JPH0654076B2 - How to excavate a vertical shaft - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a shaft excavation method, and more particularly to a shaft excavation method capable of excavating vertically upward to the ground surface without causing a landslide even if the soil quality changes from a new or existing shield shaft.

[Prior art]

Generally, when a transmission line or a power transmission line such as a telephone line or a power line is laid with an underground cable, a horizontal shaft having a diameter of 3 to 5 m is dug and laid so that the repair can be easily performed later. To dig this side shaft (shield pit), first build a turret on the ground, install a device for discharging earth and sand, dig the vertical shaft to a predetermined depth, then bring the shield machine into the mine, Dig in the direction. In order to dig a shield pit (horizontal pit) in this way, a method using a shield machine in which the force of a jack is used as a propulsive force is adopted because it is more efficient than manual work. This method is also used for subway construction and sewer construction. That is, the pit shield machine is used to automatically dig. Then, when the shield pit (horizontal pit) is advanced for a predetermined distance, the vertical shaft is excavated at a predetermined position. In order to excavate the vertical shaft, a subordinate chamber was conventionally formed on the surface of the ground at a position corresponding to a predetermined position of the shield shaft, and the tunnel was excavated from the surface toward the shield shaft. However, in recent years, with the development of economic society,
Houses are densely built around the road, and cars and people are flooded on the road. When excavating a shaft on a densely packed road of such a house, a large work area is required to secure a material storage area by building a turret on the surface of the ground, and a large work area is required. ,
There are many cases where it is necessary to use the land of another person.
Due to noise generated during work on the ground, work on the ground is extremely limited, and it has become extremely difficult to work efficiently. In addition, even if the road width is wide, it may be necessary to completely block the road in order to raise a turret, etc., and it is extremely difficult to perform the work by completely blocking the road on conventional heavy roads. When the houses are crowded,
Due to noise generated during work on the ground, work on the ground is extremely limited, and it has become extremely difficult to work efficiently. Therefore, in recent years, when excavating a vertical shaft in a new or existing shield shaft, a method of excavating the vertical shaft from the shield shaft toward the surface of the ground is desired.

[Problems to be Solved by the Invention]

The stratum for excavating the vertical shaft is, for example,
m), clay layer (about 9 m), aquifer gravel layer (about 20 m), and Dotan layer (about 5 m). In this stratum, the shield pit (horizontal pit) is formed in the Dotan formation. Conventionally, a shield machine has been used to laterally excavate the Dotan formation. However, if you try to excavate the shield machine for excavating this shield pit vertically from the inside of the shield pit, the earth and sand excavated by the excavator will be excavated from the excavator and will immediately fall down. , The conventional shield machine does not have a structure to discharge quantitatively the earth and sand falling from above, so that the conventional shield machine is erected vertically in the shield pit to dig upward. There is a problem that the shaft excavation work cannot be performed by itself. In addition, when a conventional seed machine is set upright to excavate in the Dotan formation, the excavated earth and sand will drop directly downward. There is a problem that it is not possible to perform the work of discharging the earth and sand outside the mine using the shield mine. Moreover, in the stratum, as described above, there is a water-bearing gravel layer containing a large amount of water on the Dotan formation, and there is a particular problem when the shield machine advances to this water-bearing gravel layer.
That is, this water retention gravel layer has the property of collapsing into a brittle layer and is also an overflow layer. Therefore, if the shield machine is a fragile layer that collapses simply by excavating from below from below, if the shield machine enters the aerated gravel layer, support the shield machine on the excavated surface of the aerated gravel layer. Not possible, the excavation direction of the shield machine fluctuates, and the segments that make up the wall of the shaft cannot be assembled, and the collapse of the soil layer around the upper part cannot be prevented, causing the collapse of the ground surface. There is a problem that there is a property. In addition, the conventional shield machine cannot process the water discharged from the stagnant gravel layer, and there is a problem that a person cannot work under the shield machine as well as inside the shield machine. As described above, conventionally, there is a problem that the shaft cannot be excavated upward from the shield shaft to the surface of the earth. It is an object of the present invention to provide a method for excavating a vertical shaft that can excavate upward from a shield shaft vertically to the ground surface without causing landslides even if the soil quality changes.

