JP2000291004A - Underground penetration auxiliary device for casing and underground penetration auxiliary method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a more rational underground penetration auxiliary device and a method thereof capable of greatly promoting penetration promotion efficiency without using any equipment having high efficiency or the like with a special specification by eliminating bad influence on the applicable ground. SOLUTION: An underground penetration auxiliary device includes a fluid supply device 19 used when a casing 9 is penetrated through a specific depth in the ground by means of an exclusive drive 11 and a supply pipe 26 providing an injection nozzle 27 to the lower end, the penetration of the casing 9 is promoted through the drive by jet force of fluid jetted in the ground from the fluid supply device, and the fluid supply device is constituted of a pair of compressed air supply device 16 and water supply device 17. It is equipped with a mixing ejector 20 connected to the compressed air supply device 16 and the water supply device 17. A drain outlet side of the mixing ejector 20 is connected to the supply pipe side 26, water led from the water supply device 17 is accompanied with compressed air led from the compressed air supply device 16, and it is capable of being sprayed in the ground from the injection nozzle 27.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for assisting or facilitating penetration of a casing such as various improved piles into the ground by a dedicated driving device when the casing is penetrated into the ground by a dedicated driving device. The present invention relates to an underground penetration assisting device and a penetration assisting method.

[0002]

2. Description of the Related Art A casing for forming sand piles or the like is usually lifted and lowered while being suspended by wires with a support leader of a base machine installed on the ground surface as a guide, and underground by a dedicated driving device. And then re-penetrated as needed. The casing has a hollow tube or a spiral blade attached to the outer periphery thereof, and a drilling blade may be attached to the lower end in some cases. As a dedicated driving device, for example, a rotating mechanism for rotating the casing forward or backward,
There is a vibration mechanism that penetrates the casing while applying vibration from above. In carrying out the construction work, the drive device to be used is selected together with the casings in accordance with the geological condition of the target ground and in consideration of construction efficiency and construction costs.

In the construction stage, for example, if a hard layer is present in the ground, the dedicated driving device may receive an excessive load and the penetration speed may decrease. In such a case, changing the driving device used or the casing itself affects the construction period and construction cost.Therefore, usually, a device for assisting penetration is used, and the ground on the tip side of the casing is excavated by the device, and It is intended to assist or facilitate the penetration of the casing by the drive. As this device configuration, either an air jet or a water jet is used. Specifically, the supply pipe is arranged to the lower end along the outer periphery of the casing, and a jet nozzle is attached to the lower end of the feed pipe, and air or water is supplied from the surface of the ground by a pump or the like through the feed pipe using a jet nozzle. From the ground to the ground at high pressure, and the jetting force excavates the ground on the tip side of the casing.

[0004]

In the conventional structure described above, if a high-capacity and high-capacity special pump or air compressor (compressor) is used in principle, the jetting power of water or the jetting power of air is used. As the strength is increased, the penetration assisting or promoting action can be increased. However, in general, general-purpose pumps (turbine pumps, axial flow pumps, mixed flow pumps, etc.) or compressors in civil engineering machines or compressors often fail to provide sufficient penetration assisting capability. In the case of water jet application using a water jet, a large amount of water (for example, 150 to 200 liters /
Minutes) is required. In addition, the applicable ground is generally soft ground to be improved, and it is not preferable that a large amount of water is discharged. Further, it is difficult to recover the water to be injected, so that it is desired to reduce the water as much as possible.

The present invention has been developed based on the above background. Its purpose is to use a specially designed equipment such as a high-performance device, greatly improve the penetration promotion efficiency, reduce the adverse effect on the applied ground, and realize a more rational underground penetration assistance device and penetration assistance method Is to do. Other objects will be clarified with the following description.

