JPH09125864A - Shaft inner wall lining device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To construct a uniformly thick earth retaining lining layer on an excavated inner wall of a shaft smoothly and accurately and efficiently as well. SOLUTION: A shaft inner wall lining device is designed to line an excavated inner wall of a shaft which is substantially over-shaped in a cross section, with a cement-based earth retaining material. A material supply means 4 and a vertically-shaped drop pipe 3 are provided on the lower part of a material tank 2 which houses an earth retaining material hangingly supported in the shaft so that it may rise. A rotary shaft 21 provided with a plurality of agitation members 6 at the center line position of the drop pipe 3 where the agitation members 6 are projected in the radial direction so as to mix the earth retaining material with a set accelerating agent jetted from a nozzle 5. The lower end of this rotary shaft is connected to the central part of an impeller 7 which ejects the earth retaining material at the excavated inner wall of the shaft with a centrifugal force. The rotary shaft is turned, interlocking with the impeller 7. In addition to that, a vibrator 19 is laid out on a rubber board 18 provided to block a hole 17 bored in the side wall of the material tank.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shaft inner wall lining device for lining an inner wall of a shaft with a cement-based earth retaining material such as concrete.

[0002]

2. Description of the Related Art In the process of excavating a vertical shaft for constructing deep foundation piles and the like, the work of retaining earth on the inner wall at the stage of excavation to a predetermined depth and proceeding to excavation again is repeated. A steel member such as a liner plate is generally used for this soil retaining. On the other hand, in recent years, a so-called spraying method in which pressurized concrete is sprayed from a nozzle to form a concrete lining layer on an excavated wall surface may be adopted. According to this, there is an advantage that the pile can be formed in close contact with the excavated surface, so that the supporting force is increased, and that the pile can be constructed with an optimum diameter without being restricted by the specifications of the liner plate. Then, various vertical shaft inner wall lining devices that automate such a spraying method have been devised (Actual exploitation 62-16).
195, JP-A-5-263525 and JP-A-6-221082).

[0003]

However, in all of these prior arts, a single-cylinder spray nozzle is mounted on a pedestal so that it can rotate freely, and this single-cylinder spray nozzle is attached to the earth outside via a hose. It is connected to a continuous material supply device, and the earth retaining material is guided to a single-cylinder spraying nozzle by using compressed air as a medium and jetted.

Therefore, a single-direction nozzle locally sprays in a single direction, and in order to obtain a lining layer over the required range of the shaft inner wall, the single-cylinder nozzle is swung around and moved in the axial direction in a three-dimensional complex manner. Action is required.
Therefore, the lining thickness is partially insufficient or excessive, and it is difficult to smoothly and accurately form a lining layer having a uniform thickness.

Moreover, since compressed air is used as a spraying medium for the soil retaining material, the adherence to the wall surface becomes shocking, and dust and rebound are significantly generated. Therefore, the soil retaining material and the admixture material have a large loss, and it is difficult to perform efficient lining. In addition, it is difficult to monitor the spraying state due to dust remaining in the vertical shaft, etc., and it is difficult to actually automate it in combination with the complicated operation of the nozzle.

[0006] The present invention has been devised to solve such disadvantages of the prior art, and its main objects are as follows.
An object of the present invention is to provide a shaft inner wall lining device configured so that an earth retaining lining layer having a uniform thickness can be smoothly, accurately and efficiently applied to an excavated inner wall of a shaft.

[0007]

According to the present invention, such an object is a shaft inner wall lining device for lining a cement-based earth retaining material on an excavation inner wall of a shaft having a substantially circular cross section. A material tank that holds the earth retaining material in a fluid state, which is suspended so that it can be moved up and down, a drop cylinder provided at the bottom of the material tank, and the earth retaining material in the material tank is continuous in the drop cylinder. Material supply means to be introduced dynamically, a nozzle for continuously injecting a quick-setting agent to the earth retaining material introduced into the drop cylinder by the material supply means, and a drop in the drop cylinder with the quick-setting agent. Rotating mixing means for mixing the earth retaining material, and an impeller provided at the lower end of the dropping cylinder for centrifugally projecting the earth retaining material that is lowered from the falling cylinder and introduced into the center toward the excavated wall surface of the shaft. Has and
The rotary mixing means is composed of a rotary shaft arranged at the centerline position of the vertically-arranged cylindrical dropping cylinder and a plurality of stirring members radially protruding from the rotary shaft, and the lower end of the rotary shaft is It is achieved by providing a shaft inner wall lining device which is connected to a central portion of an impeller and rotates in conjunction with the impeller.