[Means for Solving the Problems]

In order to achieve the above object, in the shaft excavation method of the present invention, in the vertical direction from the new or existing shield pit toward the surface of the ground, the length of the excavation blade is adjusted in accordance with the change in soil quality, and the cutting is performed. , Regardless of the amount of earth and sand generated according to the change in soil quality such as the earth and sand excavated, the amount of earth and sand that is excavated and dropped is controlled to excavate and the overflow and excavated earth and sand are concentrated in the central axis direction. It discharges quantitatively and makes the discharged earth and sand etc. spirally drop into the shield mine, and the earth pressure applied to the vertical shaft is supported by the pit wall to prevent the earth and sand from collapsing while excavating. .

[Action]

According to the method of excavating the vertical shaft configured as described above, even if the soil quality changes from the Dotan formation where the shield pit is formed to the aquifer gravel layer, the viscous layer, and the topsoil, it adapts to changes in the soil quality. It is possible to excavate, discharge the excavated earth and sand in a concentrated manner in the central axis direction, and drop the discharged earth and sand and the like spirally into the shield pit, so that the pressure applied to the excavated pit wall is supported. It is possible to efficiently excavate vertically upward from the shield pit to the ground surface while preventing the collapse.

【Example】

Examples of the present invention will be described below. FIG. 1 shows a schematic configuration diagram of the present invention. That is, the shaft 250 is excavated from the ground surface 200 to the ground surface 210, the clay layer 230, the water retention gravel layer 230, the Dotan layer 240,
A horizontal shaft (shield shaft) 260 is excavated laterally from the lowest point of the vertical shaft 250 by a shield machine 270.
In this way, the excavator 280 is dug to the predetermined point, and the vertical shaft 290 is excavated toward the subway chamber 300 provided on the surface of the earth.
Will be drilled in. In order to vertically excavate upward from the shield pit 260, the amount of soil and the like generated during excavation changes according to the change in soil quality that changes sequentially from the Dotan formation. Therefore, the length of the excavating blade is adjusted to adapt to changes in soil quality, and the amount of earth and sand produced by excavation is adjusted to a specified amount regardless of the nature of the soil, which changes as the drilling progresses. Control to become. Further, even when the amount of earth and sand or the like generated by excavation changes due to the change of the soil quality even if the length of the digging blade is adjusted, the amount of earth and sand or the like falling into the shield machine 270 is controlled. In addition, flood water, earth and sand, etc. that have come out after the start of excavation are concentrated at one location in the center of the shield machine and discharged downward. At the time of this discharge, flood water, earth and sand, etc. are spirally dropped into the shield pit. When excavating, the earth pressure applied from above is supported by the wall of the shaft to prevent the debris from collapsing. By excavating in this way, it is possible to excavate a vertical shaft from the shield pit to the surface of the ground while preventing the debris from collapsing. FIG. 2 shows the whole of the upward shield machine 1 showing the specific configuration of the excavator 280 as the specific method. In the figure, an upward shield machine 1 has a body 2 formed in a tubular shape. This body 2 is the upper body 3
And a middle body 4 and a lower body 5, and the upper body 3, the middle body 4 and the lower body 5 are separable. An excavator 6 is rotatably provided at the tip of the upper body 3.
Is installed. The excavator 6 is rotated by a hydraulic motor 10 that rotationally drives a pinion 9 that meshes with an internal gear 8 of a turntable 7. A shaft 11 is provided at the tip of the excavator 6, and cylinders 12 and 13 are rotatably fitted to the shaft 11. The cylinders 12 and 13 have a third
As shown in the drawing, the cutter bits 14 and 15 are provided in two rows facing each other. The cylinders 12 and 13 are shown in FIG.