[0006]

In order to achieve the above object, an underground penetration assisting device according to the present invention is provided as illustrated in the drawings.
The casing 9 for piles and the like is connected to a dedicated driving device 11 on the ground side.
And a supply pipe 26 disposed along the outer surface of the casing 9 and having a jet nozzle 27 attached to a lower end thereof, and supplied by the fluid supply apparatus 19. The driving force of the driving device 11 assists or accelerates the penetration of the casing 9 by the ejection force of the fluid ejected from the ejection nozzle 27 into the ground through the pipe 26, and the fluid supply device 19 is provided with compressed air supply means. 16 and a water supply means 17 as a set, and first and second inlets 21a, 21a, which are connected to the compressed air supply means 16 and the water supply means 17, respectively.
A mixing ejector 20 having a second inlet 22a is connected to the outlet 21b side of the mixing ejector 20 to the supply pipe 26 side.
a through the compressed air supply means 16
From the injection nozzle 27 so as to be able to be sprayed into the ground in the form of a mist together with compressed air introduced through the first inlet 21a. The underground penetration assisting method of the present invention uses the underground penetration assisting device 15 described above when the casing 9 for stakes or the like is penetrated to a predetermined depth in the ground by the dedicated driving device 11 on the ground surface side. Injection nozzle 27
When the injection pressure is in the range of 6 to 10 kg / cm ² , the amount of the water introduced together with the compressed air is adjusted, and the water is injected from the injection nozzle 27 into the ground in a mist state.

[0007] The present invention as described above uses a general-purpose compressed air supply means (such as a compressor) and a water supply means (pump) in the same manner as the conventional apparatus configuration, that is, the apparatus utilizing the jetting force of water or the jetting force of air. Etc.) have been completed by finding that the degree of excavation of the ground can be improved several times by devising the used fluid and the injection form thereof. That is, the essential part of the present invention is that the fluid supply device 19 includes the compressed air supply means 16 and the water supply means 17 as a set, and the supply pipe 26 provided on the casing 9 side (directly or a pipe 29 such as a hose). The water introduced from the water supply means 17 into the mixing ejector 20 is connected to the discharge port 21b of the mixing ejector by connecting the discharging port 21b.
It is accompanied by compressed air introduced from the compressed air supply means 16 and is sprayed into the ground from the spray nozzle 27 in the form of a mist. The following operation and effect can be obtained.

First, the present invention provides a conventional water jet or
Ground excavation can be increased several times compared to the case of air injection.
This point is due to the fact that in the excavation test, in the setting example where the injection pressure is about 6 to 10 kg / cm ² similar to the conventional air injection (the discharge diameter of the injection nozzle is about 10 mm), the ground where the air was independently injected for 30 seconds was used. As a result of observing and comparing the excavation state (prior art) and the ground excavation state ((the present invention)) in which 5 to 30 liters / minute of water was sprayed for 30 seconds by the mixing ejector 20,
The mist injection can obtain about three times the excavating power as compared to the air injection alone, and a remarkable effect has been confirmed. The amount of water introduced is
This is a range in which mist-like injection is possible, but the value increases as the injection pressure of air increases. However, this amount of water is not a concept of utilizing the jetting power of the water itself, but is a very small amount of water, as compared with a water jet (usually 150 to 200 l / min) using a conventional water jet. Assuming the capability of a general-purpose air compressor (compressor), that is, an injection pressure of 6 to 10 kg / cm ² , it is to form a mist injection under a water introduction condition of 30 liter / min or less from a second viewpoint described later. . In addition, the excavation effect of such a mist spray is such that when high-speed air is accompanied by fine water molecules and collides with the ground in a mist state, it is larger than high-pressure injection with the air alone and collides with the ground. Generates energy.

Second, in the present invention, the amount of water used is significantly reduced as compared with the conventional water injection, so that the use of water is not bothered, and the possibility of adverse effects on the ground due to water addition can be eliminated. This means, for example, that a water jet using a conventional water jet is applied at a rate of 200 liters / min.
Even if the system is operated for only 0 minutes, 2000 liters of water is injected into the ground. Therefore, conventional water injection cannot ignore the effect on the ground, and is limited by the operating time when applied. The present invention can eliminate such a problem.

