water passage 9 (curing material liquid passage) in the device 3 at the distal end thereof so as to protrude therefrom (see fig. 7). In other words, the rear end inner diameter portion 28 of the nozzle body 24 attached to the distal end forming device 3 is attached to the substantially central portion (D/2) of the cement slurry/water passage 9 (curing material liquid passage) in the distal end forming device 3 so as to protrude therefrom. Further, in embodiment 1, the rear end inner diameter portion 28 of the nozzle body 24 attached to the distal end effector 3 is attached to protrude from substantially the center of the grout concurrently used water flow path 9 in the distal end effector 3, but the present invention is not limited to this, and may protrude at least substantially 1/3 of the cross section of the grout concurrently used water flow path 9 in the distal end effector 3, or may protrude at least substantially 1/2 to substantially 2/3 (preferably substantially 2/3) of the cross section of the grout concurrently used water flow path 9 in the distal end effector 3 when the plurality of nozzle body attachment holes 23 are formed at positions where the axial heights of the distal end effector 3 are different as in embodiment 1.

(3) Next, the air cap 25 is fitted from the tip direction of the nozzle body 26, and the air cap 25 is attached to the tip end effector 3 by screwing the male screw formed on the outer periphery of the air cap 25 into the female screw formed in the air cap attachment hole 43 on the inner periphery of the side surface of the tip end effector 3.

Next, a head forming device lower pipe 39 incorporating a differential pressure valve 34 is attached to a lower portion of the head forming device upper pipe 35. Specifically, the distal end effector lower tube 39 is attached to the distal end effector upper tube 35 by screwing the male screw of the upper outer periphery of the distal end effector lower tube 39 into the female screw of the lower inner periphery of the distal end effector upper tube 35.

As described above, by providing the rear end inner diameter portion 28 of the nozzle body 24 so as to protrude to the substantially central portion of the cement paste/water passage 9 (curing material liquid passage) in the device 3, the straight distance inside the nozzle body 24 can be sufficiently long, the occurrence of turbulence in the cement paste flowing inside the nozzle body 24 can be reduced, and the cutting ability of the cement paste ejected from the front end of the nozzle body 24 can be increased, whereby the structure of the ground can be destroyed, and the cement paste can be ejected over a long distance. Further, since the total cross-sectional area of the flow paths divided by the flow path dividing section 31 is formed in a shape of 40% of the hollow cross-sectional area of the rear end inner diameter section 28 in the vicinity of the flow path dividing section 31, and the cement slurry flowing through the rear end inner diameter section 28 of the nozzle body 24 is divided into the spaces divided by the flow path dividing section 31 and is compressed by an appropriate compression force and is transported toward the front end direction, the cement slurry can be further accelerated in the spaces divided by the flow path dividing section 31 and fluidized in a fine formation, and the cutting ability of the cement slurry injected from the material liquid injection nozzles 21 at the front end of the nozzle body 24 is increased, thereby breaking the structure of the ground and injecting the cement slurry to a further distance. This is also the case where the total cross-sectional area of the flow paths divided by the flow path dividing section 31 occupies 40% to 60% of the cross-sectional area of the hollow shape in the vicinity of the flow path dividing section 31.

Further, since the cement slurry flowing through the rear end inner diameter portion 28 of the nozzle body 24 is divided into the spaces divided by the flow path dividing portion 31 and is transported in the front end direction, the cement slurry can be fluidized more finely in the spaces divided by the flow path dividing portion 31, and the cutting ability of the cement slurry injected from the material liquid injection nozzle 21 at the front end of the nozzle body 24 is increased, whereby the structure of the ground can be broken, and the cement slurry can be injected at a longer distance. As described in detail above, since the cement slurry flowing through the substantially central portion of the rear end inner diameter portion 28 of the nozzle body 24 collides with the substantially central portion of the flow path dividing portion 31, the cement slurry flowing through the substantially central portion of the rear end inner diameter portion 28 after the collision flows into each of the spaces divided by the flow path dividing portion 31, and is accelerated and transported toward the inner circumferential surface of the intermediate inner diameter portion formed by reducing the diameter, the thickness of the boundary layer of the turbulent flow generated in the inner circumferential surface of the intermediate inner diameter portion can be reduced, and the laminar flow can be performed more finely. This increases the cutting ability of the cement slurry injected from the material liquid injection nozzle 21 at the tip of the nozzle body 24, thereby damaging the structure of the ground and injecting the cement slurry over a longer distance.

As described above, since the male screw formed on the outer peripheral surface of the nozzle body 24 is screwed into the female screw formed on the inner peripheral surface of the nozzle body mounting hole 23 of the distal end effector 3, the nozzle body 24 can be detachably mounted on the distal end effector 3, and therefore the nozzle body 24 can be freely replaced according to the application, and the nozzle body 24 can be mounted on the distal end effector 3 by a simple method.

Next, the construction procedure of the ground improvement device including the tip end forming device to which the high-pressure injection nozzle device according to embodiment 1 of the present invention is attached will be briefly described.

First, after the injection bar 2 is positioned at a position to be excavated, water (liquid) is sprayed from the front end nozzle 4 of the injection bar 2 at the position, and a hole is drilled to a prescribed depth. After drilling to a predetermined depth, the injection rod 2 is swung to inject the cement paste from the material liquid injection nozzle 21 and the compressed air from the air injection nozzle 22. Specifically, the injection rod 2 is swung by 30 degrees (a predetermined angle) while injecting the slurry and the compressed air from the injection nozzles (the material liquid injection nozzle 21 and the air injection nozzle 22).

Next, in a state where the injection lever 2 is swung by 30 degrees, the injection lever 2 is lifted by a predetermined length (for example, 5cm or less (preferably, 2.5 cm); then, the clockwise swing injection → the lifting of the injection lever 2 → the counterclockwise swing injection → the lifting of the injection lever 2 → the clockwise swing injection → the lifting of the injection lever 2 are repeated until the injection from the injection nozzles (the material liquid injection nozzle 21 and the air injection nozzle 22) is completed, and in the embodiment 1, the injection lever 2 is swung, but the injection lever 2 may be rotated in one direction (may be rotated rightward or leftward).

Next, the injection rod 2 is lifted up from the excavation hole by the crane and taken out from the excavation hole. By doing so, a fan-shaped consolidated body is formed in the ground.

(embodiment 2)

Next, embodiment 2 of the high-pressure injection nozzle device according to the present invention will be described with reference to the drawings. Fig. 12(a) is an enlarged view of a portion P-P in fig. 3 of the high-pressure spray nozzle device according to embodiment 2 of the present invention, fig. 12(b) is a view showing a nozzle body mounting hole of the device formed at the tip, and fig. 13 is a view showing components of the high-pressure spray nozzle device according to embodiment 2 of the present invention. Fig. 14 is a sectional view of the constituent parts.

