JP4693586B2 - Circular shaft excavation method - Google Patents

Description

The present invention relates to a circular shaft excavation method for constructing a circular shaft using a circular casing in civil engineering construction work.

  As a construction method for constructing a deep shaft, for example, there is one disclosed in Patent Document 1. This method is a circular shaft excavation method in which a vertical shaft excavator is excavated by swinging or swiveling press-fitting of a circular casing. Next, insert a small-diameter circular casing into the large-diameter circular casing, insert a spacer in the tightening band, tighten the top of the small-diameter circular casing, and press-extrude and excavate. This is a circular shaft excavation method in which when a depth of the power shaft is reached, underwater concrete is cast on the bottom of a small-diameter circular casing to form a shaft bottom plate.

  FIG. 8 is a process diagram showing the excavation procedure by the excavation method of the circular shaft. First, as shown to Fig.8 (a), it excavates by the large diameter casing 31 which provided the excavation blade 30 in the lower end to the middle of the excavation depth of a shaft. However, in this figure, the shaft excavator part other than the grab bucket D and the large-diameter fastening band 41 is omitted. A large-diameter casing 31 is connected to a large-diameter casing 31 by a bolt (not shown) as a margin for gripping the tightening band 41, and is tightened by the large-diameter tightening band 41. The large-diameter fastening band 41 is press-fitted while being swung or swiveled by a circular shaft excavator, and excavated by the large-diameter casing 31. The large-diameter casing 31 is excavated and discharged with a grab bucket D.

  Next, as shown in FIG. 8B, the inner diameter of the large-diameter fastening band 41 is reduced by the spacer 42, the small-diameter casings 35 and 32 are gripped by the spacer 42, and the small-diameter casings 35 and 32 are placed in the large-diameter casing 31. Is pressed and excavated by the excavating blade 34, and the inside is replaced with a small diameter grab bucket E and excavated and discharged. In the figure, first, the second-stage small-diameter casing 32 is connected to the first-stage small-diameter casing 35 by welding or bolting. A state where the excavation blade 34 at the tip of the first-stage small-diameter casing 35 is excavated by press-fitting while turning is shown.

  Next, as shown in FIG. 8C, after completion of excavation by the small-diameter idle casing 33 attached as a grip for the small-diameter casings 35 and 32 and the spacer 42, the bottom slab concrete 36 and the connecting concrete 37 are placed.

  FIG. 8D shows a state where the shaft is completed. After the concrete has solidified, the water in the shaft will be changed. Unnecessary small-diameter casing 32 and small-diameter idle casing 33 are removed.

  In the case of this conventional circular shaft excavation method, the length of the small-diameter casing is usually 3 m or less. Therefore, in the case of a deeper shaft, a plurality of small-diameter circular casings are connected by welding or bolting, and the large-diameter casing 31 is connected. It is necessary to lower to the bottom.

  In this connection work, the first-stage circular small-diameter casing 35 is put into the large-diameter casing 31 by a crane (not shown), and is fastened and fixed by the fastening band 41 of the circular shaft excavator, and then the second-stage The small-diameter circular casing 32 is hung from the first-stage small-diameter circular casing 35 with a crane, and the first-stage and second-stage connections are performed.

After the connection work is completed, the connected first and second stage small-diameter circular casings 35 and 32 are suspended by a crane, the fastening band 41 is opened, the small-diameter circular casings 35 and 32 are lowered, and then the second stage. A circular casing 32 having a small diameter is fixed with a fastening band 41.
This operation is repeated until the tip of the small-diameter circular casing reaches the bottom of the large-diameter casing 31.

  Even if it is not a deep shaft, when recovering a small-diameter circular casing, the small-diameter circular casing is pulled out by one stroke with a circular shaft excavator, and then a small-diameter circular casing is extracted with a crane or the like. In a state where the circular casing is suspended, the fastening band 41 is grasped and the small-diameter circular casing is recovered.

  Also, in the case of a heavy casing such as a concrete circular casing, the casing may sink due to its own weight, so a method of holding the casing with a crane when swinging or changing the swivel band is taken. Yes.

  Even if it is not a deep shaft, if the frictional resistance of the natural ground increases, the swinging / turning torque becomes larger than that during the swinging / turning operation due to the first static friction after stopping.