[0010] Third, the present invention is capable of excavating the ground without the risk of adversely affecting the ground due to water addition and realizing ground excavation several times better than conventional air injection. Not only to maintain the penetration speed normally by solving the problem, but also to make use of this positively to make the penetration speed higher, to select a simpler one as the dedicated driving device 11, and to reduce the driving cost, etc. It is easy to reduce or develop. This will be supplementarily described. Casing 9
The penetration speed is directly linked to the construction efficiency, and it is essential to penetrate the casing 9 at a higher speed in order to increase the construction efficiency.
The penetration speed is determined by the rotation mechanism (as described in Japanese Patent Application No. 7-197441, in which the casing is driven exclusively while rotating the casing), the vibration mechanism (Japanese Patent Application Laid-Open No. 48-37).
No. 906, etc.) and a rack and pinion mechanism (Japanese Unexamined Patent Application Publication No.
A configuration in which the rotary motion is converted into a linear motion and penetrated as described in 2005020, etc.) or a combination thereof, but in any case, if the penetration resistance received from the ground increases, the load on the dedicated driving device increases. And the speed gradually decreases. Therefore, as an example of development of the present invention, it is conceivable to always operate the present invention in construction design, increase the operation frequency, and set the penetration speed by the dedicated drive device 11 one step faster.

In the present invention, the mixing ejector 20 includes, for example, a substantially cylindrical main body 21 and a pipe 22 penetrating from the outer periphery of the main body 21 to the inside thereof. A first inlet 21a for introducing compressed air, and the other end side is formed as a discharge port 21b, and a second end for water introduction with a pipe end located in the main body of the pipe 22 facing the discharge port 21b. Entrance 2
2a. Further, as an example of the device structure, depending on whether the dedicated driving device 11 is mainly composed of the rotation mechanism, or mainly composed of the vibration mechanism or the rack and pinion mechanism, for example, in the latter non-rotation type, It is preferable that a plurality of the supply pipes 26, the injection nozzles 27, and the mixing ejectors 20 are used as a set because the casing 9 does not rotate. In this case, it is preferable that the compressed air supply means 16 and the water supply means 17 constituting the fluid supply device 19 are also used for the plurality of mixing ejectors 20. Furthermore, the installation location of the mixing ejector 20 may be, for example, the upper end side of the supply pipe 26 or the lower end side of the supply pipe 26, that is, close to the injection nozzle 27, in addition to the embodiment of the invention described below. You may make it. In the latter case, the dedicated pipe 24a on the side of the compressed air supply means 16 and the dedicated pipe 24b on the side of the water supply supply means 17 are both extended, and are respectively guided downward in the supply pipe 26 to correspond to the corresponding first pipes. To the second inlet 22a and the second inlet 22a.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be further described with reference to the accompanying drawings. FIG. 1 is an overall configuration diagram in which the present invention is applied to an apparatus used in a sand pile forming method.
3 schematically shows a mixing ejector section, and FIG. 3 schematically shows an injection nozzle section. That is, the construction machine for sand pile creation shown in FIG. 1 mainly includes a base machine 1, and a sand pile system is formed by a support leader 2, a back stay 3, a sheave block 4, an attachment 5, a moving bucket 6, and the like. Underground penetration assisting device 1 formed and applied with the present invention
5 is provided.

The base machine 1 can move back and forth and can turn, and is equipped with a winch drum 7, a compressed air compressor (not shown), an engine 8 used for the compressor, and the like. The support leader 2 is supported by two backstays 3. A movable bucket 6 is disposed on the side so as to be movable up and down, and sand or the like is appropriately charged. The back stay 3 is expanded and contracted by a hydraulic cylinder, and adjusts the tilt angle while supporting the leader 2. The sheave block 4 is paired with a pulley at the top of the leader 2, and is moved up and down by a wire from a winch drum 7 to vertically move an attachment 5 attached to a lower end. Attachment 5
Is mainly composed of a casing 9 and a sand hopper 10,
The casing 9 has a rotating mechanism 11 for rotating the casing 9 when it penetrates into or pulls out from the ground. The casing 9 is moved up and down by moving the rotating mechanism 11 along the reader 2. These are the same as before.

On the other hand, the underground penetration assisting device 15 assists or accelerates the penetration of the casing 9 into the ground by the rotating mechanism 11, and includes a compressed air supply means 16, a water supply means 17, and an engine 18 And a mixing ejector 20, a supply pipe 26 and an injection nozzle 27 on the casing 9 side, and a pipe 29 connecting the supply pipe 26 and the mixing ejector 20.
It has.