The difference between embodiment 2 of the present invention and embodiment 1 is mainly that in embodiment 1, the nozzle body 26 and the nozzle body extension 27 constituting the nozzle body 24 are configured independently, whereas in embodiment 2, the nozzle body and the nozzle body extension constituting the nozzle body of embodiment 1 are configured integrally, and in embodiment 1, the nozzle body 24 is projected to substantially the center of the grout-compatible water flow path 9 in the tip creating device 3, whereas in embodiment 2, the nozzle body 24x is configured not to project into the grout-compatible water flow path 9 in the tip creating device 3 x. In embodiment 2, the differences from embodiment 1 will be mainly described. In embodiment 2, the same reference numerals are used for the same components (including similar components) as those in embodiment 1, and the description thereof is omitted as components having the same functions and effects.

In the present embodiment, the inner surface portion of the nozzle body 24x and the nozzle body rear member 48x are formed entirely of a high-strength material such as cemented carbide. Here, the nozzle body rear member 48x has a hollow cylindrical shape with a larger diameter at the front portion than at the rear portion of the nozzle body 24x, and a hollow cylindrical shape with a smaller diameter at the rear portion than at the front portion. In the present embodiment, the inner surface of the nozzle body 24x is formed of a high-strength material such as cemented carbide, but the present invention is not limited thereto, and the entire nozzle body 24x may be formed of a high-strength material such as cemented carbide. The outer shape of the nozzle body 24x is a substantially cylindrical shape having a smaller diameter on the front end side of the front portion, a cylindrical shape having a slightly larger diameter in the middle portion than in the front portion, and a cylindrical shape having a slightly larger diameter in the rear portion than in the middle portion. Further, an O-ring mounting recess 47x is formed in the rear end surface of the nozzle body 24x (see fig. 14 (b)).

The hollow interior of the nozzle body 24x is formed by a rear end inner diameter portion 28x, an intermediate inner diameter portion 29x, and a front end inner diameter portion 30x (see fig. 14 b). In embodiment 2, the rear end inner diameter portion 28x is formed to have a length of 5.0mm, the intermediate inner diameter portion 29x is formed to have a length of 5.5mm, and the front end inner diameter portion 30x is formed to have a length of 8.0 mm. The intermediate inner diameter portion 29x is formed in a conical surface shape in which the inner peripheral surface is reduced in diameter in the distal direction at a throttle angle β of 12 to 20 degrees (preferably 12 to 15 degrees, more preferably 12 to 13 degrees), the distal end inner diameter portion 30x communicates with the distal end of the intermediate inner diameter portion 29x, the diameter d of the hollow interior is formed to be substantially the same as the diameter of the distal end of the intermediate inner diameter portion 29x, and the length L is 2 to 4 times (preferably 3 to 4 times) the diameter d of the distal end of the intermediate inner diameter portion 29 x. In embodiment 2, the diameter of the distal end inner diameter portion 30x is formed to be 4.0mm (see fig. 14 (b)). In embodiment 2, the total length LL (18.5mm) of the nozzle body 24x is 4.625 times the diameter d (4mm) of the tip of the intermediate inner diameter portion 29x, but the total length of the nozzle body 24x may be 4 to 20 times the diameter of the tip of the intermediate inner diameter portion 29 x. The rear end inner diameter portion 28x communicates with the rear end of the intermediate inner diameter portion 29x, and the diameter of the inside of the communicating portion is formed substantially the same as the diameter of the rear end of the intermediate inner diameter portion 29 x. When the nozzle body 24x is attached to the distal end effector 3x, the nozzle body 24x is not projected into the cement slurry/water passage 9 (curing material liquid passage) of the distal end effector 3x, and is accommodated in the nozzle body attachment hole 23x of the distal end effector 3 x. Further, a flow path dividing portion 31x that divides the hollow rear end inner diameter portion 28x into a plurality of spaces in cross section is formed in the rear end inner diameter portion 28x at the rear portion of the nozzle body portion 24 x. The flow path dividing section 31x is formed in a cross shape having a width of 2.0mm, a length of 10.0mm, and a depth of 3.5mm (see fig. 13 (b)). The depth of the channel dividing section 31x is not limited to 3.5mm, and may be formed to have a predetermined length. The nozzle body rear member 48x has a length of 6.5mm, communicates with the rear end of the intermediate inner diameter portion 29x, and has a hollow interior diameter substantially equal to the rear end of the intermediate inner diameter portion 29 x. Since the air cap 25x and the nozzle body support 32x are almost the same as those in embodiment 1, descriptions thereof are omitted.

As described above, the cross-shaped flow path dividing portion 3 is provided in the hollow rear end inner diameter portion 28x1x, but the area of the cross-shaped intersecting part of the flow path dividing part 31x was 4.00mm²Further, the rear end inner diameter portion 28x near the flow path dividing portion 31x has a hollow cross-sectional area (diameter 10.0mm) of 78.5mm²Therefore, the area of the cross-shaped intersection portion was 5.1% of the cross-sectional area of the hollow shape. In this way, the flow path dividing portion 31x has the following shape: in the substantially central portion of the rear end inner diameter portion 28x of the hollow shape in the vicinity of the flow path dividing portion 31x, a portion having an area of substantially 5.0% of the cross-sectional area of the hollow shape in the vicinity of the flow path dividing portion 31x is provided. In the present embodiment, the flow path dividing section 31x has a shape of a portion having an area of approximately 5.0% of the cross-sectional area of the hollow shape in the vicinity of the flow path dividing section 31x, but is not limited thereto, and may have a shape of a portion having an area of 2% to 25% (preferably 2% to 20% (more preferably 2% to 15%) of the cross-sectional area of the hollow shape in the vicinity of the flow path dividing section 31x, as described above.

The total cross-sectional area (42.5 mm) of the flow paths divided by the flow path dividing section 31x²) A hollow cross-sectional area (78.5 mm) in the vicinity of the flow path dividing section 31x²) 54.1% of. In the present embodiment, the total cross-sectional area of the flow paths divided by the flow path dividing section 31x is 54.1% of the cross-sectional area of the hollow shape in the vicinity of the flow path dividing section 31x, but as described above, the total cross-sectional area of the flow paths divided by the flow path dividing section 31x may be 40% to 60% of the cross-sectional area of the hollow shape in the vicinity of the flow path dividing section 31 x.

