High-pressure injection nozzle device and ground improvement device equipped therewith

Abstract

To solve problems of a conventional high-pressure injection nozzle device including the necessity of much manufacturing cost due to the use of an air cover with a plurality of inclined grooves formed on an inner peripheral surface thereof, and the necessity of replacement of the air cover every time the air cover is damaged by an injected and splashed curing liquid (including crushed solid material and foundation).SOLUTION: A high-pressure injection nozzle device can suppress a manufacturing cost and a repair and replacement cost lower as the device has protrusions 50b that are disposed on an inner peripheral surface of an outer peripheral inclined groove member 50 having inclined grooves 50a inclined obliquely in substantially the same direction toward a tip direction on an inner peripheral surface, protrude inward, and are abutted against an outer peripheral surface of a nozzle body part 24. Compressed air can be injected from a compressed air injection port on a tip of an air flow channel between the inner peripheral surface of the outer peripheral inclined groove member 50 and the outer peripheral surface of the nozzle body part 24 in a state where the outer peripheral inclined groove member 50 rotating in circumferential direction of the outer peripheral surface of the nozzle body 24 is hard to fluctuate.SELECTED DRAWING: Figure 21

Description

[[TECHNICAL FIELD]]

[0001] The present invention relates to a high-pressure injection nozzle device provided on a side surface of a monitor that communicates with the inside of a hardening material liquid supply pipe in an injection rod and is connected to a tip end of the injection rod, and a ground improvement device including the same. [[BACKGROUND ART]]

[0002] Conventionally, there has been known a high-pressure injection nozzle device provided on a side surface of a monitor that communicates with the inside of a hardening material liquid supply pipe in an injection rod and is connected to a tip end of the injection rod, and a ground improvement device including the same.

[0003] In this type of high-pressure injection nozzle device 100, a material liquid injection nozzle 121 is provided inside the high-pressure injection nozzle device 100, and an air injection nozzle 122 is formed outside the material liquid injection nozzle 121 (see FIG. 26). The air injection nozzle 122 is formed between an outer peripheral surface of a nozzle body 126 and an inner peripheral surface of an air cover 125, and the inner peripheral surface of the air cover 125 is provided with a plurality of inclined grooves 125a of substantially the same shape that are inclined obliquely in substantially the same direction toward the tip end (see FIG. 27). When the hardening material liquid is injected from the material liquid injection nozzle 121 inside the high-pressure injection nozzle device 100 and compressed air is injected at high pressure from the air injection nozzle 122 outside the material liquid injection nozzle 121, the hardening material liquid is injected from the inside of the high-pressure injection nozzle device 100, and compressed air is injected at high speed from the outer side (outer peripheral portion) thereof, and the injected compressed air swirls along the inclined grooves 125a on the inner peripheral surface of the air cover 125. As a result, a swirling flow of compressed air is formed around the jet flow of the hardening material liquid injected from the material liquid injection nozzle 121, and the swirling flow of compressed air covers the periphery of the jet flow of the hardening material liquid as an air layer coating. Compared with the case where there is no air layer coating of compressed air, the cutting ability of the hardening material liquid injected from the inside of the high-pressure injection nozzle device 100 is increased, and the hardening material liquid can be injected to a longer distance (for example, Patent Document 1). Here, FIG. 26 is a longitudinal sectional view of a monitor equipped with a conventional high-pressure injection nozzle device, and FIG. 27 is a diagram showing constituent components of the same high-pressure injection nozzle device. [[PRIOR ART DOCUMENTS]] [Patent Documents]

[0004] [Patent Document 1] Patent No. 6754914 [Overview of the project] [Problems that the invention aims to solve]

[0005] However, conventional high-pressure injection nozzle devices use an air cover with multiple inclined grooves of approximately the same shape formed on its inner surface, sloping diagonally in roughly the same direction toward the tip. This poses a problem in that manufacturing an air cover with inclined grooves on its inner surface requires a complex process, resulting in high manufacturing costs. Furthermore, since the surface of the air cover is exposed to the outer surface of the high-pressure injection nozzle device, if the hardening agent liquid sprayed from the high-pressure injection nozzle device collides with solidified material such as rock, the hardening agent liquid (including crushed solids and ground) bounces back from the solidified material, damaging the air cover. This necessitates the replacement of the air cover, resulting in the problem of high manufacturing costs being incurred each time the air cover is replaced.

[0006] The present invention has been made in view of the above problems, and aims to provide a high-pressure injection nozzle device and a ground improvement device equipped therewith that can sufficiently increase the spraying distance of the hardening agent liquid sprayed from the high-pressure injection nozzle device, and that can prevent the manufacturing cost and repair / replacement cost of the high-pressure injection nozzle device from becoming excessively high. [Means for solving the problem]

[0007] To solve the above problems and achieve the above objective, the first aspect of the present invention relates to a high-pressure injection nozzle device provided on the side of a monitor connected to the tip of an injection rod, which communicates with a hardening agent liquid supply pipe formed in the axial direction within the injection rod, and comprises an intermediate inner diameter portion having a tapered surface shape formed by the inner circumferential surface decreasing in diameter towards the tip, a tip inner diameter portion communicating with the tip of the intermediate inner diameter portion and having a diameter approximately the same as the diameter of the tip of the intermediate inner diameter portion, and a rear end inner diameter portion communicating with the rear end of the intermediate inner diameter portion and having a diameter approximately the same as the diameter of the rear end of the intermediate inner diameter portion, or a diameter that expands from approximately the same diameter towards the rear end. The nozzle has a nozzle body with a hollow curing agent liquid channel, a hollow outer circumferential groove member fitted to the tip of the nozzle body, the outer circumferential surface of which is tapered toward the tip, and which has multiple inclined grooves formed on the outer circumferential surface that are obliquely inclined in substantially the same direction toward the tip, and an air channel formed between the inner circumferential surface and the outer circumferential surface of the nozzle body, a projection provided on the inner circumferential surface of the outer circumferential groove member that protrudes inward and abuts against the outer circumferential surface of the nozzle body, and an air cover in which a compressed air channel is formed between the inner circumferential surface and the outer circumferential surface of the outer circumferential groove member, the projection on the inner circumferential surface of the outer circumferential groove member is the nozzle body Department By being in contact with the outer surface of the nozzle body, Department As the outer circumferential inclined groove member rotates in the circumferential direction of the outer surface, and the outer surface of the nozzle body, compressed air is injected from the compressed air injection port at the tip of the air passage between the inner surface of the outer circumferential inclined groove member and the outer surface of the nozzle body, compressed air is injected from the tip between the inner surface of the air cover and the outer surface of the outer circumferential groove member as the outer circumferential groove member rotates, the area around the cement milk injection flow is covered by the compressed air injected from the compressed air injection port, and the outer circumferential inclined groove member is the nozzle body Department The air cover is characterized by being rotated at high speed around it, causing compressed air to swirl and be ejected more strongly from the tip between the inner surface of the air cover and the outer surface of the outer inclined groove member.

[0008] According to the present invention, a compressed air injection layer is formed from compressed air injected from the tip between the inner surface of the outer circumferential groove member and the outer surface of the nozzle body, and the compressed air injected from the tip between the inner surface of the "air cover" and the outer surface of the "outer circumferential groove member" can be swirled around the hardening agent liquid injected from the tip of the nozzle body via the compressed air injection layer. As a result, the compressed air injected from the tip between the inner surface of the air cover and the outer surface of the outer circumferential groove member is less likely to come into direct contact with the hardening agent liquid injected from the tip of the nozzle body, allowing the compressed air injected from the tip between the inner surface of the air cover and the outer surface of the outer circumferential groove member to swirl with a greater swirling force, and the hardening agent liquid injected from the tip of the nozzle body can be pressed more strongly towards the center by the swirling compressed air flow. Furthermore, an air passage is formed between the inner surface of the outer circumferential groove member and the outer surface of the nozzle body, and the inner surface of the outer circumferential groove member has a projection that protrudes inward and abuts against the outer surface of the nozzle body, so the projection on the inner surface of the outer circumferential groove member is the nozzle body Department By being in contact with the outer surface of the nozzle body, Department As the outer circumferential inclined groove member rotates in the circumferential direction of the outer surface, and the outer surface of the nozzle body, compressed air is injected from the compressed air injection port at the tip of the air passage between the inner surface of the outer circumferential inclined groove member and the outer surface of the nozzle body, compressed air is injected from the tip between the inner surface of the air cover and the outer surface of the outer circumferential groove member as the outer circumferential groove member rotates, the area around the cement milk injection flow is covered by the compressed air injected from the compressed air injection port, and the outer circumferential inclined groove member is the nozzle body Department By rotating at high speed around the nozzle, compressed air can be swirled and sprayed more strongly from the tip between the inner surface of the air cover and the outer surface of the outer inclined groove member. This extends the region (potential core region) in which the velocity of the hardening agent liquid sprayed from the tip of the nozzle body does not decrease, allowing the hardening agent liquid to be sprayed over a longer distance.

[0009] A second aspect of the present invention relates to a high-pressure injection nozzle device according to the first aspect, characterized in that the inclined grooves of the outer peripheral inclined groove member are formed on the outer peripheral surface of the outer peripheral inclined groove member in substantially the same shape and are provided in a range of 6 to 12.

[0010] According to the present invention, the inclined grooves of the outer peripheral inclined groove member are formed on the outer peripheral surface of the outer peripheral inclined groove member with substantially the same shape and are provided in a range of 6 to 12. As a result, compressed air flowing along the 6 to 12 inclined grooves is strongly ejected from the tip between the inner peripheral surface of the air cover and the outer peripheral surface of the outer peripheral inclined groove member in a large flow along the inclined grooves, and the ejected compressed air can be efficiently swirled together with the hardening agent liquid ejected from the tip of the nozzle body. This compressed air swirling around the hardening agent liquid efficiently and strongly presses the hardening agent liquid ejected from the tip of the nozzle body toward the center, and the ground around the outer edge of the swirling flow of compressed air swirling around the hardening agent liquid is efficiently cut while being pressed. This makes it possible to increase the thickness of the compressed air layer around the hardening agent liquid ejection flow, and the compressed air layer makes it difficult for the hardening agent liquid ejection flow immediately after ejection from the tip of the nozzle body to come into contact with the surrounding ground. This allows the region where the velocity of the hardening agent liquid sprayed from the tip of the nozzle body does not decrease (potential core region) to be maintained for a longer period, enabling the hardening agent liquid to be sprayed over a longer distance.

[0011] A third aspect of the present invention relates to a high-pressure injection nozzle device according to the first aspect, wherein the outer surface of the outer circumferential groove member has a curved outer surface portion provided on the outer circumferential surface of the outer circumferential groove member, which protrudes outward and abuts against the inner circumferential surface of the air cover, and the outer surface portion is formed in a curved shape, and because the curved outer surface portion is formed in a curved shape, the outer circumferential groove member is the nozzle body Department When the outer surface rotates in the circumferential direction, the contact area between the outer surface of the outer inclined groove member and the inner surface of the air cover decreases, and the resistance force between the rotating outer surface of the outer inclined groove member and the inner surface of the air cover decreases, so the outer inclined groove member moves to the nozzle body DepartmentThe outer surface can be rotated at high speed in the circumferential direction, and compressed air can be ejected more strongly while swirling from the tip between the inner surface of the air cover and the outer surface of the outer inclined groove member.