The fluid supply device 19 is mounted on a transport vehicle or the like and is movable. The fluid supply device 19 supplies electric power required by the compressed air supply means 16 and the water supply means 17. The compressed air supply means 16 includes a compressor 16a
And compressed air generated by driving the compressor 16a is stored in the receiver tank 16b. A pipe 23a is connected between the receiver tank 16b and the mixing ejector 20 (a first inlet 21a to be described later), and the compressed air in the receiver tank 16b is sent to the mixing ejector 20 by a valve operation (not shown). . Water supply means 17
Comprises a water storage tank 17a and a pump 17b, and the pump 17b and the mixing ejector 20 (a second inlet 22a described later) are connected by a pipe 23b. Then, the water in the water storage tank 17a is transferred to the mixing ejector 20 by driving the pump 17b.

As shown in FIG. 2, the mixing ejector 20 includes a main body 21 and a pipe 22 penetrating from the outer periphery to the inside of the main body 21. The main body 21 has a substantially cylindrical shape, one end of which is formed in a first inlet 21a for introducing air, and the other end of which is formed in a slightly narrowed outlet 21b.
The pipe 22 is penetratingly arranged with respect to the main body 21 so as to be integrated therewith. The penetrated insertion end side is the main body 21
And is bent toward the outlet 21c side to form a second inlet 22a facing the outlet 21c. The outwardly protruding portion 22 b is bent substantially parallel to the main body 21. And the first entrance 21
a is a pipe 2 between the outlet of the receiver tank 16b.
4a, and compressed air is introduced. The second inlet 22a has a pipe 24 between the second inlet 22a and the outlet of the pump 23a.
b and water is introduced. In FIG. 2, reference numeral 25a denotes a connector for connecting the corresponding end of the pipe 24a to the first inlet 21a, and reference numeral 25b denotes a second inlet 22a.
And a connecting tool 25b for connecting the corresponding end of the pipe 24b to the connecting piece 25b.

The supply pipe 26 is fixedly connected to the outer periphery of the casing 9 and extends along the vertical direction of the casing 9. The lower end reaches a little above the lower end of the casing 9 as shown in FIG. The injection nozzle 27 has an effective diameter of about 10 mm, and is provided with an on-off valve that is capable of injection when receiving a predetermined pressure. Then, the mounting-only bracket 2 is attached to the outer periphery of the casing 9.
8 and fixed downward. The upper end side of the supply pipe 26 is connected to a corresponding end of the pipe 29 via a dedicated connector. In FIG. 3, reference numeral 12 denotes an excavation blade fixed to a lower end of the casing 9. The excavating blade 12 is fixed to the lower end of the casing 9 by a bolt 13 or the like, and protrudes downward from the blade portion. Such a digging blade 12 is provided as needed.

Therefore, the above-described underground penetration assisting device 15
The other end 29a of the pipe 29 connected to the upper end side of the supply pipe 26 is connected to the discharge port 21b of the mixing ejector 20 by a connector 25c as shown in FIG.
Operationally, the water introduced through the pump 17b and the pipe 24b of the water supply means 17 and the second inlet 22a is supplied to the receiver tank 16b of the compressed air supply means 16.
And the compressed air introduced through the pipe 24a and the first inlet 21a is supplied to the pipe 29 from the discharge port 21b, and further, can be sprayed into the ground from the spray nozzle 27 through the supply pipe 26 from the spray nozzle 27. To In particular, in the above-described mixing ejector 20, since the second inlet 22a is located at the center of the main body 21, and is provided between the first inlet 21a and the outlet 21b, the second inlet 22a Water introduced from the first inlet 21a is put on the compressed air introduced from the first inlet 21a, and can be efficiently entrained to the outlet 21b and further to the pipe 29 side.

FIG. 4 schematically shows an example in which the above-described underground penetration assisting device 15 is applied to a sand pile forming method. In addition,
In the improved ground shown in the figure, the first soft layer 30 is weak in the depth direction.
It has been found to consist of a layer 30A and a somewhat harder second layer 30B. In this sand pile formation, the penetration speed is set to be higher than the conventional one based on the first layer 30A, and when the second layer 30B is penetrated, the underground penetration auxiliary device 15 is operated to set the penetration. It is designed to maintain speed. In FIG. 4, the above-described excavation blade 12 is omitted in the drawing. Reference numeral 31 denotes a sand mat laid on the ground surface.