In the present embodiment, the hollow cross-sectional area of the rear end inner diameter portion 28x immediately upstream and downstream of the flow path dividing portion 31x is the same (10.0mm) in diameter, and therefore the hollow cross-sectional area of the rear end inner diameter portion 28x in the vicinity of the flow path dividing portion 31x is set, but when the hollow cross-sectional areas of the rear end inner diameter portions 28x immediately upstream and downstream of the flow path dividing portion 31x are different in diameter, the application can be made such that "the vicinity of the flow path dividing portion 31 x" is replaced with "the upstream of the flow path dividing portion 31 x" or "the downstream of the flow path dividing portion 31 x".

Next, a method of mounting the high-pressure ejection nozzle 1x to the tip end forming device 3x will be described. The difference in the method of mounting the nozzle body 24 in embodiment 1 will be described. Here, fig. 15 is a sectional view of a high-pressure spray nozzle device mounted on the leading end forming device of embodiment 2 of the present invention.

First, the nozzle body rear member 48x is inserted into the nozzle body mounting hole 23x formed in the side surface of the distal end effector 3x (see fig. 12(b) and 15). Here, since the nozzle body extension fixing projection 38x (see fig. 12(b) and 15) is formed in the nozzle body mounting hole 23x formed in the side surface of the distal end forming device 3x of the present embodiment, the rear end of the nozzle body rear member 48x is in contact with the nozzle body extension fixing projection 38x, and the nozzle body rear member 48x is supported by the nozzle body extension fixing projection 38 x.

Next, the nozzle body 24x is inserted into the nozzle body mounting hole 23 x. The rear end of the nozzle body 24x is in contact with the front end side of the nozzle body rear member 48x, but is sealed by an O-ring 46x inserted into an O-ring mounting recess 47x at the rear end of the nozzle body 24 x. The nozzle body rear member 48x (including the nozzle body 24x) thus attached does not protrude into the cement slurry/water passage 9 (curing material liquid passage) in the distal end forming device 3x, and is accommodated in the nozzle body attachment hole 23x of the distal end forming device 3x (see fig. 15).

Next, the air cap 25x is fitted from the tip end direction of the nozzle body 24x, and the high-pressure injection nozzle device 1x including the nozzle body 24x is mounted to the nozzle body mounting hole 23x in the same order as in the mounting order of embodiment 1. The nozzle body rear member 48x (including the nozzle body 24x) mounted in this manner is mounted in a state of being accommodated in the nozzle body mounting hole 23 formed in the tip forming device 3x, unlike the embodiment 1.

As described above, according to the present embodiment, the flow path dividing portion 31x of the rear end inner diameter portion 28x of the nozzle body 24x divides the slurry into fine sections, so that the turbulent state of the slurry is broken, and the slurry is fluidized in a finer stratum while the flow velocity distribution in each of the divided spaces is made uniform. The flow velocity of the fluidized cement slurry is greatly increased while being rectified by the intermediate inner diameter portion 29x of the nozzle body 24x formed by reducing the inner peripheral surface diameter in the distal direction, and the cement slurry having the increased flow velocity is greatly increased linearly in the distal inner diameter portion 30x of the nozzle body 24x, which is substantially the same as the diameter of the distal end of the intermediate inner diameter portion 29x of the nozzle body 24 x. Accordingly, by further increasing the cutting ability of the cement paste ejected from the tip of the nozzle body 24x, the structure of the ground can be destroyed, and the cement paste can be ejected at a longer distance. As described in detail above, since the cement slurry flowing through the substantially central portion of the rear end inner diameter portion 28x of the nozzle body portion 24x collides with the substantially central portion of the flow path dividing portion 31x, the cement in the substantially central portion of the rear end inner diameter portion 28x after the collision flows into each space divided by the flow path dividing portion 31x, and is transported toward the inner circumferential surface of the intermediate inner diameter portion formed by reducing the diameter while increasing the velocity, the thickness of the boundary layer of the turbulent flow generated in the inner circumferential surface of the intermediate inner diameter portion can be reduced, and the formation can be fluidized more finely. Further, since the total cross-sectional area of the flow paths divided by the flow path dividing section 31x is 54.1% of the cross-sectional area of the hollow shape of the rear end inner diameter section 28x in the vicinity of the flow path dividing section 31x, the cement slurry flowing through the rear end inner diameter section 28x of the nozzle body 24x is divided into separate spaces divided by the flow path dividing section 31x and is transported in the front end direction while being compressed by an appropriate compression force, and therefore, the cement slurry can be finely fluidized while further increasing the velocity in each space divided by the flow path dividing section 31x, and the cutting ability of the cement slurry injected from the material liquid injection nozzle 21x at the front end of the nozzle body 24x is increased, whereby the texture of the ground can be broken and the cement slurry can be injected at a further distance. This increases the cutting ability of the cement slurry injected from the material liquid injection nozzle 21x at the tip of the nozzle body 24x, thereby damaging the structure of the ground and injecting the cement slurry over a longer distance. This is also the case where the total cross-sectional area of the flow paths divided by the flow path dividing section 31x occupies 40% to 60% of the cross-sectional area of the hollow shape in the vicinity of the flow path dividing section 31 x. Here, embodiment 2 is also applied to the following modification.

(embodiment 3)

Next, embodiment 3 of the high-pressure injection nozzle device 1y according to the present invention will be described with reference to the drawings. Fig. 16(a) is an enlarged view of a portion P-P in fig. 3 of the high-pressure spray nozzle device according to embodiment 3 of the present invention, fig. 16(b) is a view showing a nozzle body mounting hole of the device formed at the tip, and fig. 17 is a view showing components of the high-pressure spray nozzle device according to embodiment 3 of the present invention. Fig. 18 is a sectional view of the constituent parts.

Embodiment 3 of the present invention differs from embodiment 1 in that, in embodiment 1, the nozzle body extension portion 27y is not extended into the grout-compatible water flow passage 9 of the distal end forming device 3y, rather than the nozzle body extension portion 27 being extended into substantially the center of the grout-compatible water flow passage 9 in the distal end forming device 3. In embodiment 3, the differences from embodiment 1 will be mainly described. In embodiment 3, the same reference numerals are used for the same components (including similar components) as those in embodiment 1, and the description thereof is omitted as components having the same functions and effects.

The nozzle body 24y of the present embodiment is composed of a nozzle body 26y and a nozzle body extension 27y (see fig. 18). In embodiment 3, the inner surface portion of the nozzle body 26y and the nozzle body extension portion 27y are both formed of a high-strength material such as cemented carbide. Further, although the inner surface portion of the nozzle body 26y is formed of a high-strength material such as cemented carbide, the present invention is not limited thereto, and the entire nozzle body 26y may be formed of a high-strength material such as cemented carbide. The nozzle body 26y has a substantially cylindrical shape with a small diameter at the front end, a cylindrical shape with a slightly larger diameter at the middle portion and a slightly larger diameter at the rear portion. An O-ring mounting recess 47y is formed in the rear end surface of the nozzle body 26y (see fig. 18 (b)). The nozzle body extension 27y has a cylindrical shape with a larger diameter at the front portion than at the rear portion of the nozzle body 26y, and a smaller diameter at the rear portion than at the front portion.