[0012] According to the present invention, since the curved outer peripheral surface portion is formed in a curved shape, the outer peripheral inclined groove member is the nozzle body Department When the outer surface rotates in the circumferential direction, the contact area between the outer surface of the outer inclined groove member and the inner surface of the air cover decreases, and the resistance force between the rotating outer surface of the outer inclined groove member and the inner surface of the air cover decreases, so the outer inclined groove member moves to the nozzle body Department The outer surface can be rotated at high speed in the circumferential direction, and compressed air can be ejected more strongly while swirling from the tip between the inner surface of the air cover and the outer surface of the outer inclined groove member.

[0013] A fourth aspect of the present invention relates to a high-pressure injection nozzle device according to the second aspect, characterized in that the inclined grooves of the outer peripheral inclined groove member are inclined obliquely on the outer peripheral surface of the outer peripheral inclined groove member in the direction toward the tip within a range of approximately 13.0 degrees to approximately 56.0 degrees.

[0014] According to the present invention, the inclined grooves of the outer peripheral inclined groove member are inclined diagonally on the outer peripheral surface of the outer peripheral inclined groove member within a range of approximately 13.0 degrees to approximately 56.0 degrees toward the tip. As a result, the hardening agent liquid sprayed from the tip of the nozzle body is efficiently and strongly pressed toward the center by the compressed air swirling around it, and the ground around the outer edge of the swirling flow is efficiently cut while being pressed by the swirling flow of compressed air swirling around the hardening agent liquid. This makes it possible to increase the thickness of the compressed air layer around the hardening agent liquid spray flow, and the compressed air layer makes it difficult for the hardening agent liquid spray flow immediately after being sprayed from the tip of the nozzle body to come into contact with the surrounding ground. This makes it possible to lengthen the region (potential core region) in which the velocity of the hardening agent liquid sprayed from the tip of the nozzle body does not decrease, and to spray the hardening agent liquid over a longer distance.

[0015] A fifth aspect of the present invention relates to a high-pressure injection nozzle device according to the first aspect, wherein a flow path division section is formed in the rear end inner diameter portion of the nozzle body portion, dividing the hollow cross-section into a plurality of spaces, and the total cross-sectional area of ​​the flow paths divided by the flow path division section is 40% to 60% of the cross-sectional area of ​​the hollow cross-section of the rear end inner diameter portion near the flow path division section.

[0016] According to the present invention, the total cross-sectional area of ​​the channels divided by the channel division section is 40% to 60% of the cross-sectional area of ​​the hollow cross-section of the inner diameter section at the rear end near the channel division section. As a result, the hardening agent liquid flowing through the inner diameter section at the rear end of the nozzle body is divided into the respective spaces divided by the channel division section and is compressed with an appropriate compressive force while being sent towards the tip. The hardening agent liquid sent towards the tip while being compressed increases in velocity in each space divided by the channel division section, which reduces the thickness of the turbulent boundary layer generated on the inner circumferential surface of the intermediate inner diameter section, allowing for finer laminar flow. This allows the hardening agent liquid sprayed from the tip of the nozzle body to be sprayed at approximately the same velocity across almost the entire surface of the nozzle opening, enabling the hardening agent liquid to be sprayed over longer distances and increasing the cutting ability of the hardening agent liquid sprayed from the tip of the nozzle body, thereby destroying the structural integrity of the ground.

[0017] According to the present invention, an air flow path is formed between the inner peripheral surface of the outer peripheral inclined groove member and the outer peripheral surface of the nozzle body, so a compressed air injection layer is formed by compressed air injected from the tip between the inner peripheral surface of the outer peripheral inclined groove member and the outer peripheral surface of the nozzle body. The compressed air injected from the tip between the inner peripheral surface of the "air cover" and the outer peripheral surface of the "outer peripheral inclined groove member" can be swirled around the hardening material liquid injected from the tip of the nozzle body via the compressed air injection layer. This makes it difficult for the compressed air injected from the tip between the inner peripheral surface of the air cover and the outer peripheral surface of the outer peripheral inclined groove member to directly contact the hardening material liquid injected from the tip of the nozzle body, allows the compressed air injected from the tip between the inner peripheral surface of the air cover and the outer peripheral surface of the outer peripheral inclined groove member to be swirled with greater swirling force, and enables the compressed air swirling flow to more strongly press the hardening material liquid injected from the tip of the nozzle body toward the center. As a result, the length of the region where the velocity of the hardening material liquid injected from the tip of the nozzle body does not decay (potential core region) can be increased, and the hardening material liquid can be injected to a longer distance.

[0018] A sixth aspect of the present invention provides a ground improvement device equipped with the high-pressure injection nozzle device according to any one of the first to fifth aspects mounted on a monitor. Effects of the Invention

[0019] According to the high-pressure injection nozzle device of the present invention, the injection reaching distance of the hardening material liquid injected from the high-pressure injection nozzle device can be sufficiently increased, and the manufacturing cost and repair / replacement cost of the high-pressure injection nozzle device can be prevented from becoming high. Brief Description of the Drawings

[0020] [Figure 1] It is a diagram showing the construction status of the ground improvement device to which the high-pressure injection nozzle device according to the first embodiment of the present invention is mounted. [Figure 2] It is an external perspective view of a monitor to which the high-pressure injection nozzle device is mounted. [Figure 3] It is a sectional view taken along line A-A of Figure 2. [Figure 4] Figure 3 is a cross-sectional view of BB. [Figure 5] This figure shows a method for assembling a high-pressure injection nozzle device and its peripheral equipment according to a first embodiment of the present invention. [Figure 6] (a) This is an enlarged view of the PP portion in Figure 3. (b) This is a diagram showing the mounting holes for the nozzle body of the monitor. [Figure 7] This is a cross-sectional view showing how to install the high-pressure injection nozzle device. [Figure 8] This figure shows the components of a high-pressure injection nozzle device according to the first embodiment of the present invention. [Figure 9] This is a cross-sectional view of the same component. [Figure 10] (a) A front perspective view of the outer circumferential inclined groove member of the high-pressure injection nozzle device in the first embodiment of the present invention. (b) A rear perspective view of the outer circumferential inclined groove member of the high-pressure injection nozzle device. (c) A rear view of the outer circumferential inclined groove member of the high-pressure injection nozzle device. (d) A side view of the outer circumferential inclined groove member of the high-pressure injection nozzle device. (e) A front view of the outer circumferential inclined groove member of the high-pressure injection nozzle device. (f) A cross-sectional view of Figure 10(c). [Figure 11] This figure shows the cross-sectional diameter of the inclined groove in the outer circumferential inclined groove member of the high-pressure injection nozzle device. [Figure 12] (a) A diagram showing a method for mounting the components of a high-pressure injection nozzle device according to the first embodiment of the present invention. (b) A rear view of the high-pressure injection nozzle device. (c) A side view of the high-pressure injection nozzle device. (d) A front view of the high-pressure injection nozzle device. [Figure 13] Figure 11 shows the cross-sectional views from AA to MM. [Figure 14](a) A front view of the outer circumferential inclined groove member of the high-pressure injection nozzle device in the first embodiment of the present invention. (b) A cross-sectional view of FF in Figure 14(a). (c) A diagram showing the diameter of the recess and the diameter of the protrusion of the inclined groove on the rear end surface of the outer circumferential inclined groove member of the high-pressure injection nozzle device in the first embodiment of the present invention. (d) A diagram showing the diameter of the recess and the diameter of the protrusion of the inclined groove on the front end surface of the outer circumferential inclined groove member of the high-pressure injection nozzle device. (e) A side perspective view of the outer circumferential inclined groove member of the high-pressure injection nozzle device. (f) A diagram showing a method for calculating the inclination angle of the outer circumferential inclined groove member of the high-pressure injection nozzle device. [Figure 15] Figure 3 is a cross-sectional view of CC. [Figure 16] This diagram shows the spray state from the nozzle of the high-pressure injection nozzle device. [Figure 17] (a) This figure shows the state in which the mud around the monitor is discharged to the ground. (b) This figure shows the state in which the mud around the high-pressure injection nozzle device is discharged to the ground. [Figure 18] This figure shows the "standard deviation of the impact load" of the water sprayed from the nozzle of the high-pressure injection nozzle device. [Figure 19] This figure shows the "average impact load" of the water sprayed from the nozzle of the high-pressure injection nozzle device. [Figure 20] (a) This is an external perspective view of a monitor equipped with a high-pressure injection nozzle device according to a second embodiment of the present invention. (b) This is a front view of the same high-pressure injection nozzle device. [Figure 21] This is a JJ cross-sectional view of Figure 20(b). [Figure 22] (a) A front view of the outer circumferential inclined groove member of the high-pressure injection nozzle device in the second embodiment of the present invention. (b) A cross-sectional view of KK in Figure 22(a). [Figure 23] This figure shows the injection state from the injection nozzle of the high-pressure injection nozzle device in the second embodiment of the present invention. [Figure 24](a) A front view of the outer circumferential inclined groove member of the high-pressure injection nozzle device in Modification 1 of the present invention. (b) A cross-sectional view of GG in Figure 24(a). (c) A diagram showing the diameter of the recess and the diameter of the protrusion of the inclined groove on the rear end surface of the outer circumferential inclined groove member of the high-pressure injection nozzle device in Modification 1 of the present invention. (d) A diagram showing the diameter of the recess and the diameter of the protrusion of the inclined groove on the front end surface of the outer circumferential inclined groove member of the high-pressure injection nozzle device. (e) A side perspective view of the outer circumferential inclined groove member of the high-pressure injection nozzle device. (f) A diagram showing the method for calculating the inclination angle of the outer circumferential inclined groove member of the high-pressure injection nozzle device. [Figure 25] (a) A front view of the outer circumferential inclined groove member of the high-pressure injection nozzle device in Modification 2 of the present invention. (b) A cross-sectional view of HH in Figure 25(a). (c) A diagram showing the diameter of the recess and the diameter of the protrusion of the inclined groove on the rear end surface of the outer circumferential inclined groove member of the high-pressure injection nozzle device in Modification 2 of the present invention. (d) A diagram showing the diameter of the recess and the diameter of the protrusion of the inclined groove on the front end surface of the outer circumferential inclined groove member of the high-pressure injection nozzle device. (e) A side perspective view of the outer circumferential inclined groove member of the high-pressure injection nozzle device. (f) A diagram showing the method for calculating the inclination angle of the outer circumferential inclined groove member of the high-pressure injection nozzle device. [Figure 26] This is a longitudinal cross-sectional view of a monitor equipped with a conventional high-pressure injection nozzle device. [Figure 27] This is a diagram showing the components of the high-pressure injection nozzle device. [Modes for carrying out the invention]

[0021] (First Embodiment) Hereinafter, a ground improvement device equipped with a high-pressure injection nozzle device according to the first embodiment of the present invention will be described with reference to the drawings. Here, Figure 1 is a diagram showing the construction status of the ground improvement device equipped with a high-pressure injection nozzle device according to the first embodiment of the present invention.