Japanese Patent No. 3420926

  As described above, in a multi-stage shaft, as the number of small-diameter circular casings connected increases, the weight increases, so a large crane is required. Therefore, the construction cost will be high.

  Similarly, when a small-diameter circular casing is pulled out and collected, a crane corresponding to the weight of the entire casing is required.

  Even in the case of a circular casing made of concrete, the weight is so large that it may self-sink due to its own weight, and a crane corresponding to the weight of the casing is necessary when changing the swinging / swivel band.

  Furthermore, in order to cope with static friction of natural ground, it is necessary to increase the swing / swing torque of the swing / press-fit cylinder.

According to the present invention, it is necessary to further increase the torque of a swing cylinder or a hydraulic motor that moves a casing against a static friction between a natural ground and the casing without increasing the size of a crane for hanging a circular casing. The aim is to provide no circular shaft excavation method .

In order to solve the above problems, the circular shaft excavation method of the present invention is:
A major band that holds the outer periphery of the circular casings grayed,
A subband that is at a different height from the main band and holds the outer periphery of the circular casing;
Main band fastening means for fastening the main band to the outer periphery of the circular casing;
Elevating means for elevating the main band;
Main band driving means for swinging or turning the main band;
It is a circular shaft excavation method having the following steps using a circular shaft excavator provided with an auxiliary band fastening means for fastening the secondary band to the outer periphery of the circular casing .
(1) A step of tightening an upper portion of a large-diameter circular casing with the main band and performing press-fitting excavation to the middle of the shaft to be excavated by using the main band driving means and the elevating means.
(2) A step of placing a first-stage small-diameter circular casing provided with an excavating blade at the tip into the large-diameter circular casing with a crane and fixing with the main band.
(3) A second-stage small-diameter circular casing having no excavating blade is suspended by a crane on the first-stage small-diameter circular casing so as to be centered, and the first-stage small-diameter circular casing and the above-mentioned 2 A step of connecting the small-diameter circular casing at the stage.
(4) The first-stage small-diameter circular casing is fastened and fixed with the auxiliary band, the main band is opened, the main band is pulled out using the lifting means, and the main band A step of fixing the small-diameter circular casing at the stage.
(5) Next, a step of lowering the first-stage small-diameter circular casing by opening the subband and lowering the main band to the maximum press-fitted state using the elevating means.
(6) Next, tightening the subband, opening the main band, and using the elevating means to bring the main band into a maximum drawn state.
(7) When the steps (4) to (6) are repeated until the upper surface of the uppermost small-diameter circular casing is slightly above the main band, the third-stage small-diameter circular casing without the excavating blade Is suspended from the second-stage small-diameter circular casing with the center thereof, and the second-stage small-diameter circular casing is connected to the third-stage small-diameter circular casing.
(8) A step of repeating steps (4) to (7) while increasing the number of steps of the small-diameter circular casing until the tip of the first-stage small-diameter circular casing reaches the bottom of the large-diameter casing.
(9) The secondary band is tightened, the main band is opened, the main band is raised by the elevating means, the upper portion of the uppermost small-diameter circular casing is fastened with the main band, the secondary band is opened, and the main band driving means Then, while swinging or turning the uppermost small-diameter circular cylinder, the ground is excavated with the excavating blade at the tip of the first-stage small-diameter circular cylinder, and the shaft is circular up to a predetermined depth. Drilling process.