The hollow interior of the nozzle body 24y is formed by a rear end inner diameter portion 28y, an intermediate inner diameter portion 29y, and a front end inner diameter portion 30y (see fig. 18). The intermediate inner diameter portion 29y and the tip inner diameter portion 30y are formed in the nozzle body 26y, and the rear end inner diameter portion 28y is formed in the nozzle body extension 27 y. In embodiment 3, the rear end inner diameter portion 28y is formed to have a length of 7.0mm, the intermediate inner diameter portion 29y is formed to have a length of 10.0mm, and the distal end inner diameter portion 30 is formed to have a length of 8.0 mm. The intermediate inner diameter portion 29y is formed in a conical surface shape in which the inner peripheral surface is reduced in diameter in the distal direction at a throttle angle β of 12 to 20 degrees (preferably 12 to 15 degrees, more preferably 12 to 13 degrees), the distal end inner diameter portion 30y communicates with the distal end of the intermediate inner diameter portion 29y, the diameter of the hollow interior is formed to be substantially the same as the diameter of the distal end of the intermediate inner diameter portion 29y, and the length L is 2 to 4 times (preferably 3 to 4 times) the diameter d of the distal end of the intermediate inner diameter portion 29y (see fig. 18). Here, in embodiment 3, the diameter of the leading end inner diameter portion 30y is formed to be 4.0 mm. In embodiment 3, the total length LL (25mm) of the nozzle body 24y is 6.25 times the diameter d (4mm) of the tip of the intermediate inner diameter portion 29y, but the total length LL of the nozzle body 24y may be 6 to 20 times the diameter of the tip of the intermediate inner diameter portion 29 y. The rear end inner diameter portion 28y communicates with the rear end of the intermediate inner diameter portion 29y, and the diameter of the communicating portion is formed substantially the same as the diameter of the rear end of the intermediate inner diameter portion 29 y. When the nozzle body 24y is attached to the distal end effector 3y, the nozzle body 24y is not projected into the cement slurry/water passage 9 (curing material liquid passage) of the distal end effector 3y, and is accommodated in the nozzle body attachment hole 23y of the distal end effector 3 y. Further, a flow path dividing portion 31y that divides the hollow rear end inner diameter portion 28y into a plurality of spaces in cross section is formed in the rear end inner diameter portion 28y inside the nozzle body extension portion 27 y. The flow path dividing section 31y is formed in a cross shape having a width of 2.0mm, a length of 10.0mm, and a depth of 4.5mm (see fig. 17). The depth of the channel dividing section 31y is not limited to 4.5mm, and may be formed to have a predetermined length. Here, the nozzle body support 32y and the air cap 25y are almost the same as those in embodiment 1, and therefore, description thereof is omitted.

As described above, although the cross-shaped flow path dividing portion 31y is provided in the hollow rear end inner diameter portion 28y, the area of the cross-shaped intersecting portion of the flow path dividing portion 31y is 4.00mm²Further, the rear end inner diameter portion 28y near the flow path dividing portion 31y has a hollow cross-sectional area (diameter 10.0mm) of 78.5mm²Therefore, the area of the cross-shaped cross portion was 5.1% of the cross-sectional area of the hollow shape. In this way, the flow path dividing portion 31y has the following shape: the area of the substantially central portion of the hollow rear end inner diameter portion 28y near the channel dividing portion 31y is approximately 5.0% of the area of the hollow cross-sectional area near the channel dividing portion 31 y. In the present embodiment, the flow path dividing section 31y has a shape of a portion having an area of approximately 5.0% of the cross-sectional area of the hollow shape in the vicinity of the flow path dividing section 31y, but is not limited thereto, and may have a shape of a portion having an area of 2% to 25% (preferably 2% to 20% (more preferably 2% to 15%) of the cross-sectional area of the hollow shape in the vicinity of the flow path dividing section 31y, as described above.

The total cross-sectional area (42.5 mm) of the flow paths divided by the flow path dividing section 31y²) A hollow cross-sectional area (78.5 mm) in the vicinity of the flow path dividing section 31y²) 54.1% of. In the present embodiment, the total cross-sectional area of the flow paths divided by the flow path dividing section 31y accounts for 54.1% of the cross-sectional area of the hollow shape in the vicinity of the flow path dividing section 31y, but as described above, the total cross-sectional area of the flow paths divided by the flow path dividing section 31y may account for 40% to 60% of the cross-sectional area of the hollow shape in the vicinity of the flow path dividing section 31 y.

In the present embodiment, the hollow cross-sectional area of the rear end inner diameter portion 28y immediately upstream and downstream of the flow path dividing portion 31y is the same (10.0mm) in diameter, and therefore the hollow cross-sectional area of the rear end inner diameter portion 28y in the vicinity of the flow path dividing portion 31y is set, but when the hollow cross-sectional areas of the rear end inner diameter portions 28y immediately upstream and downstream of the flow path dividing portion 31y are different in diameter, the application of "the vicinity of the flow path dividing portion 31 y" can be replaced with "the upstream of the flow path dividing portion 31 y" or "the downstream of the flow path dividing portion 31 y".

Next, a method of mounting the high-pressure ejection nozzle device 1y on the tip forming device 3y will be described with reference to fig. 19. A description will be given of a method of mounting the nozzle body 24, which is different from that of embodiment 1. Here, fig. 19 is a sectional view of the high-pressure spray nozzle device mounted on the front end forming device.

First, the nozzle body extension 27y is inserted into the nozzle body mounting hole 23y formed in the side surface of the distal end effector 3y (see fig. 19). Here, since the nozzle body extension fixing projection 38y (see fig. 16(b) and 19) is formed in the nozzle body mounting hole 23y formed in the side surface of the distal end forming device 3y of the present embodiment, the rear end of the nozzle body extension 27y is in contact with the nozzle body extension fixing projection 38y, and the nozzle body extension 27y is supported by the nozzle body extension fixing projection 38 y.

Next, the nozzle body 26y is inserted into the nozzle body mounting hole 23 y. Then, the rear end of the nozzle body 26y is in contact with the front end side of the nozzle body extension 27y, but is sealed by the O-ring 46y inserted into the O-ring mounting recess 47y at the rear end of the nozzle body 26 y. The nozzle body extension 27y thus attached is accommodated in the nozzle body attachment hole 23y of the distal end forming device 3y (see fig. 19).