As shown in FIG. 5, it is configured to rotate by a predetermined angle by link mechanisms 18 and 19 (not shown) which are operated by driving the jacks 16 and 17. As shown in FIG. 5, when the piston rod of the jack 16 is projected as shown by the arrow A, the cylinder 12 is rotated in the direction shown by the arrow B, and the cutter bit 14A is retracted,
The cutter bit 14B projects. The cutter bits 14A and 14B are selectively used, for example, when the cutter bit 14A is used for right rotation and the cutter bit 14B is used for left rotation. As shown in FIG. 3, face plates 20 and 21 are provided at the tip of the excavator 6 with the cutter bits 14 and 15 interposed therebetween. A slit 22 for discharging (falling) earth and sand excavated by the cutter bits 14 and 15 is provided between the face plate 20 and the cutter bits 14 and 15, and also between the face plate 21 and the cutter bits 14 and 15. In between
A slit 23 is provided. These slits 22, 2
3 is a jack 80, 81, 82, 8 as shown in FIG.
Sliding plates 84, 85, 8 shown in FIG.
The opening area can be changed by 6, 87. Further, between the cylinder 12 and the cylinder 13, a conical body 24 is provided in the approximate center, and the conical body 24 is divided into two at the center, and a groove 25 is formed. This groove 25
A center bit 26 is fitted in the. As shown in FIG. 2, the center bit 26 has a plurality of digging blades arranged at a predetermined interval in a line and in a mountain shape.
The center bit 26 can adjust the degree of protrusion of the blade from the conical body 24 by a hydraulic jack 27. As shown in FIG. 4, concave excavation plates 70 and 75 facing each other are provided at the bottom of the excavator 6. The earth discharging plates 70 and 75 are adapted to rotate according to the number of times of the excavating device 6. The excavation device 6 is in contact with the chamber 28 on the lower surface. Inside the chamber 28, skappers 29 are provided at appropriate locations (three locations at equal intervals (not shown in the present embodiment)). This scraper 29
Has a function of forcibly sending out the earth and sand and the like that have fallen from the slits 22 and 23 and accumulated in the chamber 28 to the lower side of the chamber 28. That is, the scraper 29 is provided with the rotary blades 31 on the plurality of arms 30.
The arm 1 is rotated by the arm 30 through the rotary joint 32 by using the rotation of the excavation device 6, and the earth and sand are sent out. The rotation speed of the scraper 29 is set by the gear ratio in the rotary joint 32, and the gear ratio is 1: 2 (twice as fast as the excavator 6) or 1: 3 (also 3). It is appropriate to set the speed twice as fast. A rotary feeder 34 is connected to the lower end of the chamber 28 via a gate valve 33. The gate valve 33 has a function of controlling the discharge amount of the earth and sand accumulated in the chamber 28.
Is configured to be opened and closed by the gate jack 33B. The casing 35 of the rotary feeder 34 is connected to the gate valve 33. Inside the casing 35, blades 37A, 37B, 37C, and 37D are attached in a radial manner around a rotary shaft 36, and are configured to rotate by closely sliding on the inner wall of the casing 35. A discharge port 38 is formed in the lower portion of the casing 35, and a cylindrical tube body 39 is connected below the discharge port 38. This cylinder 39 is
It has an upper cylinder 40 and a lower cylinder 41. Upper cylinder 4
On the outer peripheral surface of 0, the arm 42 is movable along the outer peripheral surface.
Is installed. A hoisting tool 43 is attached to the tip of the arm 42. This lifting tool 43
Winding up the wire rope 44, wire rope 4
4 has a function of lifting the scratched segment 500 on the hook 45 fixed to the tip of the wire 4. A cylinder 46 is rotatably fitted on the outer peripheral surface of the lower cylinder 41. The body of the jack 47 is fixed to the outer peripheral surface of the cylinder 46, and a tag 48 for mounting the segment 100 is fixed to the tip of the piston rod of the jack 47. The jack 47 is configured to be vertically slidable by a jack 49 fixed to the cylinder 46. Further, the cylinder 46 can be rotated by a hydraulic motor 50. Further, as shown in FIG. 6, jacks 51, 52, 53, 54, 55 for propelling the upward shield machine 1 are provided on the upper end portion of the middle trunk 4 of the upward shield machine 1.
The tip of the piston rod 56 is fixed. The body of this jack 51, 52, 53, 54, 55, 56 is