In the present invention, the circular shaft excavation work is performed according to the following procedure.
(1) Up to the middle of a shaft to be excavated by a circular shaft excavator by tightening the upper part of the large-diameter circular casing with a main band in the same manner as in the past (for example, a method for excavating a circular shaft described in Patent Document 1) Press-fitting excavation.
(2) The first stage of the small-diameter circular casing is put into the large-diameter casing with a crane and fixed with the main band.
(3) Next, the second stage of the small-diameter circular casing is suspended with the crane centered on the first-diameter small-diameter circular casing, and the first and second stages are connected.
(4) Next, the secondary band of the circular shaft excavator is fastened and fixed, the main band is opened, the main band is pulled out using the lifting means, and the small-diameter circular casing is fixed with the main band.
(5) Next, the secondary band is opened, the main band is lowered to the maximum press-fitted state using the lifting means, and the small-diameter circular casing is lowered.
(6) Next, the sub-band is tightened, the main band is opened, and the main band is pulled out to the maximum with the lifting means.
(7) When the operations of (4) to (6) are repeated until the upper surface of the uppermost small-diameter circular casing is slightly above the main band , the small-diameter circular casing is removed in the same manner as in the step (3). The third stage is suspended with the crane centered on the second-stage small-diameter circular casing, and the second-stage small-diameter circular casing and the third-stage small-diameter circular casing are connected .
(8) Repeat steps (4) to (7) until the tip of the first-stage small-diameter circular casing reaches the bottom of the large-diameter casing.
(9) Tighten the secondary band, open the main band, raise the main band with the lifting means, tighten the upper part of the uppermost small-diameter circular casing with the main band, open the secondary band, and open the upper band with the main band driving means The ground is excavated with the excavating blade at the tip of the first-stage small-diameter circular cylinder, and the circular shaft is excavated to a predetermined depth by press-fitting with the lifting means while swinging or turning the small-diameter circular cylinder.

  When a small-diameter circular casing is pulled out and collected, the small-diameter circular casing is pulled out by one elevating means, and then the small-diameter circular casing is fixed with a sub-band to change the main band. The small-diameter circular casing is fixed by the main band, the sub-band is opened, the small-diameter circular casing is pulled out by the lifting means, and this operation is repeated to collect the small-diameter circular casing.

  If ground friction increases and the main band cannot be swung or swiveled, a small-diameter circular casing is fixed between the main band and subband by providing a swinging means on the subband. The small-diameter circular casing can be moved against the static friction of natural ground by the moving / turning torque and the swinging torque of the auxiliary band. Once the small-diameter circular casing moves, the secondary band is opened, and the small-diameter circular casing can be swung and swiveled only by the main band.

According to the present invention, by using the main band and the sub band, it is sufficient to prepare a crane that can suspend one stage of a small-diameter circular casing, which reduces the construction cost.
Further, by providing the sub-band with the swinging means, the small-diameter circular casing can be moved against the static friction between the natural ground and the small-diameter circular casing by the swinging torque of the main band and the sub-band.

  1 is an overall configuration diagram showing a circular shaft excavating apparatus according to an embodiment of the present invention, FIG. 2 is a plan view in which a boom and a hydraulic bucket portion are omitted in FIG. 1, and FIG. 3 is a circular shaft excavating according to an embodiment of the present invention. The apparatus is shown, (a) is sectional drawing at the time of a fall, (b) is sectional drawing at the time of a raise. FIG. 4 is a plan view of the base frame of the circular shaft excavator according to the embodiment of the present invention.

  In these drawings, the shaft excavator 1 includes a base machine 2 that can travel, a boom 3 that can be turned and raised from the base machine 2, and a hydraulic bucket 4 that is attached to the tip of the boom 3. Yes. A circular shaft excavator 6 is fixed to the base machine 2 by a connecting device 5. The circular shaft excavation device 6 has a base frame 7 and an elevating frame 8, and the elevating frame 8 is driven up and down with respect to the base frame 7 by an elevating cylinder 9 that is an elevating means.

  As shown in FIG. 3, a main band 10 is pivotally attached to the elevating frame 8 by a pivot bearing 11, and a subband 12 is attached to the base frame 7.

  As shown in FIG. 2, the elevating frame 8 has a main band tightening cylinder (not shown) as a main band tightening means for tightening the main band 10 against the outer periphery of a circular casing (described later), and the main band 10 is shaken. A hydraulic motor 13 is provided as a main band driving means for moving or turning.

  As shown in FIG. 4, the base frame 7 has a secondary band fastening cylinder 14 as a secondary band fastening means for fastening the secondary band 12 to the outer periphery of a circular casing (described later), and a secondary band for swinging the secondary band 12. A sub-band rocking cylinder 15 is provided as rocking means.

  Next, the circular shaft excavation method by the circular shaft excavation apparatus of this Embodiment is demonstrated using FIGS.