[0022] As shown in Figure 1, a monitor 3 is attached to the tip of the injection rod 2. Water (liquid) supplied through the injection rod 2 and monitor 3 is sprayed from a tip nozzle 4 provided at the tip of the monitor 3, and cement milk (hardening agent liquid) and air supplied through the injection rod 2 and monitor 3 are sprayed from a high-pressure spray nozzle device 1A provided on the side of the monitor 3.

[0023] The work machine 5 supports the injection rod 2 and is a machine that moves the injection rod 2 up and down, rotates, and swings. As a result, the injection rod 2 and monitor 3 can be moved not only up and down but also rotated and swung by the work machine 5.

[0024] The swivel 6 is attached to the rear end of the injection rod 2 and is connected to the water, air, and cement milk supply hoses 14, 15, and 16 supplied from the water supply source 11, air supply source 12, and cement milk (hardening agent liquid) supply source 13, respectively. It also supplies water, air, and cement milk to the air supply passage 8 and the cement milk / water supply passage 7 provided inside the injection rod 2 (see Figures 1 to 3). Here, Figure 2 is an external perspective view of a monitor equipped with the high-pressure injection nozzle device according to the first embodiment of the present invention, and Figure 3 is a cross-sectional view AA of Figure 2. In Figures 2 and 3, the upper side of the injection rod 2 is omitted.

[0025] Next, the configuration of the injection rod 2 and monitor 3 will be explained in detail using Figures 2 to 4. Here, Figure 4 is a cross-sectional view of BB in Figure 3.

[0026] The injection rod 2 is composed of a double pipe. Cement grout or water (liquid) is supplied to the inner cement grout / water supply channel 7 inside the injection rod 2, and air is supplied to the outer air supply channel 8 inside the injection rod 2 (see Figure 3). In the first embodiment, the cement grout (hardening agent liquid) supply pipe and the water supply pipe are configured as a single supply pipe using the cement grout / water supply channel 7. However, the invention is not limited to this, and the cement grout (hardening agent liquid) supply pipe and the water supply pipe may be configured as separate supply pipes. Furthermore, when the cement grout (hardening agent liquid) supply pipe and the water supply pipe are configured as separate supply pipes, a multi-layered pipe such as a triple pipe or a porous pipe may be used to separate the cement grout (hardening agent liquid) and water. Also, in the first embodiment, the inner part of the injection rod 2, which is composed of a double pipe, is the cement grout / water supply channel 7, and the outer part is the air supply channel 8. However, the invention is not limited to this, and the inner part of the injection rod 2, which is composed of a double pipe, may be the air supply channel, and the outer part may be the cement grout / water supply channel.

[0027] Furthermore, as described above, the injection rod 2 is attached in connection with the monitor 3. The connection between the injection rod 2 and the monitor 3 will be described later. Here, the injection rod 2 is a double-walled tube consisting of an injection rod inner tube 2a (hardening agent liquid supply tube) with an outer diameter of 33 mm and an inner diameter of 23 mm, and an injection rod outer tube 2b with an outer diameter of 73 mm and a circular cross-section with an inner diameter of 61 mm (see Figures 2 and 3). The lower part of the injection rod outer tube 2b has a connecting pin insertion port 19, and a connecting pin injection rod recess 20a is formed on the lower inner surface, which is approximately the same diameter as the half-outer circumference of the connecting pin 36 and communicates with the connecting pin insertion port 19 (see Figures 2, 3, and 5). The outer diameter of the injection rod inner tube 2a is reduced to 22 mm from slightly below the upper end of the lower part of the injection rod outer tube 2b (the position where the inner diameter is expanded). In the first embodiment, an injection rod outer tube 2b with a circular cross-section of approximately 73 mm in outer diameter was used. However, the invention is not limited to this, and an injection rod outer tube with a circular cross-section of approximately 50 mm to 140 mm in diameter (for example, approximately 73 mm) may be used. Furthermore, if an injection rod outer tube with a circular cross-section of approximately 50 mm to 140 mm in diameter (for example, approximately 73 mm) is used, the inner diameter of the injection rod inner tube 2a may be set to 14 mm to 30 mm. Here, the inner diameter of the injection rod inner tube 2a is determined by the flow rate of cement grout flowing through the injection rod inner tube 2a. In addition, an injection rod outer tube having a hexagonal cross-section may be used. Figure 5 shows the assembly method of the high-pressure injection nozzle device and its peripheral equipment in the first embodiment of the present invention.

[0028] As described above, Monitor 3 is attached to the tip of Injection Rod 2. Inside Monitor 3, a cement milk / water channel 9 is formed axially in the center, communicating with the cement milk / water supply channel 7 of Injection Rod 2. Four air channels 10 are formed axially on the outer circumference of the cement milk / water channel 9, communicating with the air supply channel 8 of Injection Rod 2 (see Figures 2 to 4). Details of the air channels 10 will be described later. In this way, water, air, and cement milk supplied from the water supply source 11, air supply source 12, and cement milk supply source 13, respectively, are injected from the nozzles 1, 4, etc., via the respective supply hoses 14, 15, 16 → swivel 6 → respective supply channels 7, 8 → respective channels 9, 10 (see Figures 1 and 3). Here, the water and cement milk supplied from the water supply source 11 and cement milk supply source 13, respectively, are supplied to the cement milk / water supply channel 7 via the swivel 6 from the respective supply hoses 14, 16 for water and cement milk. In the first embodiment, the cement milk (hardening agent liquid) channel and the water channel were configured as a single channel using the cement milk / water channel 9. However, the embodiment is not limited to this, and the cement milk (hardening agent liquid) channel and the water channel may be configured as separate channels.

[0029] Furthermore, Monitor 3 has a maximum outer diameter of 90 mm, and inside Monitor 3, a cement grout / water channel 9 with a diameter of 16 mm is formed in the center, and a double pipe is used which consists of a monitor inner pipe 3a with an outer diameter of 26 mm and an inner diameter of 16 mm and a monitor outer pipe 3b with an outer diameter of 90 mm and an inner diameter of 78 mm, and an air channel 10 is formed between the monitor inner pipe 3a and the monitor outer pipe 3b. Specifically, this air channel 10 consists of a channel between the monitor inner pipe 3a and the monitor outer pipe 3b that communicates with the air supply channel 8 of the injection rod 2, and four channels formed inside Monitor 3 that communicate with that channel (see Figures 3 and 4). In this way, the air channel 10 inside Monitor 3 is in communication with the air supply channel 8 inside the injection rod 2 because the channel between the monitor inner pipe 3a and the monitor outer pipe 3b that constitutes the air channel 10 is in communication with the air supply channel 8 inside the injection rod 2. As described above, a high-pressure injection nozzle device 1A for injecting cement grout and air is provided on the side of monitor 3, and a coupling pin monitor recess 20b with approximately the same diameter as the half-inner circumference of the coupling pin 36 is formed on the upper side of the monitor 3 (see Figure 5). This coupling pin monitor recess 20b is fitted with the coupling pin injection rod recess 20a of the injection rod 2 to form a coupling pin insertion hole 19a that communicates with the coupling pin insertion port 19, and the coupling pin 36 is inserted into the coupling pin insertion hole 19a. In addition, a tip nozzle 4 for injecting water (liquid) is provided at the tip of monitor 3.

[0030] A differential pressure valve 34 is provided at the bottom of the monitor 3 (see Figure 3). This differential pressure valve 34 is opened by low-pressure water supplied through the cement milk / water supply passage 7 and the cement milk / water flow path 9 in the monitor 3, and the low-pressure water supplied from the tip nozzle 4 is injected through the opened differential pressure valve 34. Then, the differential pressure valve 34 is closed by cement milk supplied through the cement milk / water supply passage 7 and the cement milk / water flow path 9 in the monitor 3, and cement milk is injected from the material liquid injection nozzle 21 (inside the tip of the high-pressure injection nozzle device 1A) as described later. Specifically, during drilling, low-pressure water is supplied through the cement milk / water supply passage 7 of the injection rod 2 and the cement milk / water flow path 9 in the monitor 3 which is in communication with the cement milk / water supply passage 7, and the low-pressure water supplied from the tip nozzle 4 is ejected through the open differential pressure valve 34. After drilling is complete, cement grout is supplied via the cement grout / water supply channel 7 of the injection rod 2 and the cement grout / water supply channel 9 in the monitor 3 which is in communication with the cement grout / water supply channel 7. When the differential pressure valve 34 is closed, the supplied cement grout is injected from the material liquid injection nozzle 21 (inside the tip of the high-pressure injection nozzle device 1A).

[0031] Next, the high-pressure injection nozzle device 1A will be described in detail using Figures 8 to 10. Here, Figure 8 is a diagram showing the components of the high-pressure injection nozzle device in the first embodiment of the present invention, Figure 9 is a cross-sectional view of the same components, Figure 10(a) is a front perspective view of the outer circumferential inclined groove member of the high-pressure injection nozzle device in the first embodiment of the present invention, Figure 10(b) is a rear perspective view of the outer circumferential inclined groove member of the high-pressure injection nozzle device, Figure 10(c) is a rear view of the outer circumferential inclined groove member of the high-pressure injection nozzle device, Figure 10(d) is a side view of the outer circumferential inclined groove member of the high-pressure injection nozzle device, Figure 10(e) is a front view of the outer circumferential inclined groove member of the high-pressure injection nozzle device, and Figure 10(f) is a DD cross-sectional view of Figure 10(c).

[0032] The high-pressure injection nozzle device 1A includes a nozzle body 24, an outer peripheral inclined groove member 32A, and an air cover 25 (see Figures 8 and 9).

[0033] The nozzle body portion 24 consists of a nozzle body 26 and a nozzle body extension portion 27 (see Figure 8). Specifically, the nozzle body 26 has a roughly cylindrical shape with a smaller diameter at the front and a roughly cylindrical shape with a slightly larger diameter at the rear. The hollow interior of the nozzle body portion 24 consists of a rear end inner diameter portion 28, an intermediate inner diameter portion 29, and a tip inner diameter portion 30 (see Figure 9). The intermediate inner diameter portion 29 and the tip inner diameter portion 30 are formed inside the nozzle body 26, and the rear end inner diameter portion 28 is formed inside the nozzle body extension portion 27. Thus, the hollow interior of the nozzle body 24 is composed of a tapered intermediate inner diameter section 29 formed by the inner circumferential surface narrowing towards the tip, a tip inner diameter section 30 communicating with the tip of the intermediate inner diameter section 29 and having a diameter approximately the same as the tip of the intermediate inner diameter section 29, and a rear end inner diameter section 28 communicating with the rear end of the intermediate inner diameter section 29 and having a diameter approximately the same as the rear end of the intermediate inner diameter section 29. As a result, the cement milk supplied via the cement milk / water supply pipe 7 in the injection rod 2 and the cement milk / water flow path 9 in the monitor 3 which communicates with the cement milk / water supply path 7 is sent into the nozzle body 24 in the order of nozzle body extension section 27 → nozzle body 26, and is then injected from the material liquid injection nozzle 21, as will be described later (see Figure 15). Furthermore, a flow path division section 31 is formed in the rear end inner diameter section 28 within the nozzle body extension section 27, dividing the hollow cross-section of the rear end inner diameter section 28 into multiple spaces. The outer diameter of the rear end inner diameter section 28 is reduced by the flow path division section 31, and the flow path division section 31 within the rear end inner diameter section 28 is formed such that the area of ​​the approximately central part occupies 2% to 20% of the cross-sectional area of ​​the front outer diameter of the rear end inner diameter section 28 (the cross-sectional area of ​​the reduced portion of the rear end inner diameter section 28) (see Figure 9). In the first embodiment, the diameter of the rear end inner diameter section 28 within the nozzle body extension section 27 is formed to be approximately the same as the diameter of the rear end of the intermediate inner diameter section 29, but it is not limited to this, and it may be formed to be approximately the same as the diameter of the rear end of the intermediate inner diameter section 29 and then expand toward the rear end. Here, Figure 15 is a cross-sectional view of CC in Figure 3.