In particular, it is preferable that a plurality of the stirring members projecting to a position close to the inner surface of the dropping cylinder are arranged over a region from the injection position of the quick-setting agent to the impeller inlet below.

Moreover, it is preferable to arrange a vibrator in the material tank. Particularly, it is preferable that the vibrator is arranged on a rubber plate stretched so as to close a hole formed in the side wall of the material tank.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The structure of the present invention will be described in detail below with reference to the embodiments shown in the accompanying drawings.

FIG. 1 shows a schematic construction of a shaft inner wall lining device according to the present invention. This shaft inner wall lining device 1 forms a concrete lining layer for retaining soil on the inner wall surface of a shaft excavated in the construction of deep foundation piles. A material tank 2 for storing concrete and a lower part of the material tank 2 are provided. A screw rotor 4 for continuously feeding concrete into the dropping cylinder 3 provided in the above, a nozzle 5 for injecting a liquid quick-setting agent into the concrete fed by the screw rotor 4 into the dropping cylinder 3, and a quick connection A stirring rod 6 for shear-mixing the concrete into which the agent has been injected and descending in the falling cylinder 3, and an impeller 7 for centrifugally projecting the concrete introduced from the lower end of the falling cylinder 3 to the center.
And

The material tank 2 is composed of a body portion 8 composed of a straight cylindrical portion 8a and a funnel-shaped portion 8b below the body portion 8 and a top plate 9 covering the upper portion of the body portion 8 and made of a steel plate. They are integrated by welding and joining. The capacity of the material tank 2 is set so that the amount of concrete used in at least one lining work can be stored, and the work efficiency is improved.

The top plate 9 of the material tank 2 is provided with a concrete inlet 10, which is covered with a lid plate 11 which is hinged to the edge thereof. Further, a feeder driving motor 12 that rotationally drives the screw rotor 4 is mounted in a state of being covered by the hood 13. As shown in FIGS. 2 and 3, a pair of connecting tools 14 for suspending the entire main shaft inner wall lining apparatus 1 are fixed in the diametrical direction on the outer peripheral portion of the top plate 9. Arm part 15
The head portion 15b of the suspension member 15 to which a is connected is retained on a suspension line or the like so as to be suspended by a crane. A ring-shaped guard 16 is fixedly provided along the outer periphery of the upper end of the body portion 8 of the material tank 2.

The funnel-shaped portion 8b of the body portion 8 has a total of three holes 17 of the same triangular shape formed in each of the fan-shaped portions formed by dividing the funnel-shaped portion 8b in the circumferential direction. Hole 1
A rubber plate 18 is stretched on each of the parts so as to close the parts 7 tightly. At the center of the outer surface of the rubber plate 18, three vibrators (e.g., vibration motors) 19 are fixedly installed, and the rubber plate 18 excited by the vibrator 19 serves as a vibrating body. The concrete in the funnel-shaped portion 8b is smoothly and downwardly transferred. If necessary, the rubber plate 18 is reinforced with a metal wire or the like.

At the connecting portion between the funnel-shaped portion 8b of the body portion 8 and the falling barrel 3, the spiral blade-shaped screw blades 4a of the screw rotor 4 are arranged. The screw rotor 4 is arranged at the center line position of the body 8 of the material tank 2 and the cylindrical dropping cylinder 3 arranged concentrically with the body 8. The upper end of the shaft portion 4b of the screw rotor 4 is
The output shaft of a feeder driving motor 12 mounted on the top plate 9 of the material tank 2 is connected via a reduction mechanism. When the screw rotor 4 is normally rotated by the feeder driving motor 12, the concrete contained in the material tank 2 is continuously fed in a fixed amount, and when stopped or reversed, the concrete in the material tank 2 is dropped downward. Is prevented.

As such a quantitative supply means,
In addition to this, various feeder devices such as a rotary feeder can be applied, but there is a possibility that they may occur due to mixing of hardened concrete lumps remaining in the mixer or due to aggregate having a relatively large particle size. Such a screw type is suitable for preventing the clogging trouble.

A nozzle 5 for injecting a quick-setting agent is provided slightly below the portion of the falling tube 3 facing the lower end of the screw blade 4a.
However, three drop cylinders 3 are provided with the injection holes facing the center thereof and at equal intervals in the circumferential direction. This nozzle 5
Is configured to inject a mixture of a quick-setting agent and compressed air sent from a pump (not shown) and a compressor outside the mine via the conduit 20 toward the inside of the falling tube 3.