(1) FIG. 5 (a) is a conventional method (for example, a method for excavating a circular shaft described in Patent Document 1) in which a drilling blade 21 is provided at the lower end until the middle of the shaft excavation depth. The state where it is excavated by the diameter casing 20 is shown. In this case, the upper portion of the large-diameter casing 20 is fastened with the main band 10 and the circular shaft excavator 6 performs press-fitting excavation halfway through the shaft to be excavated.
Next, the inner diameter of the main band 10 is reduced by the main band spacer 22, and the inner diameter of the sub band 12 is reduced by the sub band spacer 23. The first stage of the small-diameter circular casing 24 provided with the excavating blade 25 at the tip is put into the large-diameter casing 20 by a crane.

(2) Next, as shown in FIG. 5B, the small-diameter circular casing 24 is fixed by the main band 10 to which the main band spacer 22 is attached.

(3) Next, as shown in FIG. 5 (c), the second-stage small-diameter circular casing 26 is suspended from the first-stage small-diameter circular casing 24 by a crane (not shown). First stage and second stage connection work (welding) is performed.

(4) Next, as shown in FIG. 6 (a), the first-stage small-diameter circular casing 24 is fastened and fixed by the secondary band 12 of the circular shaft excavator 6, the main band 10 is opened, and the elevating cylinder 9 is The main band 10 is pulled out to the maximum, and the small-diameter circular casing 24 is fixed by the main band 10.

(5) Next, as shown in FIG. 6B, the sub-band 12 is opened, and the main band 10 is lowered to the maximum press-fitted state using the elevating cylinder 9. This state is shown in FIG.

(6) Next, as shown to Fig.7 (a), the subband 12 is tightened, the main band 10 is opened, and the main band 10 is made into the maximum extraction state using the raising / lowering cylinder 9. FIG.

(7) By repeating this operation, as shown in FIG. 7B, when the upper surface of the second-stage small-diameter circular casing 26 is slightly above the main band 10 , the next third-stage small-diameter circle The casing 27 is suspended from a second-stage small-diameter circular casing 26 with a crane, and the second-stage small-diameter circular casing 26 and the third-stage small-diameter circular casing 27 are connected .

(8) This operation is repeated until the tip of the small-diameter circular casing 24 reaches the bottom of the large-diameter casing 20. In the example shown in FIG. 7C, a third- stage small-diameter circular casing 27 is connected to the upper part of the second- stage small-diameter circular casing 26.
(9) In this state, the subband 12 is tightened, the main band 10 is opened and the elevating cylinder 9 is raised, the upper portion of the third- stage small-diameter circular casing 27 is tightened with the main band 10, and the subband 12 is opened. The ground is excavated by the excavating blade 25 at the tip of the first- stage small-diameter circular cylinder 24 by press-fitting with the elevating cylinder 9 while the small-diameter circular cylinder 27 is swung or swiveled by the hydraulic motor 13, and a predetermined depth is obtained. Drill a circular shaft. The earth and sand in the small-diameter circular casings 24, 26 and 27 are discharged by the hydraulic bucket 4.

  When the small-diameter circular casings 24, 26, and 27 are pulled out and collected, the small-diameter circular casings 24, 26, and 27 are pulled out by the lifting cylinder 9 for one stroke, and then the small-diameter circular casing 24 is pulled out by the auxiliary band 12. , 26 and 27 are fixed, and the main band 10 is changed. The small-diameter circular casings 24, 26, and 27 are fixed by the main band 10, the secondary band 12 is opened, the small-diameter circular casings 24, 26, and 27 are pulled out by the elevating cylinder 9, and this operation is repeated. , 26 and 27 are collected.

  When the natural friction of the natural ground becomes large and the main band 10 cannot swing or turn, the small casings 24, 26, and 27 are fixed by the main band 10 and the subband 12, and the main band 10 is fixed by the hydraulic motor 13. The subband 12 is simultaneously swung by a subband rocking cylinder 15. As a result, the small-diameter circular casings 24, 26, and 27 can be moved against the static friction of the natural ground by the swinging / turning torque of the main band 10 and the swinging torque of the subband 12. Once the small-diameter circular casings 24, 26, 27 move, the subband 12 is opened, and the small-diameter circular casings 24, 26, 27 can be swung and swiveled only by the main band 10.

According to the present invention, it is necessary to further increase the torque of a swing cylinder or a hydraulic motor that moves a casing against a static friction between a natural ground and the casing without increasing the size of a crane for hanging a circular casing. As a method for excavating circular shafts, it can be applied to civil construction work for excavating circular shafts.