[0034] The total cross-sectional area of ​​the channels divided by the channel division section 31 is 9.45 mm². 2) is the outer diameter cross-sectional area of ​​the rear end inner diameter portion 28 (outer diameter cross-sectional area of ​​the reduced diameter portion of the rear end inner diameter portion 28) (23.7 mm 2 It accounts for approximately 40% of the total area. In the first embodiment, it was explained that the total cross-sectional area of ​​the flow channels divided by the flow channel division section 31 accounts for approximately 40% of the leading outer diameter cross-sectional area of ​​the rear end inner diameter section 28. However, this is not limited to this, and the total cross-sectional area of ​​the flow channels divided by the flow channel division section 31 may account for 40% to 60% of the leading outer diameter cross-sectional area of ​​the rear end inner diameter section 28, or it may account for 40% to 60% of the rear outer diameter cross-sectional area of ​​the rear end inner diameter section 28 instead of the leading outer diameter cross-sectional area of ​​the rear end inner diameter section 28, or it may account for 40% to 60% of the hollow cross-sectional area of ​​the rear end inner diameter section 28 near the flow channel division section 31.

[0035] Furthermore, the nozzle body portion 24 is inserted into a nozzle body portion mounting hole 23 formed on the side of the monitor 3. Two of these nozzle body portion mounting holes 23 are formed at equal intervals on the circumference at different axial heights of the monitor 3. In this way, multiple nozzle body portion mounting holes 23 are formed at different axial heights of the monitor 3, so by attaching multiple nozzle body portions 24 to nozzle body portion mounting holes 23 at different heights according to the application, various shapes of solidified bodies can be efficiently created in the ground in a short time. In the first embodiment, two nozzle body portion mounting holes 23 were formed at equal intervals on the circumference at different axial heights of the monitor 3, but they do not have to be at different axial heights of the monitor 3, nor do they have to be formed at equal intervals on the circumference. Also, the number of nozzle body portion mounting holes 23 does not have to be two; there may be two or more (preferably four or more), such as three, four, or six, or one. Here, Figure 6(a) is an enlarged view of the PP portion in Figure 3, and Figure 6(b) shows the mounting hole for the nozzle body of the monitor.

[0036] The outer circumferential inclined groove member 32A is hollow and fitted to the tip of the nozzle body 24. Its outer circumferential surface tapers towards the tip, and eight inclined grooves 32a are formed on the outer circumferential surface, sloping diagonally to the left toward the tip (see Figures 8 and 10). Since the inclined grooves 32a are formed on the outer circumferential surface of the outer circumferential inclined groove member 32A in this way, complex processes are not required when manufacturing the inclined grooves 32a on the outer circumferential surface of the outer circumferential inclined groove member 32A, and the manufacturing cost of the high-pressure injection nozzle device 1A can be kept low. Furthermore, when the cement grout sprayed from the high-pressure injection nozzle device 1A collides with solidified material such as rock, the rebounded cement grout (including crushed solid material and ground) collides with the air cover 25, damaging the air cover 25 and requiring replacement. However, since the outer circumferential inclined groove member 32A, on which the inclined grooves 32a are formed, is a separate component from the air cover 25, only the inexpensive air cover 25 needs to be replaced, further reducing the repair and replacement cost of the high-pressure injection nozzle device 1A. In the first embodiment, the outer peripheral inclined groove member 32A has inclined grooves 32a formed on its outer peripheral surface that are inclined diagonally to the left toward the tip. However, it is not limited to this, and inclined grooves 32a formed on its outer peripheral surface that are inclined diagonally to the right toward the tip may also be formed. Furthermore, in the first embodiment, the outer peripheral inclined groove member 32A has eight inclined grooves 32a formed on its outer peripheral surface that are inclined diagonally to the left toward the tip. However, it is not limited to this, and multiple inclined grooves 32a, such as 6 to 12 (6 to 8 or 8 to 10), formed on its outer peripheral surface that are inclined diagonally to the left toward the tip may also be formed.

[0037] Furthermore, the outer circumferential inclined groove member 32A is formed with an outer circumferential surface that tapers towards the tip (see Figures 8 to 10), and the cross-sectional diameter decreases towards the tip (see Figure 11). Here, Figure 11 is a diagram showing the cross-sectional diameter of the inclined groove of the outer circumferential inclined groove member of the high-pressure injection nozzle device in the first embodiment of the present invention. In Figure 11, the diameter connecting the recesses (lowest part) and the convex parts (upper part) of the inclined groove 32a in each cross-section of the outer circumferential inclined groove member 32A is shown. Specifically, as shown in the upper part of Figure 11, the diameter of the recess of the inclined groove 32a on the outer circumference of the outer circumference inclined groove member 32A (see upper values ​​in Figure 11) in each cross-section (A to M sections) of the outer circumference inclined groove member 32A is "Φ16.84mm (A section)"..."Φ14.47mm (K section)" "Φ14.24mm (L section)"..."Φ14.0mm (M section)", with the cross-sectional diameter decreasing towards the tip. Similarly, as shown in the lower part of Figure 11, the diameter of the protrusion of the inclined groove 32a on the outer circumference of the outer circumference inclined groove member 32A in each cross-section (A to M sections) of the outer circumference inclined groove member 32A is "Φ28.0mm (A section)"..."Φ22.17mm (K section)" "Φ21.58mm (L section)" "Φ21.0mm (M section)", with the cross-sectional diameter decreasing towards the tip. In the first embodiment, the diameter of the protrusion at the tip (M cross-section) of the outer peripheral inclined groove member 32A was set to Φ21.0 mm. However, this is not limited to this, and if the amount of compressed air injected from the air injection nozzle 22 is increased, an outer peripheral inclined groove member 32A with a larger diameter of the protrusion at the tip of the outer peripheral inclined groove member 32A within the range of Φ21.0 mm to Φ27.0 mm (preferably Φ21.0 mm to Φ24.0 mm) may be used.

[0038] The inclined groove 32a of the outer peripheral inclined groove member 32A is spirally inclined from the rear towards the front (see Figure 12). Specifically, the recess (lowest part) of the inclined groove 32a of the outer peripheral inclined groove member 32A is formed with a circumferential inclination of 32.6 degrees ("twist angle") from the rear end point P1 (see section A (see Figures 11 and 13(a))) to the front end point P2 (see section M (see Figures 11 and 13(m))) (see Figures 14(e) and (f)). Thus, the inclined groove 32a of the outer peripheral inclined groove member 32A is spirally inclined from the rear end towards the front and is formed to be inclined by 32.6 degrees toward the front. Here, the oblique inclination angle of the inclined groove 32a of the outer peripheral inclined groove member 32A toward the front is determined by the angle at which the "recess point on the rear end side (point P1)" is inclined toward the front ("recess point on the front end side (point P2)"). Specifically, the inclination angle of the inclined groove 32a of the outer peripheral inclined groove member 32A is determined by the "length from point P1 (the recessed point of the inclined groove 32a at the rear end of the outer peripheral inclined groove member 32A) to the tip point P3 drawn parallel to the central axis of the outer peripheral inclined groove member 32A (the length from the rear end to the tip of the outer peripheral inclined groove member 32A (18 mm))" and the "lateral length of the line connecting tip point P3 and point P2 (the recessed point of the inclined groove 32a at the tip of the outer peripheral inclined groove member 32A (11.5 mm)". Here, the "length from point P1 (the recessed point of the inclined groove 32a at the rear end of the outer peripheral inclined groove member 32A) to tip point P3 drawn parallel to the central axis of the outer peripheral inclined groove member 32A (the length from the rear end to the tip of the outer peripheral inclined groove member 32A)" is constant, but the "lateral length of the line connecting tip point P3 and point P2 (the recessed point of the inclined groove 32a at the tip of the outer peripheral inclined groove member 32A)" varies. In other words, the "horizontal length of the line connecting the tip point P3 and point P2 (the recessed point of the inclined groove 32a at the tip of the outer circumferential inclined groove member 32A)" determines the "inclination angle of the inclined groove 32a of the outer circumferential inclined groove member 32A". Furthermore, in the first embodiment, the inclined groove 32a on the outer circumferential surface of the outer circumferential inclined groove member 32A was inclined at 32.6 degrees toward the tip, but it is not limited to this, and may be inclined diagonally within the range of approximately 13.0 degrees to approximately 56.0 degrees. This will be explained in detail in Modification Example 1 described later.Here, Figure 12(a) is a diagram showing the mounting method of the components of the high-pressure injection nozzle device in the first embodiment of the present invention, Figure 12(b) is a rear view of the same high-pressure injection nozzle device, Figure 12(c) is a side view of the same high-pressure injection nozzle device, Figure 12(d) is a front view of the same high-pressure injection nozzle device, Figure 13 is a cross-sectional view A to M of Figure 11, Figure 14(a) is a front view of the outer peripheral inclined groove member of the high-pressure injection nozzle device in the first embodiment of the present invention, Figure 14(b) is a cross-sectional view FF of Figure 14(a), and Figure 14(c) is a diagram showing the diameter of the recess and the diameter of the protrusion of the inclined groove on the rear end surface of the outer peripheral inclined groove member of the high-pressure injection nozzle device in the first embodiment of the present invention. Figure 14(d) shows the diameter of the recess and protrusion of the inclined groove at the tip surface of the outer circumferential groove member of the high-pressure injection nozzle device, Figure 14(e) is a side perspective view of the outer circumferential groove member of the high-pressure injection nozzle device, and Figure 14(f) is a diagram showing the method for calculating the inclination angle of the outer circumferential groove member of the high-pressure injection nozzle device. Here, section A in Figure 11 corresponds to Figure 13(a), section B in Figure 11 corresponds to Figure 13(b), section C in Figure 11 corresponds to Figure 13(c), ... section K in Figure 11 corresponds to Figure 13(k), section L in Figure 11 corresponds to Figure 13(l), and section M in Figure 11 corresponds to Figure 13(m).

