JP2965495B2 - Vertical shaft inner wall lining device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art In the process of excavating a shaft for constructing a deep foundation pile or the like, an operation of excavating to a predetermined depth, applying earth retaining to an inner wall, and proceeding with excavation again is repeatedly performed to a target depth. Generally, a steel member such as a liner plate is used for the earth 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 excavation wall surface, is sometimes used. According to this, there is an advantage that the pile can be formed in close contact with the excavation surface, so that the supporting force increases, and that the pile can be constructed to the optimum diameter without being restricted by the standard of the liner plate. Various types of vertical shaft inner wall lining devices that automate such a spraying method have been proposed (Japanese Utility Model Laid-Open No. 62-16).
195, JP-A-5-263525 and JP-A-6-221082).

[0003]

However, in each of these prior arts, a single-cylinder spray nozzle is mounted on a gantry so as to be swivelable, and the single-cylinder spray nozzle is connected to a soil retaining hole outside a mine via a hose. The earth retaining material is connected to a continuous material supply apparatus, and the earth retaining material is guided to a single cylinder spray nozzle using compressed air as a medium and injected.

[0004] Therefore, in order to obtain a lining layer over a required range of the inner wall of the shaft, a single-dimensional nozzle sprays the nozzle and moves it in the axial direction in order to obtain a lining layer over a required range of the inner wall of the shaft. Operation is required.
For this reason, the lining thickness is partially insufficient or excessive, making it difficult to form a lining layer having a uniform thickness smoothly and accurately.

[0005] In addition, since compressed air is used as a spraying medium of the earth retaining material, the adhesion to the wall surface is shocking, and dust and rebound are remarkably generated. For this reason, the loss of the earth retaining material and the admixture material was large, and it was difficult to perform efficient lining. In addition, it is difficult to monitor the spraying state due to the accumulation of dust in the shaft, etc., and it has been difficult to automate in practice 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 a soil retaining lining layer having a uniform thickness can be smoothly, accurately, and efficiently installed on an excavation inner wall of a shaft.

[0007]

SUMMARY OF THE INVENTION According to the present invention, there is provided a vertical shaft inner wall lining apparatus for lining an excavation inner wall of a shaft having a substantially circular cross section with a cement-based earth retaining material. A material tank which is suspended so as to be able to ascend and descend and stores the earth retaining material in a flowing state, a drop cylinder provided at a lower portion of the material tank, and the earth retaining material in the material tank is continuously arranged in the fall cylinder. A material supply means for continuously introducing, a nozzle for continuously injecting a quick-setting agent to the earth retaining material introduced into the dropping cylinder by the material supplying means, and dropping in the dropping cylinder with the quick-setting agent A rotary mixing means for mixing the earth retaining material to be removed, and an impeller provided at the lower end of the dropping cylinder, for centrifugally projecting the earth retaining material descending from the dropping cylinder and introduced into the center toward the excavation wall surface of the shaft. And
The rotation mixing means includes a rotation shaft arranged at the center line position of the vertically-placed cylindrical dropping cylinder, and a plurality of stirring members radially protruding from the rotation shaft, and a lower end of the rotation shaft is This is achieved by providing a shaft inner wall lining device that is connected to a center portion of an impeller and rotates in conjunction with the impeller.

[0008] In particular, it is preferable that a plurality of the stirring members projecting to a position close to the inner surface of the drop cylinder are provided over a region from a quick-setting agent injection position to a lower part of the impeller inlet.

In addition, it is preferable to provide a vibrator in the material tank. In particular, it is preferable that the vibrator is disposed on a rubber plate stretched so as to close a hole formed in a side wall of the material tank.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the present invention will be described in detail below based on embodiments shown in the accompanying drawings.