Next, the air cap 25y is fitted from the tip end direction of the nozzle body 26y, and the high-pressure injection nozzle device 1y including the nozzle body 24y is mounted in the nozzle body mounting hole 23y in the same order as in the mounting order of embodiment 1. The nozzle body extension 27y thus attached is attached in a state of being accommodated in the nozzle body attachment hole 23y in the distal end forming device 3y, unlike the embodiment 1.

As described above, according to the present embodiment, the flow path dividing portion 31y of the rear end inner diameter portion 28y of the nozzle body 24y divides the slurry into fine sections, so that the turbulent state of the slurry is broken, and the slurry is fluidized in a finer stratum while the flow rate distribution in each of the divided spaces is made uniform. The flow velocity of the fluidized cement slurry is greatly increased while being rectified by the intermediate inner diameter portion 29y of the nozzle body portion 24y whose inner peripheral surface is reduced in diameter in the distal direction, and the cement slurry whose flow velocity is increased is greatly increased in a straight line in the distal end inner diameter portion 30y of the nozzle body portion 24y which is substantially the same as the diameter of the distal end of the intermediate inner diameter portion 29y of the nozzle body portion 24 y. As described in detail above, since the cement slurry flowing through the substantially central portion of the rear end inner diameter portion 28y of the nozzle body portion 24y collides with the substantially central portion of the flow path dividing portion 31y, the cement slurry flowing through the substantially central portion of the rear end inner diameter portion 28y after the collision flows into each space divided by the flow path dividing portion 31y, and is transported toward the inner circumferential surface of the intermediate inner diameter portion formed by reducing the diameter while increasing the velocity, the thickness of the boundary layer of the turbulent flow generated in the inner circumferential surface of the intermediate inner diameter portion can be reduced, and the formation can be fluidized more finely. Further, since the total cross-sectional area of the flow paths divided by the flow path dividing section 31y is 54.1% of the cross-sectional area of the hollow shape of the rear end inner diameter section 28y in the vicinity of the flow path dividing section 31y, the cement slurry flowing through the rear end inner diameter section 28y of the nozzle body 24y is divided into the spaces divided by the flow path dividing section 31y and is transported in the front end direction while being compressed by an appropriate compression force, and therefore, the fine ground can be fluidized while further increasing the speed of the cement slurry flowing through the rear end inner diameter section 28y of the nozzle body 24y, and the cutting ability of the cement slurry injected from the material liquid injection nozzle 21y at the front end of the nozzle body 24y is increased, whereby the structure of the ground can be broken and the cement slurry can be injected to a further distance. This is also the case where the total cross-sectional area of the flow paths divided by the flow path dividing section 31y occupies 40% to 60% of the cross-sectional area of the hollow shape in the vicinity of the flow path dividing section 31 y. Accordingly, the cutting ability of the cement paste ejected from the tip of the nozzle body 24y is further increased, whereby the structure of the ground can be destroyed, and the cement paste can be ejected over a longer distance. Here, the following modification is also applied to embodiment 3.

It should be understood that the embodiments disclosed herein are illustrative and not restrictive in all respects. The scope of the present invention is shown not by the above description but by the scope of the claims, and is intended to include meanings equivalent to the scope of the claims and all modifications within the scope.

The following describes modifications of the present invention.

(modification 1)

The modification 1 of the present invention is different from the modification 1 in that in the modification 1, the nozzle body mounting hole 23 of the leading end effector 3 is formed in a direction perpendicular to the axis of the leading end effector 3, and the nozzle body 24 is mounted in the nozzle body mounting hole 23, whereas in the modification 1, the nozzle body mounting hole 23a (including the air cap mounting hole 43a) of the leading end effector 3 is formed so as to face downward 30 degrees, and the nozzle body 24 is mounted in the nozzle body mounting hole 23a (see fig. 20). Here, fig. 20 is a view showing a nozzle body attached to a downward nozzle body attachment hole in modification 1 of the present invention. The following description will be specifically made.

Since the nozzle of the tip causing device 3 is usually provided at a position slightly above the tip of the tip causing device 3, when a structure is present in front of the tip of the device 3 due to the tip inserted into the ground, the cement paste (curing material liquid) cannot be injected near the structure, but as described above, by attaching the nozzle body 24 to the nozzle body attachment hole 23a (including the air cap attachment hole) formed so as to face downward by 30 degrees, even when a structure is present in front of the tip causing device 3 inserted into the ground and the tip causing device 3 cannot be inserted below the structure, the cement paste (curing material liquid) can be injected near the structure from the tip inner diameter portion of the nozzle body 24, and a cured body that is in close contact with the structure can be produced. In addition, in modification 1, the nozzle body mounting hole 23a is formed to be 30 degrees downward, but the present invention is not limited thereto, and may be formed to be 45 degrees downward or may be formed to have another downward angle. In modification 1, the tip nozzle 4 is not attached to the tip of the tip forming device 3, but a nozzle body attachment hole may be formed in the tip of the tip forming device, and the high-pressure jet nozzle device 1 such as the nozzle body 24 may be attached to the nozzle body attachment hole.

(modification 2)

The modification 2 of the present invention differs from the modification 1 in that in the modification 1, the nozzle body mounting hole 23 of the leading end effector 3 is formed in a direction perpendicular to the axis of the leading end effector 3, and the nozzle body 24 is mounted in the nozzle body mounting hole 23, whereas in the modification 2, the nozzle body mounting hole 23b (including the air cap mounting hole 43b) of the leading end effector 3 is formed upward, and the nozzle body 24 is mounted in the nozzle body mounting hole 23b (see fig. 21). Fig. 21 is a view showing a nozzle body attached to an upward nozzle body attachment hole in modification 2 of the present invention.

In the case where high-pressure air is injected from the air injection nozzle 22 of the leading end causing device 3, the injected high-pressure air can rise to the upper portion in the ground and form an air layer in the ground. As described above, by attaching the nozzle body 24 to the nozzle body attachment hole 23b formed upward and injecting the cement paste (curing material liquid) upward from the material liquid injection nozzle 21 at the tip of the nozzle body 24, the cement paste (curing material liquid) can be injected over a longer distance using the air layer.