It is a whole lineblock diagram showing the circular shaft excavation device concerning the embodiment of the present invention. It is the top view which abbreviate | omitted the boom and the hydraulic bucket part in FIG. BRIEF DESCRIPTION OF THE DRAWINGS The circular shaft excavation apparatus which concerns on embodiment of this invention is shown, (a) is sectional drawing at the time of a fall, (b) is sectional drawing at the time of a raise. It is a top view of the base frame of the circular shaft excavation apparatus which concerns on embodiment of this invention. It is explanatory drawing of the circular shaft excavation method by the circular shaft excavation apparatus of this Embodiment. It is explanatory drawing of the circular shaft excavation method by the circular shaft excavation apparatus of this Embodiment. It is explanatory drawing of the circular shaft excavation method by the circular shaft excavation apparatus of this Embodiment. It is process drawing which shows the excavation procedure by the excavation method of the conventional circular shaft.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vertical shaft excavator 2 Base machine 3 Boom 4 Hydraulic bucket 5 Coupling device 6 Circular shaft excavator 7 Base frame 8 Lifting frame 9 Lifting cylinder 10 Main band 11 Slewing bearing 12 Subband 13 Hydraulic motor 14 Subband tightening cylinder 15 Subband swing Moving cylinder 20 Large diameter casing 21 Excavation blade 22 Main band spacer 23 Sub band spacer 24, 26, 27 Small diameter circular casing 25 Excavation blade

Claims (2)

A major band that holds the outer periphery of the circular casings grayed,
A subband that is at a different height from the main band and holds the outer periphery of the circular casing;
Main band fastening means for fastening the main band to the outer periphery of the circular casing;
Elevating means for elevating the main band;
Main band driving means for swinging or turning the main band;
A circular shaft excavation method having the following steps using a circular shaft excavating device provided with an auxiliary band tightening means for tightening the sub band on the outer periphery of the circular casing .
(1) A step of tightening an upper portion of a large-diameter circular casing with the main band and performing press-fitting excavation to the middle of the shaft to be excavated by using the main band driving means and the elevating means.
(2) A step of placing a first-stage small-diameter circular casing provided with an excavating blade at the tip into the large-diameter circular casing with a crane and fixing with the main band.
(3) A second-stage small-diameter circular casing having no excavating blade is suspended by a crane on the first-stage small-diameter circular casing so as to be centered, and the first-stage small-diameter circular casing and the above-mentioned 2 A step of connecting the small-diameter circular casing at the stage.
(4) The first-stage small-diameter circular casing is fastened and fixed with the auxiliary band, the main band is opened, the main band is pulled out using the lifting means, and the main band A step of fixing the small-diameter circular casing at the stage.
(5) Next, a step of lowering the first-stage small-diameter circular casing by opening the subband and lowering the main band to the maximum press-fitted state using the elevating means.
(6) Next, tightening the subband, opening the main band, and using the elevating means to bring the main band into a maximum drawn state.
(7) When the steps (4) to (6) are repeated until the upper surface of the uppermost small-diameter circular casing is slightly above the main band, the third-stage small-diameter circular casing without the excavating blade Is suspended from the second-stage small-diameter circular casing with the center thereof, and the second-stage small-diameter circular casing is connected to the third-stage small-diameter circular casing.
(8) A step of repeating steps (4) to (7) while increasing the number of steps of the small-diameter circular casing until the tip of the first-stage small-diameter circular casing reaches the bottom of the large-diameter casing.
(9) The secondary band is tightened, the main band is opened, the main band is raised by the elevating means, the upper portion of the uppermost small-diameter circular casing is fastened with the main band, the secondary band is opened, and the main band driving means Then, while swinging or turning the uppermost small-diameter circular cylinder, the ground is excavated with the excavating blade at the tip of the first-stage small-diameter circular cylinder, and the shaft is circular up to a predetermined depth. Drilling process. Sub-band swinging means for swinging the sub-band is provided , and when the main band cannot be swung or swiveled in the step (9), a small-diameter circular casing is fixed between the main band and the sub-band. 2. The circular shaft excavation method according to claim 1, wherein the main band is simultaneously swung by the main band driving means, and the sub band is swung simultaneously by the sub band rocking means .

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