JPH01244013A - Method for increasing density of particle group region - Google Patents

Abstract

PURPOSE: To density a particle group area by inserting a probe having an air motor into the particle group area soaked in water, and sucking water in the particle group area while imparting vibrational force. CONSTITUTION: A probe 10 having a weight 18 rotating by an air motor 26 is replaced with a drill or an auger of an excavator to be press fitted in a particle group area. While generating vibration by rotation of the weight 18, pore water is sucked from a well screen 36 by a rising flow of air rising in a third conduit 34 delivered from the motor 26.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention applies vibration force to a particulate mass immersed (or submerged) in water to forcibly remove water from the particulate mass. In particular, it relates to a method for densifying or compressing the particle population region.

BACKGROUND OF THE INVENTION Vibratory densification probes have traditionally been used to consolidate particle swarm regions before structures are placed over them. If the particle swarm region is not solidified in advance, the subsequent subsidence of the particle swarm region or liquefaction under the structure will cause damage to the structure,
Or it may endanger the safety of people or objects in or near the structure. Densification probes in the prior art consist of an elongated conduit that is pushed into the swarm region and a motor arrangement for causing vibrations in the probe within the swarm region, thereby solidifying or “densifying” the swarm region. It is a relatively simple device that increases density.

Since pore water with pressure exists in a confined state in the gaps between the individual particles constituting the particle group region,
Conventional densification probes are believed to consume large amounts of energy. More specifically, pore water with pressure in the area surrounding a conventional densification probe is
It is believed that a significant amount of the energy generated by the vibrations of the probe is absorbed and that this absorbed energy does not contribute to the desired densification of the particle swarm region. In contrast, the vibrational energy produced by conventional probes tends to increase the pressure of the trapped pore water, which flows upwardly through the densified region, thereby causing the pore water to flow upwardly through the densified region. Water escapes from the area. Such a flow of interstitial water tends to relax (de-densify) the particle group region rather than densify it.

The inventor describes “Method and Apparatus for Building Underwater Embankments”.
Constructing an Underwa
U.S. Patent No. 4 filed under the name
As disclosed in US Pat. No. 6,664,557, when new fill material is added to a fill pile, the introduction of water into the fill pile material increases the The density of the particle swarm region may increase significantly. The reason is that when a slope is formed, the water flowing to the side of the accumulating embankment pile tends to support the slope of the pile, resulting in a steeper and more densely packed slope. The purpose is to enable pile structure.

It is believed that similar principles can be applied to significantly improve the method of densification of particle swarm regions. in this case,
The particle swarm region may be in or out of water, but may be immersed (or submerged) in pore water with pressure.
state. This not only applies a vibrational force to the swarm region, but also extracts water from the region surrounding the vibrating probe, relieving the pressure of the pore water and inhibiting the upward flow of pore water through the swarm region. (as a result of preventing loosening of the particle swarm region), it is possible to reduce the amount of energy absorbed and consumed by interstitial water and increase the amount of energy utilized to consolidate the particle swarm region. This is achieved by using high-density probes.

The interstitial water is forced toward the probe, and the flow acts to pull the particles toward the probe rather than away from the probe, thereby causing compaction (i.e., densification) of the particle population region. Facilitate. As the particles consolidate closer together, the interstitial water trapped between the particles must be released and reach the surface before the particles can stabilize within a smaller volume. Under normal conditions (i.e., conventional technology), a significant amount of time
Required for released water to reach the surface. By forcing out the trapped pore water, the present invention facilitates extremely rapid densification of the particle population region.

Neither the inventor's US patents mentioned above nor the prior art take into account the improved densification reservoir technology described below.

SUMMARY OF THE INVENTION The present invention provides a method for densifying an immersed particle population region. A densification force is applied to the swarm region while controlling the dispersion of water from within the swarm region to prevent water dispersion away from the source of the force. Water is forced out (i.e., water is sucked out) from the particle swarm region to the source of force.
.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

1 to 3 show densification probes for carrying out the method of the present invention.
An example of e) is shown below. The probe (10) is in the form of an extending tube with a pointed end (12) at one end. The tip (12) serves to push the probe (10) into the particulate mass that is to be consolidated or "densified". The pointed end (1
2) can be replaced by a drill tip or auger so that the probe can be screwed into the ground through rarely dense or hard soil layers. It should be noted that conventional probes cannot be handled in the above manner because their power supply cables and structures to enable global deployment interfere. By contrast, the probe (10) can be placed in cooperation with a drilling rig that can rotate it at will. Typically, the mold opening of the probe (10) is sufficiently polymerized for the probe (10) to penetrate into the ground (as explained below). vibrated to generate power), the drilling rig is used to push or screw the probe (1o) into the ground. The tubular casing (14) has a cylindrical cavity (16) accommodating the eccentric weight (18) therein.
). The weight (18) is rotatably supported by bearings (20) and (22) attached to both ends thereof. Second tubular casing (2
4) forms another cylindrical cavity for housing the air motor (26).

The air motor (26) operates as follows:
The weight (18) is drivingly coupled to rotate the weight (18) about the longitudinal axis of the probe (10), thereby generating a force that causes the probe (10) to vibrate.