(modification 3)

Modification 3 of the present invention is different from embodiment 1 in that, in embodiment 1, the flow path dividing portion 31 that divides the hollow shape of the rear end inner diameter portion 28 of the nozzle body portion 24 into a plurality of spaces is formed in a cross shape having a side width of 1.5mm, a length of 5.5mm, and a depth of 5.0mm, whereas modification 3 is a circular shape (4) having a hollow shape of a rear end inner diameter portion with a cross-sectional diameter of 10.0mm, a diameter of 3.2mm, and a depth of 5.0mm (see fig. 22 (a)). By forming the flow path dividing portion 31a outside the circular shape in this manner, the width of the flow path dividing portion 31a outside the circular shape can be increased, and the strength of the flow path dividing portion 31a can be increased. The channel dividing section 31v may be formed in the shape shown in fig. 22(b) to 22 (g). Fig. 22 is a view showing a flow path dividing portion formed in the rear end inner diameter portion in the extension portion of the nozzle body according to modification 3 of the present invention. In thatThe total cross-sectional area (32.2 mm) of the flow path divided by the flow path dividing section 31a²) A hollow cross-sectional area (78.5 mm) in the vicinity of the flow path dividing part 31a²) 41.0% of.

(modification 4)

Variation 4 of the present invention differs from embodiment 1 in that in embodiment 1, two air ejection nozzles 22 are provided and communicate with two air flow paths 10 corresponding to the respective air ejection nozzles 22, whereas variation 4 provides 6 air ejection nozzles 22 and two air flow paths 10(10a and 10b, 10b and 10c, 10c and 10d, 10d and 10e, 10e and 10f, 10f and 10a) corresponding to the respective air ejection nozzles 22 communicate. That is, the air flow path 10 of the leading end forming device 3 may be the air flow path 10 between the air jetting nozzles 22 disposed adjacent to each other at equal intervals in a common circumferential shape (see fig. 23). In this way, by sharing the adjacent air flow paths 10, the number of air flow paths in the tip end forming device 3 can be reduced, and a plurality of air injection nozzles 22 injecting in multiple directions can be attached to the tip end forming device 3 (see fig. 23). Here, fig. 23(a) is a view showing the mounting position of the high-pressure ejection nozzle device according to modification 4 of the present invention, and fig. 23(b) is a cross-sectional view showing the mounting position of the tip of the high-pressure ejection nozzle device according to modification 4 of the present invention.

(modification 5)

Modification 5 of the present invention differs from embodiment 1 in that in embodiment 1, two (a plurality of) nozzle body mounting holes 23 are formed at positions where the axial heights of the device 3 are different at the tip, and the nozzle bodies 24 are mounted to the respective nozzle body mounting holes 23, whereas modification 5 blocks the nozzle body mounting holes 23 with the flow path closing tool 40, and thus does not allow the cement paste and the compressed air to be ejected (see fig. 24). Here, fig. 24 is a view showing a flow path closing material attached to the nozzle body attachment hole 23 of modification 5 of the present invention.

The flow path closing material 40 is composed of a nozzle body mounting hole closing material 41 and an air flow path closing material 42 (see fig. 24). The nozzle body mounting hole closing member 41 has a hexagonal outer peripheral surface at the distal end thereof and has a male screw formed on the rear outer peripheral surface thereof. The air flow path closing tool 42 has a tip portion slightly protruding outward in the circumferential direction and a male screw formed on the rear outer circumferential surface thereof. Then, the nozzle body mounting hole closing tool 41 is mounted to the distal end effector 3 by screwing the male screw formed on the outer periphery of the nozzle body mounting hole closing tool 41 into the female screw formed on the inner periphery of the distal end of the nozzle body mounting hole 23 of the distal end effector 3. This can close the flow path of the cement slurry from the cement slurry-cum-water flow path 9. Further, the air flow path closing tool 42 can be attached to the distal end forming device 3 by screwing the male screw formed on the outer periphery of the air flow path closing tool 42 into the female screw formed on the inner periphery of the air cover attaching hole 43 of the distal end forming device 3. This can close the flow path of the air from the air flow path 10.

As described above, by attaching the flow path closing tool 40 to the flow path of the unused cement paste and compressed air, the attachment position of the nozzle body 24 suitable for the use as a cured body can be selected.

(modification 6)

Modification 6 of the present invention is different from embodiment 1 in that, in embodiment 1, the nozzle body 24 is constituted by a nozzle body 26 and a nozzle body extension 27 that can be screwed to the nozzle body (26), whereas modification 6 is constituted by a nozzle body 24w of a high-pressure injection nozzle device 1w constituted by a nozzle body 26w and a nozzle body extension 27w that is completely separated from and cannot be coupled to the nozzle body 26 w. Here, fig. 25(a) is an enlarged view of a portion P-P in fig. 3 according to modification 6 of the present invention. Fig. 25(b) is a view showing a nozzle body mounting hole of the tip forming device, fig. 26 is a view showing a component of a high-pressure jet nozzle device according to modification 6 of the present invention, and fig. 27 is a sectional view of the component. The nozzle body 24w will be specifically described below.

The nozzle body 26w has a cylindrical shape with a smaller diameter at a front portion thereof and a cylindrical shape with a slightly larger diameter at a rear portion thereof. Further, an O-ring mounting recess 47 is formed in the rear end surface of the nozzle body 26w (see fig. 27 b). The nozzle body extension 27w has a cylindrical shape with an increased diameter at its front portion and a cylindrical shape with a smaller diameter at its rear portion. In modification 6, as in embodiment 1, the nozzle body 26w and the nozzle body extension portion 27w are both formed of a high-strength material such as cemented carbide.

The hollow interior of the nozzle body 24w is formed by a rear end inner diameter portion 28w, an intermediate inner diameter portion 29w, and a front end inner diameter portion 30w (see fig. 27). The intermediate inner diameter portion 29w and the tip inner diameter portion 30w are formed in the nozzle body 26w, and the rear end inner diameter portion 28w is formed in the nozzle body extension 27 w. In modification 6, the rear end inner diameter portion 28w is formed to have a length of 9mm, the intermediate inner diameter portion 29w is formed to have a length of 15mm, and the front end inner diameter portion 30w is formed to have a length L of 8mm, as in embodiment 1 (see fig. 7). The intermediate inner diameter portion 29w is formed in a conical surface shape in which the inner peripheral surface is reduced in diameter in the distal direction at a throttle angle β of 12 to 20 degrees (preferably 12 to 15 degrees, more preferably 12 to 13 degrees), the distal end inner diameter portion 30w communicates with the distal end of the intermediate inner diameter portion 29w, the diameter d of the hollow interior is substantially the same as the diameter of the distal end of the intermediate inner diameter portion 29w, the length L is 2 to 4 times (preferably 3 to 4 times) the diameter d of the distal end of the intermediate inner diameter portion 29w, and the diameter d of the distal end inner diameter portion 30w is 2 mm. The rear end inner diameter portion 28w communicates with the rear end of the intermediate inner diameter portion 29w, and the diameter inside the communicating portion is formed to be substantially the same as the diameter of the rear end of the intermediate inner diameter portion 29 w. When the nozzle body 24w is attached to the distal end forming device 3, the inside of the cement slurry/water flow path 9 (curing material liquid flow path) in the distal end forming device 3 is protruded by 7 mm. Here, as in embodiment 1, the length of the nozzle body 24w that protrudes into the grout/water passage 9 (curing material liquid passage) in the device 3 toward the tip is half (D/2) of the diameter (D) of the grout/water passage 9 (curing material liquid passage) in the device 3 toward the tip. In modification 6, the total length LL (32mm) of the nozzle body 24w is 16 times the diameter d (2mm) of the tip end of the intermediate inner diameter portion 29w, as in embodiment 1, but the present invention is not limited thereto, and the total length LL of the nozzle body 24w may be 15 to 20 times the diameter of the tip end of the intermediate inner diameter portion 29w, or the total length LL of the nozzle body 24w may be 10 to 20 times the diameter d of the tip end of the intermediate inner diameter portion 29w, in a case where the total length LL of the nozzle body 24w cannot be increased. Further, a flow path dividing portion 31w that divides the hollow rear end inner diameter portion 28w into a plurality of spaces in cross section is formed in the rear end inner diameter portion 28w inside the nozzle body extension portion 27 w. The flow path dividing portion 31w is formed in a cross shape having a width of 1.5mm and a length of 5.5mm, as in embodiment 1. The flow path dividing section 31w may be modified to the shape of modification 3.