FIG. 4A shows that the casing 9 has the rotating mechanism 11.
While initially rotating through the first layer 30A. The underground penetration assisting device 15 is operated immediately before the casing 9 penetrates the first layer 30A and reaches the second layer 30B. Then, on the distal end side of the casing 9, in addition to the excavating action of the excavating blade 12 as shown in FIG. He is breaking ground or digging. Since the casing 9 is rotated by the rotating mechanism 11, this excavating action is performed corresponding to the outer circumference of the casing 9, and the penetration resistance of the casing 9 is efficiently reduced. And, the underground penetration assisting device 15
As shown in (c), the casing 9 is stopped when it reaches the design depth that is the lower part of the second layer 30B. In general, sand is charged into the casing 9 at an appropriate time during the intrusion process or the like, and is pressurized before the end of the intrusion or immediately before the withdrawal. When the rotating mechanism 11 and the winch drum 7 are driven to pull out the casing 9 at a predetermined speed while rotating the casing 9, sand is discharged from the casing 9 as shown in FIG. 4 (d), and the columnar sand pile 32 is formed. Is done. In the above sand pile creation example, the pile creation procedure itself is performed as in the past,
The penetration speed of the casing 9 can be made several times faster than before by the operation of the underground penetration auxiliary device 15.

[0023]

As described above, according to the underground penetration assisting device and method of the present invention, the ground excavation can be increased several times as compared with the conventional water injection or air injection.
As compared with the conventional water injection, the amount of water used is significantly reduced, and the possibility of the water being adversely affected on the ground can be eliminated. Therefore, by utilizing this, it is possible to realize developments such as one-step high-speed penetration of the casing, selection of a simpler drive device as a dedicated drive device, and reduction of drive costs and the like.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of the entire configuration of a construction machine to which the present invention is applied.

FIG. 2 is a side view showing a mixing ejector unit of the underground penetration assisting device.

FIG. 3 is a schematic view showing an injection nozzle portion of the underground penetration assisting device.

FIG. 4 is a schematic diagram showing an example in which the method of the present invention is applied to a sand pile construction method.

[Explanation of symbols]

 1 is a base machine 9 is a casing 11 is a rotating mechanism (dedicated driving device) 15 is an underground penetration assisting device 16 is a compressed air supply means 17 is a water supply means 18 is a motor 19 is a fluid supply apparatus 20 is a mixing ejector 21a, 22a Is the first and second inlets 21b is the outlet 26 is the supply pipe 27 is the injection nozzle 29 is the pipe

Claims (2)

[Claims] 1. A fluid supply device for penetrating a pile or other casing to a predetermined depth in the ground by a dedicated driving device on the ground side, and an injection nozzle at a lower end disposed along the outer surface of the casing. A supply pipe, wherein the fluid supply device assists or accelerates the penetration of the casing by the driving device by the ejection force of the fluid ejected from the ejection nozzle into the ground through the supply tube by the fluid supply device, The fluid supply device is configured as a set of compressed air supply means and water supply means, and further includes a mixing ejector having first and second inlets connected to the compressed air supply means and the water supply means, A discharge port side of the mixing ejector is connected to the supply pipe side, and water introduced from the water supply means through the second inlet is supplied from the compressed air supply means to the water supply section. An underground penetration assisting device for a casing, wherein the device is capable of being sprayed into the ground from the spray nozzle in the form of a mist while being accompanied by compressed air introduced through a first inlet. 2. When the casing for forming a pile or the like is penetrated to a predetermined depth in the ground by a dedicated driving device on the ground surface side, the injection pressure of the injection nozzle is set to 6 to 1 by using the apparatus of claim 1.
An underground penetration assisting method for a casing, wherein the amount of water introduced into the compressed air is adjusted within a range of 0 kg / cm ² , and the water is sprayed from the spray nozzle into the ground in a mist state.