JP-2026074651-A - Ground improvement device and ground improvement method

JP2026074651AJP 2026074651 AJP2026074651 AJP 2026074651AJP-2026074651-A

Abstract

[Problem] To provide an improved ground improvement device and ground improvement method. [Solution] A ground improvement device according to one embodiment includes a rod inserted into the ground, a monitor provided on the rod, a first supply passage that passes through the inside of the rod and delivers liquid to the monitor, and a second supply passage that passes through the inside of the rod and delivers powder to the monitor. Furthermore, the monitor includes a mixing unit that generates a hardening material by mixing the liquid delivered by the first supply passage and the powder delivered by the second supply passage, and a hardening material nozzle that sprays the hardening material generated by the mixing unit into the ground. [Selection Diagram] Figure 2

Inventors

山本彰
佐藤潤
西田昂平

Assignees

日特建設株式会社

Dates

Publication Date: 20260507
Application Date: 20241021

Claims (8)

A ground improvement device for creating a ground improvement body, A rod inserted into the ground, A monitor provided on the aforementioned rod, A first supply path that passes through the inside of the rod and sends liquid to the monitor, A second supply path that passes through the inside of the rod and sends the powder to the monitor, Equipped with, The aforementioned monitor is A mixing unit that produces a hardening material by mixing the liquid supplied by the first supply channel and the powder supplied by the second supply channel, A hardening material nozzle for spraying the hardening material generated by the mixing unit into the ground, A ground improvement device equipped with [specific features/features].
The mixing section is The mixing chamber connected to the curing material nozzle and the second supply passage, A mixing nozzle connected to the first supply path and for injecting the liquid into the mixing chamber, Equipped with, As the liquid is sprayed by the mixing nozzle, the pressure in the mixing chamber is reduced, causing the powder in the second supply passage to be drawn into the mixing chamber and mixed with the liquid. The ground improvement device according to claim 1.
The mixing unit further comprises a pressure reduction chamber provided between the second supply passage and the mixing chamber, The powder in the second supply channel is drawn into the mixing chamber through the reduced pressure chamber. The ground improvement device according to claim 2.
The system further comprises a third supply path that passes through the inside of the rod and delivers gas to the monitor, The curing agent nozzle injects the gas supplied by the third supply path together with the curing agent. The ground improvement device according to claim 1.
The rod further comprises a fourth supply path that passes through the inside of the rod and delivers liquid to the monitor, The monitor further comprises a cutting nozzle that cuts the ground by injecting the liquid delivered by the fourth supply channel. The ground improvement device according to claim 1.
The system further comprises a fifth supply path that passes through the inside of the rod and sends gas to the monitor, The cutting nozzle injects the gas supplied by the fifth supply passage together with the liquid supplied by the fourth supply passage. The ground improvement device according to claim 5.
The aforementioned monitor is Located at the lower end in the extending direction of the rod, and having a discharge port from which the liquid of the first supply passage is discharged, A drilling tool provided around the discharge port, A valve unit that opens and closes the flow path from the first supply passage to the discharge port, It also has, The ground improvement device according to claim 1.
A ground improvement method using a ground improvement device according to any one of claims 1 to 7, Insert the rod into the ground, By rotating the rod while spraying the hardening material from the hardening material nozzle, and by pulling up the rod, a ground improvement body in which the hardening material has hardened is created in the ground. A ground improvement method that includes the following.

Description

This invention relates to a ground improvement device and a ground improvement method for improving the ground by creating a ground improvement body underground. Various conventional ground improvement methods exist, but one example is the high-pressure jet agitation method. In this method, a high-pressure jet is used to cut the ground, and a ground improvement body is created in the resulting space. The high-pressure jet used for cutting may be the hardening agent itself used to create the ground improvement body, or it may be a separate liquid such as water. The hardening agent is sprayed from a monitor at the tip of a rod inserted into the ground. The hardening agent is typically a cement slurry, a mixture of cement and water, which is delivered to the monitor through a channel within the rod. Japanese Patent Publication No. 2017-125397 Figure 1 shows an example of the configuration of a construction system for implementing the ground improvement method according to the first embodiment.Figure 2 is a schematic cross-sectional view showing the configuration of the monitor according to the first embodiment.Figure 3 shows an example of a ground improvement method using a ground improvement device or construction system according to the first embodiment.Figure 4 is a schematic cross-sectional view showing the configuration of the monitor according to the second embodiment.Figure 5 is a schematic cross-sectional view showing the configuration of the monitor according to the third embodiment.Figure 6 is a schematic cross-sectional view showing the configuration of the monitor according to the fourth embodiment.Figure 7 is a schematic cross-sectional view showing the configuration of the monitor according to the fifth embodiment.Figure 8 is a schematic cross-sectional view showing the configuration of the monitor according to the sixth embodiment.Figure 9 is a schematic cross-sectional view showing the configuration of the monitor according to the seventh embodiment. Several embodiments will be described with reference to the drawings. Each embodiment discloses an example of applying the ground improvement method and ground improvement apparatus according to the present invention to a high-pressure injection mixing method and an apparatus for implementing it. However, the configurations disclosed in each embodiment can be appropriately modified and applied to other types of ground improvement methods. [First Embodiment] Figure 1 shows an example of the configuration of a construction system for implementing the ground improvement method according to the first embodiment. This construction system comprises a ground improvement device 1, a pump 2, and a silo 3. The ground improvement device 1 comprises a rod 4 inserted into a hole H in the ground, a monitor 5 provided at the tip of the rod 4 (the lower end in the figure), and a work device 6 that holds the rod 4. The work device 6 includes a linear motion mechanism for moving the rod 4 up and down, and a rotation mechanism for rotating the rod 4. The work device 6 may further include a swinging mechanism for swinging the rod 4. Pump 2 supplies water from a water source S, such as a water tank, to the rear end 7 of rod 4. Silo 3 contains cement powder. This powder is supplied to the rear end 7 of rod 4. In the example shown in Figure 1, a storage section 8 is provided at the rear end 7 for temporarily storing the powder supplied from silo 3. Alternatively, the powder may be supplied directly to the rear end 7 without going through the storage section 8. The construction system may further include a powder supply device 9 for transporting the powder from silo 3 to storage section 8. The powder supply device 9 may, for example, be a belt conveyor, but is not limited to this example. As will be explained in more detail later, the water and powder supplied to rod 4 are sent through the inside of rod 4 to monitor 5, where they are mixed. The resulting hardening agent is then sprayed laterally from monitor 5 in the ground at high pressure. As the hardening agent sprayed into the ground hardens, a ground improvement body G is created. Figure 2 is a schematic cross-sectional view showing the configuration of the monitor 5 according to this embodiment. The monitor 5 comprises a first supply channel P1, a second supply channel P2, a mixing section 10, and a hardening agent nozzle 20. The first supply channel P1 and the second supply channel P2 extend through the inside of the rod 4 to the rear end 7. High-pressure water is supplied to the first supply channel P1 from the pump 2 to the rear end 7. Powder is supplied to the second supply channel P2 from the silo 3 to the storage section 8. The mixing unit 10 generates a hardening agent by mixing water supplied through the first supply channel P1 with powder supplied through the second supply channel P2. The hardening agent nozzle 20 sprays the hardening agent generated in the mixing unit 10. In this embodiment, the mixing uni