FIG. 1 shows a schematic structure of a shaft inner wall lining device according to the present invention. The vertical shaft inner wall lining device 1 forms a concrete lining layer for retaining a ground on the inner wall surface of a shaft excavated in the construction of a deep foundation pile, and includes a material tank 2 for storing concrete and a lower portion of the material tank 2. A screw rotor 4 for continuously feeding the concrete into the drop cylinder 3 provided in the nozzle; a nozzle 5 for jetting and injecting a liquid quick-setting agent into the concrete fed into the drop cylinder 3 by the screw rotor 4; A stirring rod 6 for shear-mixing the concrete in which the agent is injected and descending in the falling cylinder 3, and an impeller 7 for centrifugally projecting the concrete introduced into the center from the lower end of the falling cylinder 3.
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 that covers the upper portion of the body portion 8. They are integrated by welding or the like. The capacity of the material tank 2 is set so as to store an amount of concrete used in at least one lining operation, thereby improving the efficiency of the operation.

The top plate 9 of the material tank 2 is provided with an opening 10 for concrete, which is covered with a lid plate 11 hinged to the edge. Further, a feeder driving motor 12 for rotating and driving the screw rotor 4 is mounted in a state covered by a hood 13. As shown in FIGS. 2 and 3, a pair of connecting members 14 for suspending the entire inner shaft lining device 1 of the shaft are fixedly provided in a diameter direction on the outer peripheral portion of the top plate 9. Arm 15
The head 15b of the hanging member 15 to which a is connected is hung by a crane, for example, by fixing it to a hanging line. A ring-shaped guard 16 is fixedly provided at the upper end of the body 8 of the material tank 2 along the outer periphery.

The funnel-shaped portion 8b of the body 8 has three identical triangular holes 17 formed in each of the fan-shaped portions obtained by dividing the funnel-shaped portion into three in the circumferential direction. Hole 1
Each of the rubber plates 18 is stretched so as to tightly close the 7. At the center of the outer surface of the rubber plate 18, three vibrators (for example, vibration motors) 19 are fixedly provided, one each, and the rubber plate 18 excited by the vibrator 19 serves as a vibrator. The concrete in the funnel-shaped portion 8b is successively and smoothly transferred downward. If necessary, a rubber plate 18 reinforced with a metal wire or the like is used.

A helical band-shaped screw blade 4a of the screw rotor 4 is disposed at a connecting portion between the funnel-shaped portion 8b of the body portion 8 and the drop cylinder 3. The screw rotor 4 is disposed at the center line position of the body 8 of the material tank 2 and the cylindrical drop cylinder 3 arranged concentrically with the body 8. The upper end of the shaft portion 4b of the screw rotor 4 is
An output shaft of a feeder driving motor 12 mounted on the top plate 9 of the material tank 2 is connected via a speed reduction mechanism. When the screw rotor 4 is rotated forward by the feeder driving motor 12, the concrete contained in the material tank 2 is continuously fed out by a fixed amount, and when stopped or reversed, the concrete in the material tank 2 falls downward. Is prevented.

[0016] Such a quantitative supply means includes:
In addition to this, various feeder devices such as a rotary feeder can be applied. However, there is a possibility that the hardened concrete mass remains in the mixer and is mixed in or the aggregate has a relatively large particle size. In order to prevent blockage trouble, such a screw type is preferable.

Slightly below the drop cylinder 3 which faces the lower end of the screw blade 4a, a nozzle 5 for injecting a quick-setting agent is provided.
Are provided at equal intervals in the circumferential direction with the injection holes facing the center of the drop cylinder 3. This nozzle 5
Is designed 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 a conduit 20 toward the inside of the drop cylinder 3.

Screw blade 4 inside drop cylinder 3
Below the a, a stirring rod 6 for mixing the concrete dropped from the screw blade 4a and the quick-setting agent injected from the nozzle 5 toward the concrete is arranged at the center line position of the drop cylinder 3. A plurality of shafts 21 (a total of 12 shafts in FIG. 1) are arranged. These stirring rods 6
Along the entire length of the shaft portion 21 from the quick-setting agent injection position to the lower impeller 7, the shaft portion 21 is disposed in any of the front, rear, left, and right radial directions at a predetermined interval in the axial direction.
The tip of the stirring rod 6 protrudes to a position close to the inner surface of the drop cylinder 3, and has a function of scraping concrete adhered to the inner surface of the drop cylinder 3.