[0039] The air cover 25 has a hexagonal outer surface at its tip and a male screw formed on its rear outer surface. The hollow interior of the air cover 25 is tapered, narrowing in diameter towards the tip (see Figures 8 and 9). The air cover 25 is fitted into an outer inclined groove member 32A that is fitted to the tip of the nozzle body 24. As will be described later, an air injection nozzle 22 is formed at the tip between the inner surface of the air cover 25 and the outer surface of the outer inclined groove member 32A (see Figure 15). As a result, compressed air supplied via the air supply passage 8 in the injection rod 2 and the air passage 10 in the monitor 3 that communicates with the air supply passage 8 is injected from the air injection nozzle 22. Here, the air injection nozzle 22 communicates with two air passages 10.

[0040] The tip of the high-pressure injection nozzle device 1A is equipped with a material liquid injection nozzle 21 for injecting cement grout and an air injection nozzle 22 for injecting compressed air (see Figure 15). Specifically, the material liquid injection nozzle 21 is located on the inside of the tip of the high-pressure injection nozzle device 1A, and the air injection nozzle 22 is located on the outside. In this way, when cement grout and compressed air are injected at high pressure from the high-pressure injection nozzle device 1A, the cement grout is injected from the inside of the high-pressure injection nozzle device 1A, and compressed air is injected from the outside (outer periphery). This forms a gas phase film of compressed air around the cement grout jet, which increases the injection reach compared to when there is no gas phase film of compressed air. The details will be described later.

[0041] The liquid material injection nozzle 21 is formed at the tip of the nozzle body portion 24. The air injection nozzle 22 is formed from the outer surface of the outer inclined groove member 32A and the inner surface of the air cover 25, and communicates with the air passage 10 inside the monitor 3 (see Figure 6(a)). In the first embodiment, the air injection nozzle 22 is formed from the outer surface of the outer inclined groove member 32A and the inner surface of the air cover 25, but it is not limited to this. Any other form of air injection nozzle is acceptable as long as it communicates with the air passage 10 inside the monitor 3, is configured to surround the outer diameter of the tip of the nozzle body portion 24, and has a cross-sectional area that decreases from the air passage 10 inside the monitor 3 toward the tip, thereby injecting compressed air at high speed.

[0042] Next, the assembly method of the injection rod 2, monitor 3, and high-pressure injection nozzle device 1A will be explained using Figures 5 and 7.

[0043] First, the lower end of the injection rod 2 is inserted into the upper part of the monitor upper tube 35 (see Figure 5). When inserting the injection rod 2, the semicircular injection rod projection 2c formed on the lower end of the injection rod outer tube 2b and the semicircular monitor upper tube inner projection 3c formed on the upper part of the monitor upper tube 35 are fitted together, and the monitor upper tube 35 and the injection rod 2 are aligned in the circumferential direction, thereby attaching the monitor 3 to the injection rod 2. Then, the coupling pin 36 is inserted into the coupling pin insertion hole 19a formed by the coupling pin injection rod recess 20a at the bottom of the injection rod outer tube 2b and the coupling pin monitor recess 20b at the top of the monitor upper tube 35, thereby connecting the monitor 3 to the injection rod 2. Specifically, the coupling pin 36 is composed of a spring pin 36a and a spring pin 36b. First, the spring pin 36b is inserted into the coupling pin insertion hole 19a via the coupling pin insertion port 19 at the bottom of the injection rod 2. Then, the spring pin 36a is press-fitted into the hollow portion of the spring pin 36b that has been inserted into the coupling pin insertion hole 19a. In this way, the monitor 3 is coupled to the injection rod 2 by the coupling pin 36 being inserted into the coupling pin insertion hole 19a formed by the coupling pin injection rod recess 20a at the bottom of the injection rod outer tube 2b and the coupling pin monitor recess 20b at the top of the monitor upper tube 35. In the first embodiment, the upper and lower parts of the upper end of the upper part of the monitor upper tube 35 were described as a single unit. However, the upper and lower parts of the upper ends of the four air passages 10 formed inside the monitor upper tube 35 may be configured as separate parts. By configuring them as separate parts in this way, the formation of the four air passages 10 inside the monitor upper tube 35 becomes easier.

[0044] Next, the monitor lower pipe 39, which incorporates the differential pressure valve 34, is attached to the lower end of the monitor upper pipe 35 (see Figures 3 and 5). Specifically, the monitor lower pipe 39 is attached to the monitor upper pipe 35 by screwing together the male thread on the upper outer circumference of the monitor lower pipe 39 with the female thread on the inner circumference of the lower end of the monitor upper pipe 35.

[0045] Next, the high-pressure spray nozzle device 1A is attached to the nozzle body mounting hole 23 formed on the side of the monitor 3. Specifically, the high-pressure spray nozzle device 1A is attached to the nozzle body mounting hole 23 of the monitor 3 in the following steps (1) to (3). The procedure for attaching the high-pressure spray nozzle device 1A will be described below with reference to Figure 7. Here, Figure 7 is a cross-sectional view showing the method for attaching the high-pressure spray nozzle device in the first embodiment of the present invention.

[0046] (1) First, the nozzle body extension 27 is inserted into the nozzle body mounting hole 23. This fits the nozzle body extension 27 into the nozzle body mounting hole 23. The nozzle body extension 27 fitted into the nozzle body mounting hole 23 is installed so as to protrude into the cement milk / water channel 9 (hardening agent liquid channel) inside the monitor 3 (see Figure 6(a)). In the first embodiment, the nozzle body extension 27 is installed so as to protrude into the cement milk / water channel 9 (hardening agent liquid channel) inside the monitor 3, but it may also be installed in a shape that does not protrude into the cement milk / water channel 9 (hardening agent liquid channel) inside the monitor 3, or it may be installed so as to protrude to approximately the center of the cement milk / water channel 9 (hardening agent liquid channel) inside the monitor 3.

[0047] (2) Next, the nozzle body 26 is inserted into the nozzle body mounting hole 23. When the nozzle body 26 is inserted into the nozzle body mounting hole 23, the nozzle body 26 is attached to the monitor 3 by screwing together the male thread formed on the outer circumference of the rear end of the nozzle body 26 with the female thread formed in the nozzle body mounting hole 23 of the monitor 3.

[0048] (3) Next, the outer circumferential groove member 32A and the air cover 25 are fitted in order from the tip of the nozzle body 26, and the air cover 25 (including the outer circumferential groove member 32A) is attached to the monitor 3 by screwing the male threads formed on the outer circumference of the air cover 25 with the female threads formed in the air cover mounting holes 43 on the inner circumference of the side of the monitor 3.

[0049] As described above, since the high-pressure injection nozzle device 1A can be detachably attached to the monitor 3, the high-pressure injection nozzle device 1A can be freely replaced according to the soil type, etc., and the high-pressure injection nozzle device 1A can be attached to the monitor 3 in a simple manner.

[0050] In this way, by providing the rear end inner diameter portion 28 of the nozzle body extension 27 to protrude into the cement grout / water channel 9 (hardening agent liquid channel) inside the monitor 3, a sufficiently long straight distance can be secured inside the nozzle body 24, and the generation of turbulence in the cement grout flowing inside the nozzle body 24 can be reduced. As a result, the cutting ability of the cement grout sprayed from the tip of the nozzle body 24 can be increased, destroying the structural integrity of the ground and allowing the cement grout to be sprayed over long distances. Furthermore, as described above, the total cross-sectional area of ​​the channels divided by the channel division portion 31 is 40% of the forward outer diameter cross-sectional area of ​​the rear end inner diameter portion 28 (outer diameter cross-sectional area of ​​the reduced diameter portion of the rear end inner diameter portion 28), so that the cement grout flowing through the rear end inner diameter portion 28 of the nozzle body 24 is divided into the respective spaces divided by the channel division portion 31 and sent towards the tip while being compressed with an appropriate compressive force. Furthermore, the cement grout, which is compressed and sent towards the tip, becomes laminar in each space divided by the flow channel division section 31 while increasing in velocity. This allows the cement grout passing through the nozzle body 24 to become a fine laminar flow, increasing the cutting ability of the cement grout sprayed from the tip of the nozzle body 24, thereby destroying the structural integrity of the ground and allowing the cement grout to be sprayed over longer distances. The same applies when the total cross-sectional area of ​​the flow channels divided by the flow channel division section 31 accounts for 40% to 60% of the outer diameter cross-sectional area of ​​the rear end inner diameter section 28 (the outer diameter cross-sectional area of ​​the reduced diameter portion of the rear end inner diameter section 28).

[0051] Furthermore, as described above, the area of ​​the approximately central part of the flow channel division section 31 of the rear end inner diameter section 28 is formed to occupy 2% to 20% of the outer diameter cross-sectional area of ​​the front end inner diameter section 28 (outer diameter cross-sectional area of ​​the reduced diameter portion of the rear end inner diameter section 28). As a result, the cement milk flowing through the rear end inner diameter section 28 of the nozzle body section 24 is further laminarized in each space divided by the flow channel division section 31, and then reduced in diameter in the hollow space of the intermediate inner diameter section 29 where no tangible objects exist, before being sent towards the tip. This increases the cutting ability of the cement milk sprayed from the material liquid injection nozzle 21 (the tip of the nozzle body section 24), and the cement This allows the cement milk to be sprayed over longer distances, and the cement milk flowing through the approximate center of the rear end inner diameter portion 28 of the nozzle body 24 collides with the approximate center of the flow path division portion 31. The collided cement milk flows into each of the flow paths divided by the flow path division portion 31, increasing in velocity as it is sent along the inner surface of the reduced diameter intermediate inner diameter portion 29. This reduces the thickness of the boundary layer caused by turbulence on the inner surface of the intermediate inner diameter portion 29, making the cement milk passing through the nozzle body 24 a finer laminar flow and reducing the thickness of the boundary layer caused by turbulence on the inner surface of the intermediate inner diameter portion 29. As a result, the cement milk sprayed from the tip of the nozzle body 24 is sprayed at approximately the same velocity across almost the entire surface of the nozzle opening, allowing the region where the velocity of the cement milk sprayed from the nozzle opening of the material liquid spraying nozzle 21 at the tip of the nozzle body 24 does not decrease (potential core region) to be maintained for a longer period. This allows the cement milk to be sprayed over longer distances, and also increases the cutting ability of the hardening material liquid sprayed from the tip of the nozzle body, enabling the destruction of the soil's structural integrity. Here, the potential core region is the region in which the velocity of the cement milk injected from the liquid injection nozzle 21 does not decrease. In this potential core region, the injection pressure at the time of injection from the nozzle 21 is maintained, forming what could be called the core of the jet, and the diameter of the cement milk injection stream injected from the liquid injection nozzle 21 is reduced.

[0052] In this way, the cement grout flowing through the inner diameter portion 28 at the rear end of the nozzle body portion 24 (nozzle body extension portion 27) is divided into separate spaces by the flow path division portion 31 and sent towards the tip, so that the cement grout can be made to flow more finely and laminarily in each space divided by the flow path division portion 31. As a result, the cutting ability of the cement grout sprayed from the material liquid injection nozzle 21 at the tip of the nozzle body portion 24 can be increased, destroying the structural integrity of the ground and allowing the cement grout to be sprayed over longer distances.