The third tubular casing (28) has a first conduit section (30
), another cylindrical cavity having a second conduit section (32) and a third conduit section (34). The well screen (veil 5screen) (36) allows water to flow from the area surrounding the probe (10) to the first conduit section (3).
The probe (10) is disposed in a cylindrical portion of the outer peripheral surface of the tubular casing so that the probe (10) flows into the probe (10) and is then taken out from the probe (10). The relative placement of the well screen (36) is not critical. For example, the probe (1o) may be configured to position the well screen (36) around or below the motor (26) rather than above the motor (26) as shown. The structure may be changed.

The motor (26) is preferably supplied with pressurized air from an external compressed air source (not shown). The compressed air is
As shown at 38), it is sent to the motor (26) via the second conduit section (32) and the tubular casing (24). The air enters the tubular casing (24) as indicated by the arrow (4o).

(28) through the motor (26) and then through the third conduit section (34) and finally out of the probe (10). The first conduit section (30) is connected to the third conduit section (30) at the position indicated by (42).
4). Air discharged from the motor (26) and passing through the third conduit section (34) rapidly passes through the location (42), thereby causing air to flow into the first conduit section (30) near the interior surface of the well screen (36). , a low pressure area occurs. Accordingly, pore water in the area surrounding the probe (10) passes through the second conduit section (36) and the first conduit section (30), through the position (42), and through the third conduit section (34). ). The interstitial water thus passes through the third conduit section (34) together with the air discharged from the motor (26) and is removed from the probe (10).

The probe (10) configured as described above is used in the following manner.

First, the probe (10) is hardened or "dense"
A tip (12) is placed pointing towards the surface of the particle swarm region to be treated. The particle population region will be immersed or nearly immersed in pore water under pressure. For example, the particle group region may be partially or completely submerged in water or may exist below the groundwater table.

The probe (10) is usually arranged perpendicular to the surface of the particle swarm region, but in some cases (for example to increase the density of the slope of a submerged embankment pile) It is arranged at an angle.

Compressed air is sent to the air motor (26) in the manner described above in order to rotate the eccentric weight (18), which generates vibrations in the probe (10) and, based on the action of the vibrations, said particle cluster region. advance to the desired depth. During the initial embedding of the probe (10) in the particle swarm region, the compressed air is forced through the well screen (36) by closing the air/water outlet at the top end of the probe (10). the probe (10)
Loosen the granular material surrounding the probe (10
) can be easily buried underground. Initial probe implantation is also carried out by attaching an air or water jet to the tip (12) of the probe (10) to facilitate particle movement upon implantation of the probe (10) into the particle swarm region. It can be done easily. - degree, probe (10
) reaches the desired depth, the air/water outlet at the upper end of the probe (10) is unblocked and the air motor (26) continues to operate. In this way,
Air and water are exhausted from the probe (10) via the third conduit section (34) until the particle swarm region is sufficiently densified.

The present invention has at least two important advantages over the prior art. First, the prior art has been known to reduce sloped surfaces (i.e., tailings dams).
It is not possible to densify a region of particles submerged in water or the like. This is because the vibration in the above conventional technology is
This is because there is a tendency for the particle group region to become liquid, resulting in failure on the inclined surface. In contrast to this,
The present invention solidifies and stabilizes the inclined surface while densifying the particle group region. Second, conventional probes are usually large and bulky devices that require heavy cranes and large amounts of power to be supplied for operation. However, the probe (10) for practicing the present invention can be of short length (i.e., about 152.4 cm; about 5 feet) so that it can be easily manipulated by hand and requires less overhead space. It can also be operated in restricted areas. A further feature to be made clear is that the probe is constructed according to the invention and that said probe driven by a 10 horse cam motor achieves the same performance as a conventional probe driven by a 100 horse cam motor. .

The invention includes many variations and modifications.

For example, the first example of the above embodiment. The second and third conduit portions surround each other (i.e. the first conduit portion (30) surrounds the second conduit portion (30).
and a third conduit section (32).

(34); third conduit portion (34) surrounding second conduit portion (32)), the air passes rapidly through location (42). Sometimes, a third
Only the first conduit section (30) may be arranged outside the conduit section (34).

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway cross-sectional view of an example of a high-density probe for carrying out the method of the present invention, FIG. 2 is a cross-sectional view taken along line 2-2 in FIG. 1, and FIG. 2 is a sectional view taken along line 3-3 in FIG. 1. FIG. (10)...High density probe (12)...
... Pointed end (14) ... Tubular casing (16) ... Cylindrical cavity (18) ...
...Eccentric weight (20), (22) ...Bearing (24)
)...Second tubular casing (26)...
...Air motor (28)...Third tubular casing (30)...
...First conduit section (32)...Second conduit section (34)...Third conduit section (36)...Well screen (42)・・・
... Air rapid passage position (above)

Claims (1)

[Claims] [1] A method for increasing the density of a particle group region immersed in water, comprising: (a) applying a force necessary to compact the particle group region to the particle group region; and (b) forcibly sucking water from the region toward the source of the force while applying the force. [2] A method for increasing the density of a particle group region immersed in water, comprising: (a) applying a force necessary to compact the particle group region to the particle group region; and (b) the step of: a particle swarm region comprising the step of providing a region of low pressure within the particle swarm region to prevent water dispersion away from the source of the force during the application of the force. Densification method. [3] A method for increasing the density of a particle group region immersed in water, the method comprising: (a) applying a force necessary to compact the particle group region to the particle group region; and (b) the step of: A method for densifying a particle population region, comprising the step of pumping water from the region toward the source of the force during the application of a force. [4] The method for densifying a particle group region according to claim 2, characterized in that water is forcibly sucked from the region toward the source of the force.