Next, a method of attaching the nozzle body 24w to the nozzle body attachment hole 23w formed in the side surface of the device upper tube 35 having the distal end, which is different from the method of attaching the nozzle body 24 according to embodiment 1, will be described. Here, a nozzle body extension fixing projection 38 is formed in the nozzle body mounting hole 23w formed in the side surface of the device upper pipe 35 at the tip end of the modification 6 (see fig. 25 b).

(1) First, the nozzle body extension 27w is inserted into the nozzle body attachment hole 23 w. Thus, the cylindrical shape formed at the tip of the nozzle body extension 27w comes into contact with the nozzle body extension fixing projection 38, and the nozzle body extension 27w is supported by the nozzle body extension fixing projection 38.

(2) Next, the nozzle body 26w is inserted into the nozzle body mounting hole 23 w. Thereby, the rear end of the nozzle body 26w is in contact with the front end side of the nozzle body extension 27w, but is sealed by the O-ring 46 inserted into the O-ring mounting recess 47 at the rear end of the nozzle body 26 w.

(3) Next, in the same order as the mounting order of embodiment 1, the nozzle body holder 32 and the like are fitted from the distal end direction of the nozzle body 26w, and the high-pressure injection nozzle device 1 including the nozzle body 24w is mounted in the nozzle body mounting hole 23 w. The nozzle body extension 27w attached in this manner is attached to the substantially central portion of the cement slurry/water flow path 9 (curing material liquid flow path) in the device 3 with its tip end protruding, as in embodiment 1. Further, in modification 6, similarly to embodiment 1, the protrusion may be made at least approximately 1/3 of the cross section of the grout/water passage 9 in the distal end forming device 3, and when the plurality of nozzle body mounting holes 23w are formed at positions having different heights in the axial direction of the distal end forming device 3 as in embodiment 1, the protrusion may be made at least approximately 1/2 to approximately 2/3 (preferably approximately 2/3) of the cross section of the grout/water passage 9 in the distal end forming device 3.

(modification 7)

Modification 7 of the present invention is different from embodiment 1 (including modifications 1 to 6) in that in embodiment 1, the rear end inner diameter portion 28 of the nozzle main body portion 24 communicates with the rear end of the intermediate inner diameter portion 29 and is formed to have a diameter substantially equal to the diameter of the rear end of the intermediate inner diameter portion 29, whereas in modification 7, the rear end inner diameter portion 28 of the nozzle main body portion 24 communicates with the rear end of the intermediate inner diameter portion 29, the communicating portion between the rear end inner diameter portion 28 and the intermediate inner diameter portion 29 has a diameter substantially equal to the diameter of the rear end of the intermediate inner diameter portion 29, and the diameter increases from the communicating portion between the rear end inner diameter portion 28 and the intermediate inner diameter portion 29 toward the rear end of the rear end inner diameter portion 28. In this case, the diameter may be increased toward the rear end of the rear end inner diameter portion 28 so as to be 12 degrees to 20 degrees (preferably 12 degrees to 15 degrees, more preferably 12 degrees to 13 degrees) which is the same angle as that of the intermediate inner diameter portion or so as to be 13 degrees or more or 18 degrees or more which is an angle larger than that of the intermediate inner diameter portion.

The diameter increases from the communicating portion between the rear end inner diameter portion 28 and the intermediate inner diameter portion 29 toward the rear end of the rear end inner diameter portion 28, so that more cement paste layers are fluidized and enter the nozzle body 24, and the cement paste can be ejected at a longer distance without reducing the cutting ability from the material liquid ejection nozzle 21 formed at the front end of the nozzle body 24.

(modification 8)

Modification 8 of the present invention is a modification in which modification 7 described above is applied to the shape of embodiment 3, and modification 8 differs from embodiment 3 in that in embodiment 3, the rear end inner diameter portion 28y of the nozzle main body portion 24y communicates with the rear end of the intermediate inner diameter portion 29y, and is formed so that the diameter thereof is substantially the same as the diameter of the rear end of the intermediate inner diameter portion 29y, whereas in modification 8, the rear end inner diameter portion 28z of the nozzle main body portion 24z communicates with the rear end of the intermediate inner diameter portion 29z, and the communicating portion between the rear end inner diameter portion 28z and the intermediate inner diameter portion 29z has a diameter substantially the same as the diameter of the rear end of the intermediate inner diameter portion 29z, and the diameter thereof is enlarged from the communicating portion between the rear end inner diameter portion 28z and the intermediate inner diameter portion 29z toward the rear end of the rear end inner diameter portion 28z (see fig. 28 to 31). In this case, the diameter may be increased toward the rear end of the rear end inner diameter portion 28z so as to be equal to the angle of the intermediate inner diameter portion 29z, that is, 12 to 20 degrees (preferably 12 to 13 degrees) or more, that is, 13 degrees or more, or 18 degrees or more. Here, fig. 28(a) is an enlarged view of a portion P-P in fig. 3 of a high-pressure spray nozzle device according to a modification 8 of the present invention, fig. 28(b) is a view showing a nozzle body mounting hole of a tip forming device, fig. 29 is a view showing components of the high-pressure spray nozzle device, fig. 30 is a cross-sectional view showing the components, and fig. 31 is a view showing a method of mounting the high-pressure spray nozzle device.