[0053] Next, using Figures 1, 16, and 17, we will briefly describe the construction procedure using a ground improvement device equipped with a monitor 3 fitted with a high-pressure injection nozzle device 1A according to the first embodiment of the present invention.

[0054] First, the drilling location for the injection rod 2 is determined, and then water (liquid) is injected from the tip nozzle 4 of the monitor 3 attached to the tip of the injection rod 2 at that location to drill to a predetermined depth (see Figure 1). In Figure 1, water is also injected from the high-pressure injection nozzle device 1A, but during ground excavation, water (liquid) is not injected from the high-pressure injection nozzle device 1A, and the ground is drilled by injecting water (liquid) from the tip nozzle 4 of the monitor 3.

[0055] After drilling to a predetermined depth, the injection rod 2 is rotated upward while cement grout is injected from the material liquid injection nozzle 21 and compressed air from the air injection nozzle 22 (see Figure 16). Specifically, the injection rod 2 is rotated clockwise while cement grout and compressed air are injected simultaneously from the injection nozzles (material liquid injection nozzle 21 and air injection nozzle 22). In this embodiment, since the outer surface of the outer surface inclined groove member 32A has inclined grooves 32a of the same shape that are inclined diagonally in approximately the same direction toward the tip, the compressed air injected from the air injection nozzle 22 (the tip between the outer surface of the outer surface inclined groove member 32A and the inner surface of the air cover 25) will revolve around the cement grout injected from the material liquid injection nozzle 21 (the tip of the nozzle body 24). As a result, the cutting ability of the cement grout injected from the material liquid injection nozzle 21 (the tip of the nozzle body 24) is increased, the structural integrity of the ground is destroyed, and the cement grout can be injected over a greater distance. Furthermore, as described above, since an inclined groove 32a is provided on the outer surface of the outer inclined groove member 32A, the compressed air injected from the air injection nozzle 22 becomes a swirling flow directed towards the center, forming a compressed air swirling flow that presses around the hardening liquid. This makes it difficult for the compressed air swirling flow around the cement milk to disperse, and also makes it difficult for the cement milk injection flow to increase significantly in the radial direction immediately after injection from the material liquid injection nozzle 21. This maintains the straightness of the cement milk injection flow and prevents its speed from decreasing, allowing the region where the velocity of the cement milk injected from the material liquid injection nozzle 21 does not decrease (potential core region) to be maintained for a longer period, and enabling the cement milk to be injected over a longer distance. Here, Figure 16 is a diagram showing the injection state from the tip nozzle of the high-pressure injection nozzle device in the first embodiment of the present invention.

[0056] Furthermore, the high-pressure injection nozzle device 1A repeats the cycle of rotating injection → pulling up the injection rod 2 → rotating injection until injection is complete. In this way, as the injection rod 2 is pulled up while rotating injection is performed, the "soil and cement grout mixture" accumulated below is agitated by the swirling compressed air flow that swirls around the cement grout injected from the liquid injection nozzle 21 (the tip of the nozzle body 24). This makes it easier for the soil and cement grout mixture to rise, improving the airlift effect, and allowing the agitated soil and cement grout mixture to be efficiently discharged to the ground as sludge (see Figure 17). Furthermore, even if cavities (air bubbles) due to cavitation exist around the outer periphery of the cement milk sprayed from the liquid injection nozzle 21, the compressed air injected from the air injection nozzle 22 (the tip between the inner surface of the air cover 25 and the outer surface of the outer inclined groove member 32A) swirls around the cement milk, completely enveloping it without gaps. This makes it difficult for the cement milk to come into contact with the ground, preventing the collapse of cavities present around the outer periphery of the cement milk injection flow (see Figure 16). As a result, the region where the velocity of the cement milk sprayed from the liquid injection nozzle 21 does not decrease (potential core region) can be maintained for a longer period, allowing the cement milk to be sprayed over longer distances. In other words, because the cement milk is completely enveloped by the compressed air injected from the air injection nozzle 22 while swirling, it becomes difficult for the cement milk to come into contact with the ground, preventing the collapse of cavities generated around the outer periphery of the cement milk. This allows the region where the velocity of the cement grout injected from the material liquid injection nozzle 21 does not decrease (potential core region) to be maintained for a longer period, and the cement grout can be injected over a longer distance. Here, Figure 17(a) shows the state in which the mud around the monitor is discharged to the ground, and Figure 17(b) shows the state in which the mud around the high-pressure injection nozzle device is discharged to the ground.

[0057] Next, with the injection rod 2 having made one full rotation, the injection rod 2 is raised to a predetermined length (for example, 10 cm or less (preferably 5.0 cm (more preferably 2.5 cm))). Then, the cycle of clockwise rotation and injection → raising the injection rod 2 → clockwise rotation and injection → raising the injection rod 2 → clockwise rotation and injection → raising the injection rod 2 is repeated until the injection from the injection nozzles (liquid material injection nozzle 21, air injection nozzle 22) is complete. In the first embodiment, the injection rod 2 was rotated clockwise, but it is not limited to this, and the injection rod 2 may also be rotated counterclockwise. In this case, the inclined groove 32a of the outer peripheral inclined groove member 32A is inclined diagonally to the left toward the tip.

[0058] Next, the injection rod 2 is lifted out of the borehole by a crane or similar device and removed from the borehole. Following the above construction procedure, a cylindrical solidified body is formed underground.

[0059] Next, the jet flow of the high-pressure injection nozzle device 1A using the outer peripheral inclined groove member 32A (swivel inner C) of this embodiment will be explained in comparison with the jet flow of the high-pressure injection nozzle device 100 using an air cover (swivel air cover B) and the jet flow of the high-pressure injection nozzle device using an air cover without an inclined groove (standard air cover A) in the background art (Japanese Patent Publication No. 6754914), using Figures 18 and 19. In this comparative example, instead of injecting "cement milk" from the material liquid injection nozzle, "injection water" is injected from the material liquid injection nozzle to compare the respective jet flows. Here, "standard air cover A" is "an air cover without an inclined groove," "swivel air cover B" is "an air cover 125 with an inclined groove 125a formed on its inner circumferential surface," and "swivel inner C" is "an outer peripheral inclined groove member 32A with an inclined groove 32a formed on its outer circumferential surface." Figure 18 shows the "standard deviation of impact load" of the water jet sprayed from the material liquid injection nozzle of the high-pressure injection nozzle device, and Figure 19 shows the "average value of impact load" of the water jet sprayed from the material liquid injection nozzle of the high-pressure injection nozzle device. In Figure 18, the horizontal axis is "nozzle-target distance (distance between the high-pressure injection nozzle device and the target)" and the vertical axis is "standard deviation (standard deviation of impact load)". In Figure 18, the "magnitude of deviation of the water jet sprayed from the target" is shown for "predetermined distance intervals from the high-pressure injection nozzle device to the target". In Figure 19, the horizontal axis is "nozzle-target distance (distance between the high-pressure injection nozzle device and the target)" and the vertical axis is "average value of impact load". The "average value of impact load when the water jet sprayed from the material liquid injection nozzle of the high-pressure injection nozzle device collides with the target" is shown for "predetermined distance intervals from the high-pressure injection nozzle device to the target".

[0060] As shown in Figure 18, at all distances from the high-pressure injection nozzle device to the target ("1600mm, 1800mm, 2000mm, 2200mm"), the water injected from the liquid injection nozzle 21 of the high-pressure injection nozzle device 1A using the outer peripheral inclined groove member 32A (swivel inner C) of this embodiment has a smaller "standard deviation of impact load" than the water injected from the liquid injection nozzle of the high-pressure injection nozzle devices using "standard air cover A" and "swivel air cover B".

[0061] Thus, the reason why the water sprayed from the liquid injection nozzle 21 of the high-pressure injection nozzle device 1 using the outer peripheral inclined groove member 32A (swivel inner C) of this embodiment has a smaller standard deviation of impact load (movement from target ("up-down reciprocating movement movement movement" and "left-right reciprocating movement movement movement")) than the water sprayed from the liquid injection nozzle of the high-pressure injection nozzle device using the "standard air cover A" and "swivel air cover B" is because the water sprayed from the liquid injection nozzle of the high-pressure injection nozzle device 1 using the outer peripheral inclined groove member 32A (swivel inner In C), the outer circumferential surface is tapered toward the tip, and an inclined groove 32a is formed that slopes diagonally in approximately the same direction toward the tip. Therefore, the inclined groove 32a provided on the outer circumferential surface of the outer circumferential inclined groove member 32A causes the compressed air injected from the air injection nozzle 22 to become a swirling flow toward the center, forming a compressed air swirling flow that presses around the injected water. This makes it difficult for the compressed air swirling flow around the injected water to disperse, and thus makes it difficult for the injected water injected from the liquid injection nozzle 21 to increase significantly in the radial direction. As a result, the outer circumferential inclined groove member 32A (swirling inner C) of the high-pressure injection nozzle device 1 of this embodiment has smaller movement deviations from the target of the injected water injected from the liquid injection nozzle 21 of the high-pressure injection nozzle device 1 ("up-down reciprocating movement deviations" and "left-right reciprocating movement deviations") than the "standard air cover A" and "swirling air cover B".

[0062] Furthermore, as shown in Figure 19, the water sprayed from the liquid material spray nozzle 21 of the high-pressure spray nozzle device 1A using the outer peripheral inclined groove member 32A (swivel inner C) of this embodiment has a higher average impact load (impact force on the target) for the water sprayed from the liquid material spray nozzle at all distances from the high-pressure spray nozzle device to the target ("1600 mm, 1800 mm, 2000 mm, 2200 mm") than the water sprayed from the liquid material spray nozzle of the high-pressure spray nozzle devices using the "standard air cover A" and "swivel air cover B".

[0063] Thus, the reason why the water sprayed from the liquid injection nozzle 21 of the high-pressure injection nozzle device 1 using the outer peripheral inclined groove member 32A (swirl inner C) of this embodiment has a greater impact force on the target than the "standard air cover A" and "swirl air cover B" is thought to be because the outer peripheral inclined groove member 32A (swirl inner C) of the high-pressure injection nozzle device 1 of this embodiment has an outer peripheral surface that narrows in diameter towards the tip and has an inclined groove 32a that is obliquely inclined in approximately the same direction toward the tip. As a result, the compressed air sprayed from the air injection nozzle 22 becomes a swirling flow toward the center due to the inclined groove 32a provided on the outer peripheral surface of the outer peripheral inclined groove member 32A, forming a compressed air swirling flow that presses around the water spray. This makes it difficult for the compressed air swirling flow around the water spray to disperse, and thus makes it difficult for the water sprayed from the liquid injection nozzle 21 to increase significantly in the radial direction. As a result, the outer circumferential inclined groove member 32A (swivel inner C) of the high-pressure injection nozzle device 1 of this embodiment has a larger average value of the impact load of the injected water sprayed from the material liquid injection nozzle (impact force on the target) than the "standard air cover A" and "swivel air cover B", and the impact force of the injected water sprayed from the material liquid injection nozzle on the target is greater.