The shaft portion 21 is supported only by the dispersion portion 22 at the center of the impeller 7 rotatably mounted at the lower end of the drop cylinder 3, and is not connected to the screw rotor 4 above it. For this reason, the stirring rod 6 follows the impeller 7 rotated by the impeller driving motor 24, which will be described later, and operates at a higher speed than the screw rotor 4 rotated by the feeder driving motor 12, for example, when the screw rotor 4 rotates forward. Is 150 rpm, whereas the stirring rod 6 rotates at 750 rpm.

On the other hand, a gantry 23 is fixed on the outer periphery of the drop cylinder 3 in a horizontal direction, and one impeller driving motor 24 is mounted on one side of the drop cylinder 3 on the gantry 23. The impeller driving motor 24 rotationally drives the cylindrical shaft 27 of the impeller 7 via a driving pulley 25 connected to an output shaft on the lower surface side of the gantry 23 and a V-belt 26 attached to the driving pulley 25. ing. If necessary,
The impeller driving motor 24 may be configured to be capable of shifting and reversing, so that the rotation of the impeller 7 can be appropriately controlled. Drive pulley 25, V-belt 26 and cylindrical shaft 27
Is covered by a cover 28 in order to prevent the concrete splashing from the impeller 7 from adhering.

Also, as shown in FIG.
Further, the impeller driving motor 24 is supported by three leg members 29 which are suspended from a connection portion between the cylindrical portion 8a and the funnel-shaped portion 8b of the material tank 2, and is formed by a protective plate 30 having a cylindrical shape as a whole. It is surrounded. A ring-shaped guard 31 is provided at the lower end of the protective plate 30 along the outer periphery. The leg member 28 and the lower end portion of the guard 30 are used to mount the inner wall lining of the shaft when mounting on a stand outside the mine. The entire device 1 is supported.

The impeller 7 has a ring-shaped upper plate portion 32 having a circular hole into which the lower end of the drop cylinder 3 is fitted, and a disk-shaped lower plate portion 33 opposed to the ring-shaped upper plate portion 33. A total of four blades 35 are arranged between the upper plate 32 and the lower plate 33 in the radial direction. The upper end of the connecting member 34 is connected to a cylindrical shaft 27 which is fitted to the falling tube 3 and is held so as to be rotatable relative to the falling tube 3. In the center of the inner surface of the lower plate portion 33, the conical dispersion member 22 having a diameter increased downward is provided.
Is fixed, and supports the lower end of the shaft portion 21 of the stirring rod 6.

In addition, as shown in FIG.
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 provided on the top plate 9, and here, from outside the pit to inside the pit The power cable led to is connected. Further, a conduit 20 for supplying the quick-setting agent to the nozzle 5 is connected to a liquid feed hose led from the outside of the pit to the inside of the pit by a coupling 38.

Here, a concrete lining construction procedure using the shaft inner wall lining device 1 will be described.

First, prior to starting the lining,
Vertical shaft inner wall lining device 1 received on a mounting stand outside the mine
A required amount of concrete mixed with a predetermined water / Selund ratio and a slump value is charged into the material tank 2 from the charging port 9 of (1). The concrete poured here is prevented from falling by stopping or reversing the screw rotor 4.

When the shaft is dug down to a predetermined depth through a series of excavation processes such as loosening the ground by a rock drill or blasting and carrying out the earth and sand outside the shaft, the shaft inner wall lining device 1 is erected by a crane outside the shaft. And lowered along the centerline of the shaft to position it at the lining start position.
At this time, a translation type actuator is connected to the suspension member 15 and then suspended by a crane truck.