Screw blades 4 inside the falling tube 3
Below the a, a stirring rod 6 for mixing the concrete falling from the screw blades 4a and the quick-setting agent sprayed from the nozzle 5 toward the concrete is arranged at the center line position of the falling cylinder 3. A plurality of shafts (12 in total in FIG. 1) are arranged on the shaft portion 21. These stirring rods 6
Along the entire length of the shaft portion 21 from the injection position of the quick-setting admixture to the impeller 7 below, the shaft portion 21 is arranged at a predetermined interval in the axial direction in either the front, rear, left, or right radial direction.
The tip of the stirring rod 6 projects to a position close to the inner surface of the dropping cylinder 3 and has a function of scraping off concrete adhered to the inner surface of the dropping cylinder 3.

The shaft portion 21 is supported only by the dispersion portion body 22 at the center of the impeller 7 rotatably mounted on the lower end of the drop barrel 3, and is not connected to the screw rotor 4 above it. Therefore, the stirring rod 6 follows the impeller 7 rotated by the impeller driving motor 24 described later and is faster than the screw rotor 4 rotated by the feeder driving motor 12, for example, when the screw rotor 4 is rotating normally. While it is 150 rpm, the stirring rod 6 rotates at 750 rpm.

On the other hand, a pedestal 23 is fixed in the horizontal direction on the outer circumference of the dropping cylinder 3, and on this pedestal 23, one impeller driving motor 24 is mounted on one side of the dropping cylinder 3. The impeller drive motor 24 rotationally drives the cylinder shaft 27 of the impeller 7 via a drive pulley 25 connected to the output shaft on the lower surface side of the pedestal 23 and a V belt 26 attached to the drive pulley 25. ing. If necessary,
The impeller driving motor 24 may be configured to be capable of shifting and rotating in the reverse direction so that the rotation of the impeller 7 can be controlled appropriately. Drive pulley 25, V belt 26, and cylinder shaft 27
Is covered with a cover 28 in order to prevent the splash of concrete projected from the impeller 7 from adhering.

Further, as also shown in FIG.
In addition, the impeller driving motor 24 is supported by three leg members 29 vertically provided from a connecting portion between the cylindrical portion 8a and the funnel-shaped portion 8b of the material tank 2, and is protected by a protective plate 30 having a cylindrical shape as a whole. It is surrounded. A ring-shaped guard 31 is provided along the outer periphery at the lower end of the protective plate 30, and at the lower end portions of the leg members 28 and the guard 30, the shaft inner wall lining is placed when mounted on a pedestal outside the mine. The whole device 1 is supported.

In the impeller 7, a ring-shaped upper plate portion 32 having a circular hole into which the lower end of the falling cylinder 3 is fitted and a disc-shaped lower plate portion 33 arranged opposite thereto are connected to each other by a connecting member 34. Four blades 35 are arranged in a radial direction between the upper plate portion 32 and the lower plate portion 33. A cylinder shaft 27 externally fitted to the drop cylinder 3 is connected to the upper end of the connecting member 34, and is held so as to be rotatable relative to the drop cylinder 3. Further, at the center of the inner surface of the lower plate portion 33, a conical dispersion portion body 22 whose diameter is expanded downward is formed.
Is fixed and supports the lower end of the shaft portion 21 of the stirring rod 6.

Besides this, as shown in FIG. 3, the material tank 2
A power supply connection box 37, to which a cable 36 for supplying drive power to the feeder driving motor 12, the vibrator 19, and the impeller driving motor 24 is connected, is arranged on the top plate 9 of the above, and here, from the outside of the shaft to the inside of the shaft. Is connected to the power cable. Further, the conduit 20 for supplying the quick-setting agent to the nozzle 5 is connected by a coupling 38 to a liquid supply hose guided from the outside of the mine to the inside of the mine.

Here, the procedure for constructing the concrete lining by the shaft inner wall lining device 1 will be described.

First, before starting the lining,
Vertical shaft inner wall lining device 1 mounted on the installation platform outside the mine
Into the material tank 2 through the charging port 9 of 1., a required amount of concrete mixed with a predetermined water / Selund ratio and a slump value is charged. The concrete poured in here is prevented from falling by stopping or reversing the screw rotor 4.

When the vertical shaft is dug down to a predetermined depth through a series of excavation processes such as rock drilling and blasting to loosen the ground and carry the earth and sand out of the underground, the vertical shaft inner wall lining device 1 is vertically moved by a crane outside the shaft. It is suspended inside and lowered along the center line of the shaft to position it at the lining start position.
At this time, a translational actuator is connected to the suspension member 15 and then suspended by a mobile crane.