[0064] As described above, compared to "Standard Air Cover A" and "Swivel Air Cover B", "Swivel Inner C" exhibits smaller movement and oscillation of the injected water from the liquid injection nozzle of the high-pressure injection nozzle device relative to the target ("up-down reciprocating movement and oscillation" and "left-right reciprocating movement and oscillation"). Furthermore, it exhibits a greater impact force on the target from the injected water from the liquid injection nozzle. Therefore, even when the injected water from the liquid injection nozzle is cement grout, the movement and oscillation of the cement grout injected from the liquid injection nozzle of the high-pressure injection nozzle device relative to the target are smaller, and the impact force on the target from the cement grout injected from the liquid injection nozzle is greater. Consequently, compared to "Standard Air Cover A" and "Swivel Air Cover B", "Swivel Inner C" can maintain the region where the velocity of the cement grout injected from the liquid injection nozzle does not decrease (potential core region) for a longer period, and can inject the cement grout over longer distances.

[0065] (Second Embodiment) Next, a second embodiment of the high-pressure injection nozzle device of the present invention will be described with reference to Figures 20 to 23. Here, Figure 20(a) is an external perspective view of a monitor to which the high-pressure injection nozzle device of the second embodiment of the present invention is attached, Figure 20(b) is a front view of the same high-pressure injection nozzle device, Figure 21 is a cross-sectional view of JJ of Figure 20(b), Figure 22(a) is a front view of the outer circumferential inclined groove member of the high-pressure injection nozzle device of the second embodiment of the present invention, Figure 22(b) is a cross-sectional view of KK of Figure 22(a), and Figure 23 is a diagram showing the injection state from the injection nozzle of the high-pressure injection nozzle device of the second embodiment of the present invention.

[0066] The difference between the second embodiment and the first embodiment is that in the first embodiment, the hollow outer circumferential groove member 32A is formed with an inner diameter approximately the same as the outer diameter of the nozzle body 26, and compressed air is injected while the outer circumferential groove member 32A does not rotate in the circumferential direction of the outer surface of the nozzle body 26 during compressed air injection, whereas in the second embodiment, the outer circumferential groove member 50 is formed with an inner diameter larger than the outer diameter of the nozzle body 26, and compressed air is injected while the outer circumferential groove member 50 rotates in the circumferential direction of the outer surface of the nozzle body 26 during compressed air injection (see Figure 20). Specific details will be described later. In the second embodiment, the same reference numerals are used for components identical to those in the first embodiment, and they perform the same functions and effects, so their explanation is omitted.

[0067] The outer circumferential groove member 50 has four projections 50b formed on its inner circumferential surface at equal intervals along the circumference, and its inner diameter is larger than the outer diameter of the tip of the nozzle body 26. Furthermore, the outer circumferential surface of the outer circumferential groove member 50 (the most protruding part) is formed as a curved outer circumferential surface portion 50c, which protrudes outward and abuts against the inner circumferential surface of the air cover 25 (see Figure 20(b)). When the outer circumferential groove member 50 is inserted from the tip direction of the nozzle body 26, the projections 50b on the inner circumferential surface come into contact with the nozzle body 26. (Nozzle body part 24) It is in contact with the outer circumferential surface, and the inner circumferential surface of the outer circumferential inclined groove member 50 and the nozzle body 26 (Nozzle body part 24) A gap is formed in the circumferential direction between the inner surface of the outer circumferential inclined groove member 50 and the outer circumferential surface of the nozzle body 26. In this way, by having a gap between the inner surface of the outer circumferential inclined groove member 50 and the outer circumferential surface of the nozzle body 26, when the inclined surface of the inclined groove 50a of the outer circumferential inclined groove member 50 is pressed by compressed air supplied from the air passage 10 in the monitor 3, the outer circumferential inclined groove member 50 can be rotated in the circumferential direction of the outer circumferential surface of the nozzle body 26. In this embodiment, four protrusions 50b are formed on the inner circumferential surface of the outer circumferential inclined groove member 50 at equal intervals on the circumference, but it is not limited to this, and three to eight may be formed, and they do not have to be formed at equal intervals on the circumference.

[0068] Furthermore, since the curved outer surface portion 50c (curved outer surface (outer surface)) of the outer inclined groove member 50 is formed in a curved shape, the outer inclined groove member 50 is formed in a curved shape. (Nozzle body part 24) When the outer surface rotates in the circumferential direction, the contact area between the curved outer surface portion 50c of the outer inclined groove member 50 and the inner surface of the air cover 25 decreases, and the resistance force between the rotating curved outer surface portion 50c of the outer inclined groove member 50 and the inner surface of the air cover 25 decreases, so the outer inclined groove member 50 moves towards the nozzle body 26 (Nozzle body part 24) The outer surface can be rotated at a higher speed in the circumferential direction, and compressed air can be ejected more strongly from the air injection nozzle 22 while swirling.

[0069] Furthermore, the inner surface of the outer circumferential inclined groove member 50 and the nozzle body 26 (Nozzle body part 24) An air passage 49 is formed between the outer surfaces of the outer inclined groove member 50 and the outer surface of the nozzle body 26, and a compressed air nozzle 48 is formed at the tip of the air passage 49 (see Figure 21). Since the opening area of ​​this compressed air nozzle 48 is smaller than the opening area of ​​the air injection nozzle 22, the compressed air injected from the compressed air nozzle 48 can be injected at a higher speed than the compressed air injected from the air injection nozzle 22. In this way, the compressed air supplied from the air passage 10 in the monitor 3 is injected at high speed from the compressed air nozzle 48 at the tip of the air passage 49, via the air passage 49 between the inner surface of the outer inclined groove member 50 and the outer surface of the nozzle body 26.

[0070] In this way, the inner surface of the outer circumferential inclined groove member 50 and the nozzle body 26 (Nozzle body part 24)Compressed air is injected at high speed from the compressed air injection port 48 at the tip of the air passage 49 between the outer surface and the material liquid injection nozzle 21, forming a compressed air injection layer that surrounds the cement milk injected from the material liquid injection nozzle 21. The compressed air swirling flow injected from the air injection nozzle 22 swirls around the cement milk injected from the material liquid injection nozzle 21 via the compressed air injection layer, causing the cement milk injected from the material liquid injection nozzle 21 to be pressed more strongly towards the center via the compressed air injection layer. This makes it difficult for the cement milk injection flow immediately after injection from the material liquid injection nozzle 21 to come into contact with the surrounding ground (see Figure 23). As a result, the region in which the velocity of the cement milk injected from the material liquid injection nozzle 21 does not decrease (potential core region) can be maintained for a longer period, and the cement milk can be injected over a longer distance.

[0071] Furthermore, the projection 50b on the inner surface of the outer circumferential inclined groove member 50 is located on the nozzle body 26 (Nozzle body part 24) By contacting the outer surface, the nozzle body 26 (Nozzle body part 24) The outer circumferential inclined groove member 50, which rotates in the circumferential direction of the outer surface, becomes less prone to movement, and the inner surface of the outer circumferential inclined groove member 50 and the nozzle body 26 (Nozzle body part 24)The thickness of the compressed air injected from the compressed air injection port 48 at the tip of the air passage 49 between the outer surface and the nozzle body 26 can be kept uniform. As a result, the compressed air injected from the compressed air injection port 48 can completely cover the cement milk injection stream, making it less likely for the cement milk injection stream to come into contact with the surrounding ground. In the second embodiment, the outer circumferential inclined groove member 50 is made to rotate around the nozzle body 26 (nozzle body portion 24), but the invention is not limited to this, and the outer circumferential inclined groove member 50 may not rotate around the nozzle body 26. Even in this case, the compressed air injected from the compressed air nozzle 48 forms a compressed air injection layer that surrounds the cement grout injected from the material liquid injection nozzle 21. The compressed air swirling flow injected from the air injection nozzle 22 swirls around the cement grout injected from the material liquid injection nozzle 21 via the compressed air injection layer. As a result, the cement grout injected from the material liquid injection nozzle 21 is pressed more strongly towards the center by the compressed air swirling flow injected from the air injection nozzle 22 via the compressed air injection layer, making it difficult for the cement grout injection flow immediately after injection from the material liquid injection nozzle 21 to come into contact with the surrounding ground. This allows the region where the velocity of the cement grout injected from the material liquid injection nozzle 21 does not decrease (potential core region) to be maintained for a longer period, and the cement grout can be injected over a longer distance.

[0072] As described above, in this embodiment, compressed air is injected from the compressed air injection port 48 at the tip of the air passage 49, and compressed air is injected from the air injection nozzle 22 while the outer peripheral inclined groove member 50 rotates. As a result, the area around the cement milk injection flow is completely covered by the compressed air injected from the compressed air injection port 48, and as the outer peripheral inclined groove member 50 rotates at high speed around the nozzle body 26, the compressed air is injected more strongly from the air injection nozzle 22 while swirling. Consequently, the cement milk injected from the material liquid injection nozzle 21 is strongly pressed towards the center through the compressed air injection layer by the swirling compressed air flow injected from the air injection nozzle 22. This allows the region where the velocity of the cement milk injected from the material liquid injection nozzle 21 does not decrease (potential core region) to be maintained for a longer period, and the cement milk can be injected over a longer distance.

[0073] Next, a modified example of the high-pressure injection nozzle device of the present invention will be described. Here, the length of the high-pressure injection nozzle device is determined by the diameter of monitor 3, and since the high-pressure injection nozzle device of the present invention is used with a length of 20 mm to 40 mm, the modified example below will describe an outer circumferential inclined groove member corresponding to a high-pressure injection nozzle device with a length of 20 mm to 40 mm.

[0074] (Variation 1) First, a modified example 1 of the high-pressure injection nozzle device of the present invention will be described using Figure 24. Here, Figure 24(a) is a front view of the outer circumferential inclined groove member of the high-pressure injection nozzle device in modified example 1 of the present invention, Figure 24(b) is a cross-sectional view of Figure 24(a), Figure 24(c) shows the diameter of the recess and the diameter of the convex portion of the inclined groove on the rear end surface of the outer circumferential inclined groove member of the high-pressure injection nozzle device in modified example 1 of the present invention, Figure 24(d) shows the diameter of the recess and the diameter of the convex portion of the inclined groove on the front end surface of the outer circumferential inclined groove member of the same high-pressure injection nozzle device, Figure 24(e) is a side perspective view of the outer circumferential inclined groove member of the same high-pressure injection nozzle device, and Figure 24(f) shows a method for calculating the inclination angle of the outer circumferential inclined groove member of the same high-pressure injection nozzle device.

[0075] The difference between Modified Example 1 and the above embodiment is that in the above embodiment, the outer peripheral inclined groove member 32A has a length of 18 mm, and the recessed point of the inclined groove 32a of the outer peripheral inclined groove member 32A is inclined at 32.6 degrees ("twist angle") in the circumferential direction from the rear end point P1 to the front end point P2 (see Figures 14(e) and (f)), whereas in Modified Example 1, the outer peripheral inclined groove member 32B has a length of 25 mm, and the recessed point of the inclined groove 32b of the outer peripheral inclined groove member 32B is formed inclined at 13.0 degrees ("twist angle") in the circumferential direction from the rear end point PP1 to the front end point PP2 (see Figure 24).