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

The concrete sent by the screw blades 4a naturally falls from the lower end of the screw blades 4a sequentially in the falling cylinder 3 having a relatively large diameter without being filled. At this time, after an appropriate amount of quick-setting agent is continuously jetted from the nozzle 5, the mixture is sheared and mixed by the stirring rod 6 rotating at high speed while falling down the dropping cylinder 3, and then the rotating impeller 7 is rotated. It is thrown into the center.

Then, the concrete is supplied to the impeller 7
After the direction is changed in the direction perpendicular to the axis by the dispersing body 22 at the center portion of the blade and dispersed in all directions, the dispersing member 22 moves toward the outer periphery along the blade portion 35 by centrifugal force and is discharged in a substantially tangential direction.
The concrete thus centrifugally projected is scattered as a small mass over a wide area, collides with the inner wall surface of the shaft, and spreads in a thin film form, which is successively deposited and has a strong and uniform thickness on the entire peripheral surface of the inner wall of the shaft. A concrete lining layer having a thickness is formed.

At the same time as the concrete is centrifugally projected as described above, the above-mentioned translation type actuator is extended and contracted. Then, the vertical shaft inner wall lining device 1 moves up and down along the center line of the vertical shaft, and the projection position of the concrete on the inner wall surface of the vertical shaft by the impeller 7 can be smoothly displaced. Therefore, a concrete lining layer having a uniform thickness even in the depth direction can be formed smoothly and efficiently. At this time, a lining layer having a desired thickness is constructed by appropriately controlling the number of repetitions of the expansion / contraction operation of the translation actuator, the number and direction of rotation of the impeller driving motor 24, and the number of rotations of the feeder driving motor 12. be able to.

The screw rotor 4 and the stirring rod 6
Are driven independently of each other, so that the rotation of the stirring rod 6 and the impeller 7 can be continued even if the screw rotor 4 is stopped and the supply of concrete to the drop cylinder 3 is stopped. . On the other hand, when the screw rotor 4 is stopped because the concrete is not filled in the dropping cylinder 3, a little concrete falling in the falling cylinder 3 is sufficiently mixed with the quick-setting agent by the stirring rod 6. The centrifugal projection is quickly performed from the impeller 7. For this reason,
In conjunction with the wiping action of the large number of stirring rods 6 rotating at a high speed in the dropping cylinder 3, almost no concrete remains in the dropping cylinder 3 and the impeller 7.

In the present embodiment, the round stirring rod 6 is employed as the stirring member of the rotary mixing means. However, the stirring member in the present invention is not limited to such a shape. It may be.

[0033]

As described above, according to the present invention, the earth retaining material is shear-mixed by a plurality of agitating members radially protruding from the rotation shaft arranged at the center line position of the vertically disposed cylindrical dropping cylinder. At the same time, the fall cylinder is formed to have a relatively large diameter so that the earth retaining material falls naturally without being filled in the fall cylinder. Then, in the process of falling in the falling cylinder, the earth retaining material moves radially outward by centrifugal force and is evenly dispersed in the circumferential direction to be introduced into the center of the impeller. Therefore, since the earth retaining material is uniformly projected from the impeller toward the circumferential direction of the inner wall of the excavation, a lining layer having a uniform thickness over the entire circumference can be efficiently obtained.

In addition, when the lower end of the rotation shaft of the stirring member is connected to the center of the impeller so that the stirring member rotates at a high speed in conjunction with the impeller, the earth retaining material and the quick-setting agent can be rapidly formed. Since they can be mixed, they have a very large effect in obtaining a strong lining layer.

Further, since the earth retaining material which naturally falls without being filled in the falling cylinder 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 the earth retaining material from the material supply means is stopped, the earth retaining material in the dropping cylinder is promptly projected and discharged from the impeller, so that the earth retaining material containing the quick-setting agent remains in the falling cylinder and solidifies. This has the advantage that the formation of stiffness can be suppressed.

In particular, when a number of agitating members protruding to a position close to the inner surface of the drop cylinder are arranged from the quick-setting agent injection position to the lower impeller inlet, soil retaining material adhering to the inner surface of the drop cylinder can be removed. Due to the wiping action of peeling off, it is possible to significantly suppress the solidification 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 earth retaining material, so that the residence time in the drop cylinder is prolonged and the stirring effect can be enhanced.