Then, the feeder drive motor 12 is normally rotated at a predetermined rotation speed and the vibrator 19 is operated by remote control by the drive control device outside the mine. Then, the concrete in the material tank 2 is smoothly transferred to the screw rotor 4, and then the screw rotor 4
Is continuously supplied to the dropping cylinder 3 at a speed proportional to the number of revolutions of the same.

The concrete sent by the screw blades 4a naturally falls from the lower end of the screw blades 4a in order without filling the inside of the dropping cylinder 3 formed with a relatively large diameter. At this time, after an appropriate amount of the quick-setting agent is continuously ejected from the nozzle 5, it is sheared and mixed by the stirring rod 6 rotating at a high speed while dropping the drop cylinder 3, and then the impeller 7 that is rotating is operated. It is thrown into the center.

Then, the concrete is the impeller 7
After being redirected in the direction orthogonal to the axis by the dispersion unit 22 at the central portion of the and dispersed in four directions, it is moved toward the outer periphery along the blades 35 by centrifugal force and discharged in a substantially tangential direction.
The concrete that is centrifugally projected in this way becomes small lumps and scatters over a wide area, collides with the inner wall surface of the shaft and spreads in a thin film, and these are deposited one after another and have a strong and uniform thickness on the entire peripheral surface of the shaft inner wall. A concrete lining layer having a thickness is formed.

As described above, the concrete is centrifugally projected, and at the same time, the above-mentioned translational actuator is expanded and contracted. Then, the shaft inner wall lining device 1 moves up and down along the center line of the shaft, and the impeller 7 can smoothly displace the projection position of the concrete onto the inner wall surface of the shaft. Therefore, the concrete lining layer having a uniform thickness in the depth direction can be formed smoothly and efficiently. At this time, a lining layer having a desired thickness is applied by appropriately controlling the number of times of expansion and contraction operation of the translational actuator, the rotation speed and rotation direction of the impeller driving motor 24, and the rotation speed of the feeder driving motor 12. be able to.

Further, the screw rotor 4 and the stirring rod 6
Are driven independently of each other, the stirring rod 6 and the impeller 7 can continue to rotate even if the screw rotor 4 is stopped and the supply of concrete to the dropping cylinder 3 is stopped. . On the other hand, since the falling cylinder 3 is not filled with concrete, when the screw rotor 4 is stopped, a small amount of concrete that is falling in the falling cylinder 3 is sufficiently mixed with the quick-setting agent by the stirring rod 6. Then, centrifugal projection is promptly carried out from the impeller 7. For this reason,
In combination with the wiping action due to the large number of stirring rods 6 rotating at high speed in the falling barrel 3, concrete can be prevented from remaining on the falling barrel 3 and the impeller 7.

Although the round rod-shaped stirring rod 6 is used as the stirring member of the rotary mixing means in the present embodiment, the stirring member in the present invention is not limited to such a shape, and may be, for example, a plate-shaped member. It may be one.

[0033]

As described above, according to the present invention, the earth retaining material is sheared and mixed by the plurality of stirring members radially protruding from the rotation shaft arranged at the center line position of the vertically-arranged dropping cylinder. In addition, the drop cylinder is formed to have a relatively large diameter so that the earth retaining material will fall naturally without filling the inside of the drop cylinder. Then, the earth retaining material is evenly distributed in the circumferential direction while being radially outwardly moved by centrifugal force in the process of falling in the falling cylinder, and is introduced into the central portion of the impeller. Therefore, the soil retaining material is evenly projected from the impeller in the circumferential direction of the inner wall of the excavation, so that the lining layer having a uniform thickness over the entire circumference can be efficiently obtained.

In addition, if the lower end of the rotating shaft of the stirring member is connected to the center of the impeller so that the stirring member rotates at high speed in conjunction with the impeller, the earth retaining material and the quick-setting admixture can be rapidly added. Since they can be mixed, they are extremely effective in obtaining a strong lining layer.

Further, since the earth retaining material that naturally falls in a state where the falling cylinder is not filled is shear-mixed, a predetermined high speed rotation of the rotary mixing means can be realized with a small power, and the stirring member Wear is significantly suppressed. Moreover,
When the supply of soil retaining material from the material supply means is stopped, the soil retaining material in the falling cylinder is immediately projected and discharged from the impeller, so that the soil retaining material containing the quick-setting agent remains and solidifies in the falling cylinder. It is possible to obtain an advantage that the binding can be suppressed.