[0076] In other words, when a monitor 3 with a diameter of 140 mm is used, the outer circumferential inclined groove member 32B is formed with a length of 25 mm from the recessed point (PP1 point) of the inclined groove 32b at the rear end of the outer circumferential inclined groove member 32B to the tip point PP3 drawn parallel to the central axis of the outer circumferential inclined groove member 32B (length from the rear end to the tip of the outer circumferential inclined groove member 32B), and the length of the line connecting the tip point PP3 and the recessed point (PP2 point) of the inclined groove 32B at the tip of the outer circumferential inclined groove member 32B is formed to be 5.7 mm. Furthermore, the inclined groove 32b of this outer circumferential inclined groove member 32B is formed with the recessed point inclined circumferentially at a rate of 13.0 degrees ("twist angle") from the rear end to the tip (see Figure 24). In other words, the inclined groove 32b of the outer circumferential inclined groove member 32B is formed to incline spirally from the rear end to the tip and to incline 13.0 degrees toward the tip.

[0077] Thus, when using an outer peripheral inclined groove member 32B (length 25 mm) which is longer than the outer peripheral inclined groove member 32A (length 18 mm) used in the above embodiment, the outer peripheral inclined groove member 32B can be formed such that the recessed points are inclined in the circumferential direction from the rear end to the front end to a "twist angle" of 13.0 degrees, taking into consideration the spacing between the inclined grooves 32b of the outer peripheral inclined groove member 32B.

[0078] (Modification 2) Next, a modified example 2 of the high-pressure injection nozzle device of the present invention will be described with reference to Figure 25. Here, Figure 25(a) is a front view of the outer circumferential inclined groove member of the high-pressure injection nozzle device in modified example 2 of the present invention, Figure 25(b) is an HH cross-sectional view of Figure 25(a), Figure 25(c) shows the diameter of the recess and the diameter of the convex portion of the inclined groove on the rear end surface of the outer circumferential inclined groove member of the high-pressure injection nozzle device, Figure 25(d) shows the diameter of the recess and the diameter of the convex portion of the inclined groove on the front end surface of the outer circumferential inclined groove member of the high-pressure injection nozzle device, Figure 25(e) is a side perspective view of the outer circumferential inclined groove member of the high-pressure injection nozzle device, and Figure 25(f) shows a method for calculating the inclination angle of the outer circumferential inclined groove member of the high-pressure injection nozzle device.

[0079] The difference between Modified Example 2 and the above embodiment is that in the above embodiment, the outer peripheral inclined groove member 32A has a length of 18 mm, and the recessed points of the inclined groove 32a of the outer peripheral inclined groove member 32A are inclined at 32.6 degrees ("twist angle") in the circumferential direction from the rear end point P1 to the front end point P2 (see Figures 14(e) and (f)), whereas in Modified Example 2, the outer peripheral inclined groove member 32C has a length of 10 mm, and the recessed points of the inclined groove 32c of the outer peripheral inclined groove member 32C are formed with an inclination of 56.0 degrees ("twist angle") in the circumferential direction from the rear end point PPP1 to the front end point PPP2 (see Figure 25).

[0080] In other words, when a monitor 3 with a diameter of 50 mm to 60 mm is used, the outer circumferential inclined groove member 32C is formed with a length of 10 mm from the recessed point (PPP1 point) of the inclined groove 32c at the rear end of the outer circumferential inclined groove member 32C to the tip point PPP3 drawn parallel to the central axis of the outer circumferential inclined groove member 32C (length from the rear end to the tip of the outer circumferential inclined groove member 32C), and the length of the horizontal line connecting the tip point PPP3 and the recessed point (PPP2 point) of the inclined groove 32c at the tip of the outer circumferential inclined groove member 32C is formed with a length of 14.7 mm. Furthermore, the inclined groove 32c of this outer circumferential inclined groove member 32C is formed with the recessed point inclined 56.0 degrees ("twist angle") in the circumferential direction from the rear end to the tip (see Figure 25). That is, the inclined groove 32c of the outer circumferential inclined groove member 32C is formed to incline spirally from the rear end to the tip and to incline 56.0 degrees toward the tip.

[0081] Thus, when using an outer peripheral inclined groove member 32C (length 10 mm) which is shorter in length than the outer peripheral inclined groove member 32A (length 18 mm) used in the above embodiment, the inclined grooves 32c of the outer peripheral inclined groove member 32C can be formed so that the recessed points are inclined in the circumferential direction from the rear end to the front end to a "twist angle" of 56.0 degrees, taking into consideration the spacing between the inclined grooves 32c of the outer peripheral inclined groove member 32C.

[0082] From the above modified examples 1 and 2, it can be seen that as the size of the high-pressure injection nozzle device changes with the size of the monitor 3, the "length from the recessed points (PP1, PPP1) of the inclined grooves (32b, 32c) at the rear end of the outer circumferential inclined groove members (32B, 32C) to the tip points (PP3, PPP3) drawn parallel to the central axis of the outer circumferential inclined groove members (32B, 32C)" and the "lateral length of the line connecting the tip points (PP3, PPP3) and the recessed points (PP2, PPP2) of the inclined grooves (32b, 32c) at the tip of the outer circumferential inclined groove members (32B, 32C)" change, and the "inclination angle ("twist angle") of the inclined grooves (32b, 32c) of the outer circumferential inclined groove members (32B, 32C)" determined by these changes changes within a range of approximately 13.0 degrees to approximately 56.0 degrees.

[0083] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. Furthermore, the scope of the present invention is indicated by the claims rather than by the foregoing description, and all modifications within the meaning and scope of the claims are intended to be included. [Explanation of Symbols]

[0084] 1A High-pressure injection nozzle device 1B High-pressure injection nozzle device 2 injection rods 2a Injection rod inner tube 2b Injection rod outer tube 2c Injection rod projection 3 monitors 3a Monitor Inner Tube 3b Monitor outer tube 3c Protrusion inside the upper tube of the monitor 4. Tip nozzle 5. Work equipment 6 swivels 7. Cement grout and water supply channel 8. Air supply path 9. Water channel for both cement grout and water supply 10 Airflow channels 11 Water sources 12. Air supply source 13. Cement milk supply sources 14 Water supply hose 15. Air supply hose 16. Cement milk supply hose 19. Coupling pin insertion slot 19a Coupling pin insertion hole 20a Coupling pin injection rod recess 20b Coupling pin monitor recess 21. Liquid spray nozzle 22 Air injection nozzles 23 Nozzle body mounting hole 24 Nozzle body 25 Air cover 26 Nozzle body 27 Nozzle body extension 28 Rear end inner diameter part 29 Intermediate inner diameter section 30 Inner diameter of the tip 31 Flow channel division section 32A Outer circumference inclined groove member 32a Slant groove 32B Outer circumference inclined groove member 32b Slant groove 32C Outer circumference inclined groove member 32c inclined groove 34 Differential pressure valve 35 Monitor upper tube 36 coupling pins 36a Spring pin 36b Spring pin 39 Monitor lower tube 43 Air cover mounting holes 48 Compressed air nozzle 49 Airflow channels 50 Outer Peripheral Inclined Trench Material 50a Inclined Ditch 50b Protrusion 50c Curved peripheral face

Claims

1. A high-pressure injection nozzle device is provided on the side of a monitor connected to the tip of an injection rod, communicating with a hardening agent liquid supply pipe formed axially within the injection rod, A nozzle body comprising a hollow curing material liquid flow path consisting of a tapered intermediate inner diameter portion formed by the inner circumferential surface narrowing towards the tip, a tip inner diameter portion communicating with the tip of the intermediate inner diameter portion and having a diameter approximately the same as the tip of the intermediate inner diameter portion, and a rear end inner diameter portion communicating with the rear end of the intermediate inner diameter portion and having a diameter approximately the same as the rear end of the intermediate inner diameter portion, or a diameter that widens from approximately the same diameter towards the rear end, A hollow outer circumferential groove member is fitted to the tip of the nozzle body, has an outer circumferential surface that tapers in diameter toward the tip, has multiple inclined grooves formed on the outer circumferential surface that are obliquely inclined in substantially the same direction toward the tip, and has an air passage formed between its inner circumferential surface and the outer circumferential surface of the nozzle body, A projection is provided on the inner circumferential surface of the outer circumferential inclined groove member, which protrudes inward and contacts the outer circumferential surface of the nozzle body, It has an air cover in which a compressed air passage is formed between the inner surface and the outer surface of the outer inclined groove member, A high-pressure injection nozzle device characterized in that, by the projection on the inner surface of the outer circumferential groove member contacting the outer surface of the nozzle body, the outer circumferential groove member, which rotates in the circumferential direction of the outer surface of the nozzle body, is less likely to fluctuate, compressed air is injected from the compressed air injection port at the tip of the air passage between the inner surface of the outer circumferential groove member and the outer surface of the nozzle body, and as the outer circumferential groove member rotates, compressed air is injected from the tip between the inner surface of the air cover and the outer surface of the outer circumferential groove member, so that the area around the cement milk injection flow is covered by the compressed air injected from the compressed air injection port, and as the outer circumferential groove member rotates at high speed around the nozzle body, the compressed air is injected more strongly while swirling from the tip between the inner surface of the air cover and the outer surface of the outer circumferential groove member.

2. The high-pressure injection nozzle device according to claim 1, characterized in that the inclined grooves of the outer peripheral inclined groove member are formed on the outer peripheral surface of the outer peripheral inclined groove member in substantially the same shape and are provided in a range of 6 to 12.

3. The outer peripheral surface of the outer peripheral inclined groove member is provided, and the outer peripheral surface that protrudes outward and abuts against the inner peripheral surface of the air cover is formed in a curved shape, Since the curved outer peripheral surface is formed in a curved shape, when the outer peripheral inclined groove member rotates in the circumferential direction of the outer peripheral surface of the nozzle body, the contact area between the outer peripheral surface of the outer peripheral inclined groove member and the inner peripheral surface of the air cover is reduced, and the resistance force between the rotating outer peripheral surface of the outer peripheral inclined groove member and the inner peripheral surface of the air cover is reduced, the outer peripheral inclined groove member can be rotated at a higher speed in the circumferential direction of the outer peripheral surface of the nozzle body, and compressed air can be sprayed more strongly while swirling from the tip between the inner peripheral surface of the air cover and the outer peripheral surface of the outer peripheral inclined groove member, as described in claim 2.

4. The high-pressure injection nozzle device according to claim 2, characterized in that the inclined groove of the outer peripheral inclined groove member is obliquely inclined on the outer peripheral surface of the outer peripheral inclined groove member within a range of approximately 13.0 degrees to approximately 56.0 degrees toward the tip.

5. The inner diameter portion at the rear end of the nozzle body is formed with a flow path division portion that divides the hollow cross-section into multiple spaces. The high-pressure injection nozzle device according to claim 1, characterized in that the total cross-sectional area of ​​the flow channels divided at the flow channel division portion is 40% to 60% of the cross-sectional area of ​​the hollow cross-section of the inner diameter portion at the rear end near the flow channel division portion.

6. A ground improvement device equipped with the high-pressure injection nozzle device according to any one of claims 1 to 5, which is attached to the monitor.

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