When a vibrator is provided in the material tank, the earth retaining material in the material tank is sequentially and smoothly transferred toward the material supply means by the vibration of the vibrator. For this reason, the earth retaining material can be constantly introduced into the material supply unit, and the supply amount from the material supply unit to the drop 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 even more uniform.

In particular, when the vibrator is arranged on a rubber plate stretched so as to close a hole formed in the material tank, the amplitude is increased as compared with the case where the vibrator is directly arranged on a highly rigid steel material tank. However, the feed performance can be greatly improved, and stable supply can be achieved without being affected by differences in properties of the earth retaining material such as slump value, viscosity, and composition. In addition, there is an advantage that noise can be significantly reduced.

[Brief description of the drawings]

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

FIG. 2 is a side view of the shaft inner wall lining device shown in FIG. 1;

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 Drop cylinder 4 Screw rotor 4a Screw blade 4b Shaft 5 Nozzle 6 Stirring rod 7 Impeller 8 Body 8a Cylindrical part 8b Funnel-shaped part 9 Top plate 10 Input port 11 Cover plate 12 Feeder drive Motor 13 hood 14 connecting tool 15 hanging member 15a arm 15b head 16 guard 17 hole 18 rubber plate 19 vibrator 20 conduit 21 shaft 22 dispersing body 23 gantry 24 impeller driving motor 25 drive pulley 26 V belt 27 cylinder shaft 28 Cover 29 Leg member 30 Protective plate 31 Guard 32 Upper plate 33 Lower plate 34 Connecting member 35 Blade 36 Cable 37 Power supply connection box 38 Coupling

Continued on the front page (72) Inventor Yasuo Ugata 4-1 Egasaki-cho, Tsurumi-ku, Yokohama-shi, Kanagawa Prefecture Inside the Electric Power Research Laboratory, Tokyo Electric Power Company (72) Inventor Sakae Nakai 518-1, Komagaki, Nagareyama-shi, Chiba Mitsui (72) Inventor Masataka Uozumi 518-1, Komagaki, Nagareyama-shi, Chiba Mitsui Construction (72) Inventor Tatsuo Ito 518-1, Komagaki, Nagareyama-shi, Chiba Mitsui Ken (56) References JP-A-7-158380 (JP, A) JP-A-8-246475 (JP, A) JP-A 5-7796 (JP, U) JP-A 5-70676 ( JP, U) J. 7-8635 (JP, Y2) (58) Fields investigated (Int. Cl. ⁶ , DB name) E21D 5/00 E21D 5/12

Claims (4)

(57) [Claims] 1. A vertical shaft inner wall lining apparatus for lining an excavation inner wall of a shaft having a substantially circular cross section with a cement-based soil retaining material, wherein the vertical shaft is slidably lifted and lowered in the shaft to remove the fluid retaining material. A material tank to be housed, a drop cylinder provided at a lower portion of the material tank, material supply means for continuously introducing a retaining material in the material tank into the fall cylinder, and the dropping by the material supply means. A nozzle for continuously injecting the quick setting agent into the earth retaining material introduced into the cylinder, a rotary mixing means for mixing the earth retaining material falling in the falling cylinder with the quick accelerating agent, and Provided at the lower end, and an impeller for centrifugally projecting the earth retaining material lowered from the dropping cylinder and introduced into the center toward the excavation wall surface of the shaft, wherein 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. Shaft lining equipment to be used. 2. A plurality of agitating members protruding to a position close to an inner surface of the drop cylinder are provided over a region from a quick-setting agent injection position to a lower part of the impeller inlet. The vertical shaft inner wall lining device according to claim 1. 3. The lining apparatus according to claim 1, wherein a vibrator is provided in the material tank. 4. The lining apparatus according to claim 3, wherein the vibrator is disposed on a rubber plate stretched so as to close a hole formed in a side wall of the material tank. .