In particular, when a large number of stirring members projecting to the position close to the inner surface of the drop cylinder are arranged from the injection position of the quick-setting agent to the impeller inlet below, the earth retaining material attached to the inner surface of the drop cylinder is removed. By the wiping action of stripping off, it is possible to significantly suppress the clogging of the earth retaining material on the inner surface of the falling cylinder. In addition, many stirring members have a function of suppressing the free fall of the soil retaining material, and the staying time in the dropping cylinder is prolonged, and the stirring effect can be enhanced.

Further, when the material tank is provided with a vibrator, the earth retaining material in the material tank is sequentially and smoothly transferred to the material supply means by the vibration of the vibrator. Therefore, the soil retaining material can be constantly introduced into the material supplying means, and the supply amount from the material supplying means to the falling cylinder, that is, the projection amount from the impeller can be kept constant. Therefore, there is an extremely large effect in making the lining layer thickness more uniform.

Particularly, when the vibrator is arranged on the rubber plate stretched so as to close the hole formed in the material tank, the amplitude is expanded as compared with the case where the vibrator is directly arranged on the steel plate material tank having high rigidity. However, the feeding performance can be greatly improved, and a stable supply can be achieved without being affected by the difference in the properties of the soil retaining material such as the slump value, the viscosity, and the composition. Moreover, there is an advantage that noise can be significantly reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a shaft inner wall lining device configured according to the present invention.

FIG. 2 is a side view of the shaft inner wall lining device shown in FIG.

FIG. 3 is a top view of the shaft inner wall lining device shown in FIG. 1.

[Explanation of symbols]

 1 Vertical shaft inner wall lining device 2 Material tank 3 Dropping cylinder 4 Screw rotor 4a Screw blade 4b Shaft part 5 Nozzle 6 Stirring rod 7 Impeller 8 Body part 8a Cylindrical part 8b Funnel part 9 Top plate 10 Input port 11 Lid plate 12 Feeder drive Motor 13 hood 14 connector 15 suspension member 15a arm 15b head 16 guard 17 hole 18 rubber plate 19 vibrator 20 conduit 21 shaft 22 dispersion unit 23 frame 24 impeller drive motor 25 drive pulley 26 V belt 27 cylinder shaft 28 cover 29 leg member 30 protective plate 31 guard 32 upper plate part 33 lower plate part 34 connecting member 35 blade part 36 cable 37 power connection box 38 coupling

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuo Ugada 4-1, Egasaki-cho, Tsurumi-ku, Yokohama-shi, Kanagawa Electric Power Technology Laboratory, TEPCO (72) Inventor Sakae Nakai 518 Komagaki, Nagareyama-shi, Chiba No. 1 Mitsui Construction Co., Ltd. Technical Research Institute (72) Inventor Masataka Uozumi 518 No. 1 Komagaki, Nagareyama City, Chiba Prefecture Mitsui Construction Co., Ltd. Technical Research Institute (72) Tatsuo Ito No. 518 Komagaki, Nagareyama City, Chiba Mitsui Construction Technical Research Institute Co., Ltd.

Claims (4)

[Claims] 1. A shaft inner wall lining device for lining a cement-based earth retaining material on an excavated inner wall of a shaft having a substantially circular cross-section, the earth retaining material being suspended in a vertical direction and being suspended in a fluid state. A material tank for accommodating, a drop cylinder provided under the material tank, a material supply means for continuously introducing the earth retaining material in the material tank into the drop cylinder, and the fall by the material supply means. A nozzle for continuously injecting a quick-setting agent into the soil retaining material introduced into the cylinder, a rotary mixing means for mixing the soil retaining material falling in the dropping cylinder with the quick-setting agent, and a dropping cylinder And an impeller provided at the lower end for centrifugally projecting the earth retaining material, which descends from the falling cylinder and is introduced into the central portion, toward the excavation wall surface of the vertical shaft, and the rotary mixing means has a vertical cylindrical shape. Placed at the center line position of the drop cylinder A rotating shaft and a plurality of stirring members radially protruding from the rotating shaft, the lower end of the rotating shaft is connected to the center of the impeller, and rotates in conjunction with the impeller. Vertical shaft inner wall lining device. 2. A plurality of the stirring members projecting up to a position close to the inner surface of the dropping cylinder are arranged over a region from the injection position of the quick-setting agent to the impeller inlet below. The shaft inner wall lining device according to claim 1. 3. The shaft inner wall lining device according to claim 1, wherein a vibrator is arranged in the material tank. 4. The shaft inner wall lining device according to claim 3, wherein the vibrator is arranged on a rubber plate stretched so as to close a hole formed in a side wall of the material tank. .