As described above, by increasing the diameter from the communicating portion between the rear end inner diameter portion 28z and the intermediate inner diameter portion 29z toward the rear end of the rear end inner diameter portion 28z, more cement slurry can be introduced into the nozzle body 24z in a fluidized manner, the fluidized cement slurry exerts a stronger jetting force at the front portion where the diameter is reduced, the cement slurry can be jetted so as not to attenuate the cutting ability from the material liquid jetting nozzle 21z formed at the front end of the nozzle body 24z, and the cement slurry can be jetted to a longer distance.

(modification 9)

In the above embodiment, "the total cross-sectional area of the flow paths divided by the flow path dividing section 31(31x, 31y) may be 40% to 60% of the cross-sectional area of the hollow shape in the vicinity of the flow path dividing section 31(31x, 31 y). "but not limited thereto, the total area of the cross-sections of the flow paths divided by the flow path dividing section 31(31x, 31y) may be 50% to 60% of the cross-sectional area of the hollow shape in the vicinity of the flow path dividing section 31(31x, 31 y). In particular, it was confirmed that this effect is large when the injection pressure from the high-pressure injection nozzle device 1(1x, 1y) is set to 20MPa or more.

Description of the reference numerals

1 high pressure spray nozzle device

1w high-pressure spray nozzle device

1x high pressure jet nozzle device

1y high-pressure jet nozzle device

2 injection rod

3 front end generating device

3x front end creation device

3y front end creation device

4 front end nozzle

5 operating machine

6 rotating ring

7 grout and water supply passage

8 air supply passage

9-cement-slurry dual-purpose water flow path

10 air flow path

11 supply source of water

12 air supply source

13 supply source of cement paste

14 water supply hose

15 air supply hose

16 grout supply hose

17 injection rod outer tube

17a leading end causes the outer tube of the device

18 injection rod inner tube

18a leading end causes the inner tube of the device

19 connecting pin insertion hole

20a binding pin injection rod recess

20b engaging the front end of the pin to create a device recess

21 liquid material spray nozzle

22 air injection nozzle

23 nozzle body part mounting hole

23a nozzle body mounting hole

23b nozzle body mounting hole

23w nozzle body part mounting hole

23x nozzle body mounting hole

23y nozzle body part mounting hole

24 nozzle body

24w nozzle body

24x nozzle body

24y nozzle body

25 air hood

25x air hood

25y air hood

26 nozzle body

26w nozzle body

26y nozzle body

27 nozzle body extension

27w nozzle body extension

27y nozzle body extension

27z nozzle body extension

28 rear end inner diameter part

28w rear end inner diameter part

28x rear end inner diameter part

28y rear end inner diameter part

28z rear end inner diameter part

29 intermediate inner diameter part

29w middle inner diameter part

29x intermediate inner diameter part

29y middle inner diameter part

30 front end inner diameter part

30w front end inner diameter part

30x front end inner diameter part

30y front end inner diameter part

31 flow path dividing part

31a flow path dividing part

31w channel dividing section

31x flow path dividing part

31y flow path dividing part

31z flow path dividing part

32 nozzle body support

32x nozzle body support

32y nozzle body support

33 cut out part

34 pressure difference valve

35 front end cause device upper pipe

36 combination pin

37 injection rod inner tube connecting pipe

38 nozzle body extension anchor tab

38x nozzle body extension fixation boss

38y nozzle body extension fixing projection

39 front end causes the device lower tube

40 flow path closing member

41 nozzle body mounting hole closing member

42 air flow path closing member

43 air hood mounting hole

43a air hood mounting hole

43b air hood mounting hole

44 injection stem protrusion

45 leading end causes a protrusion in the upper tube of the device

46O-ring

46x O shaped ring

46y O shaped ring

47O-ring mounting recess

47x O Ring mounting recess

47y O Ring mounting recess

48x nozzle body rear part.

Claims (7)

1. A high-pressure injection nozzle device which communicates with an axial solidified material liquid supply pipe formed in an injection rod and is provided on a side surface of a tip forming device connected to a tip of the injection rod,

a nozzle body part formed in a hollow shape, the nozzle body part including a conical intermediate inner diameter part formed by reducing the diameter of the inner peripheral surface in the direction of the front end; a front end inner diameter portion communicating with a front end of the intermediate inner diameter portion, the diameter of the front end inner diameter portion being the same as that of the front end of the intermediate inner diameter portion; a rear end inner diameter portion which communicates with a rear end of the intermediate inner diameter portion, is formed to have a diameter equal to or larger than a diameter of a rear end of the intermediate inner diameter portion in a rear end direction, is formed with a flow path dividing portion which divides a hollow shape into a plurality of spaces in a rear end inner diameter portion of the nozzle body portion, and has an overall length 4 to 20 times as large as a diameter of a front end of the intermediate inner diameter portion,

the flow path dividing section has the following portions: a central portion of the rear end inner diameter portion of the hollow shape near the flow path dividing portion has a portion corresponding to 2% to 20% of the area of the hollow shape cross-sectional area of the rear end inner diameter portion near the flow path dividing portion, and the solidified material liquid flowing in the central portion of the rear end inner diameter portion of the nozzle body portion collides with the central portion of the flow path dividing portion, so that the solidified material liquid colliding with the central portion of the rear end inner diameter portion is divided by the flow path dividing portion and flows into the respective flow paths, and is transported toward the inner peripheral surface of the intermediate inner diameter portion formed by reducing the diameter while increasing the velocity, whereby the boundary layer of turbulence generated in the inner peripheral surface of the intermediate inner diameter portion is reduced,

the cutting ability of the solidified material liquid ejected from the front end inner diameter portion of the nozzle main body portion is increased, and the solidified material liquid can be ejected at a longer distance.

2. The high-pressure spray nozzle device according to claim 1, wherein the total cross-sectional area of the flow paths divided by the flow path dividing portion is 40% to 60% of the cross-sectional area of the hollow shape of the rear end inner diameter portion in the vicinity of the flow path dividing portion.

3. The high-pressure injection nozzle device according to claim 1 or 2, wherein the hollow-shaped cross-sectional area in the vicinity of the flow path dividing portion is a hollow-shaped cross-sectional area immediately upstream of the flow path dividing portion.

4. The high-pressure injection nozzle device according to claim 1 or 2, wherein the hollow cross-sectional area in the vicinity of the flow path dividing portion is a hollow cross-sectional area immediately downstream of the flow path dividing portion.

5. The high-pressure injection nozzle device according to claim 1 or 2, wherein the flow path dividing portion is formed in a cross shape.

6. The high-pressure spray nozzle device according to claim 1 or 2, wherein the rear end inner diameter portion of the nozzle main body is provided so as to protrude into an axial solidified material liquid flow path formed in the front end generating device.

7. A foundation improvement device characterized by having a front end causing device equipped with a high pressure jetting nozzle device as claimed in any one of claims 1 to 6.

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