It is placed on the uppermost end of the assembled segment 600 and has the function of propelling the body 2 with the segment 101 as a scaffold. The body 2 is configured so that the claw 57 provided on the outer periphery of the middle body 4 prevents the excavation portion 6 from rotating and does not rotate when excavating by the cutter bits 14 and 15. Further, the inside of the cylindrical body 39 is configured as a spiral chute. A cylinder 58 for discharging earth and sand is connected to the lowermost end of the cylindrical body 39. This cylinder 58 is connected. A segment assembly deck 59 is attached to the top of the cylinder 58. Note that reference numerals 60 and 61 in FIG. 2 denote ladders hung on the segment 101. This ladder 60 and ladder 61
It is hung at a position slightly different from. This is a design for safety so that even if the user steps off the ladder 60, he / she will not fall to the bottom. Next, the operation of this embodiment will be described. First, in the shield pit (not shown), the upward shield machine 1 is set at a location where a vertical shaft is to be excavated. Next, the center bit 26 at the tip of the excavation device 6
Adjust the blade extension according to the soil type to be excavated. The cutter bits 14 and 15 are also adjusted according to the rotation direction of the excavation device 6. After that, jacks 51, 52, 53, 54, on top of the segment on the wall of the shaft,
55, 56 are placed, and the jacks 51, 52, 53,
The excavator 6 is rotated by driving the hydraulic motor 10 while driving 54, 55 and 56. By the rotation of the excavator 6, the center bit 26 and the cutter bit 14, 1
The earth and sand excavated by 5 are dropped into the chamber 25 through the slits 22 and 23. The earth and sand and the like are scraped to the center by the earth discharging plates 70 and 75, and sent to the rotary feeder 34 by the scraper 29 through the gate valve 33. This gate valve 33 changes the passage area of the earth and sand by the gate plate 33A when the soil is a soil that is likely to collapse like an aquifer gravel layer. Also,
If the soil is extremely soft and a large amount of earth and sand is falling without excavating at the excavation site, etc., stop the temporary discharge of earth and sand etc. when the discharge work can not catch up with the discharge speed of earth and sand etc. Therefore, work efficiency and safety such as closing the gate plate 33A are also taken into consideration. The earth and sand or the like sent to the rotary feeder 34 in this way is sent to the tubular body 39 by the blades 37 of the rotary feeder 34. In this tubular body 39, due to the action of the spiral chute, the earth and sand do not drop directly to the lowest point, but drop while moving in a spiral shape. In this way, the excavation device 6 is attached to the tip of the arm 42 while excavating the jacks 51, 52, 53, 54, 55, 56 for machine propulsion up to the full propulsion distance (distance where the piston rod extends). The segment 100 is lifted by the lifting tool 43, and the jacks 51, 52, 5
Segment 10 with scaffolding of 3, 54, 55, 56
Lift to a position above 1. For pouring, this jack 5
Any one of 1, 52, 53, 5, 55, 56,
For example, the jack 51 is reduced. Then, jack 5
In No. 1, the top of the segment 101, which was attracted to the tip side of the middle trunk and used as a scaffold, opens. The segment 100 previously hung up at the open position is pressed to the outer peripheral side by the jack 47 fixed to the duck 48, and the height is adjusted by the jack 49. Next pressed and set segment 10
Fix 0 with bolts. Next, the jack 52 is similarly reduced to the segment 101 on which the jack 52 has been scaffolded.
And the suspended segment 100 are fixed. Do the same for the jacks 53, 54, 55, and 56,
Assemble the segments over the entire circumference. Next, the segment 100 just assembled is used as a scaffold to excavate while rotating the excavation device 6 as described above. The cylinder 58 is added to the lower end of the tubular body 39 when several segments are assembled. In this manner, the segments are sequentially assembled, and the cylinders 58 are replenished to dig up the vertical shaft. In this embodiment, the segments are assembled in the body 2,
That is, it is characterized in that it is performed inside the middle body 4 and the lower body 5. That is, in FIG.
The lower body 5 is fitted on the outer side of 1B, and the next segment is assembled in this state. Therefore, segment 10
1A and 101B, the body 2 acts as a wall surface of the vertical shaft like the segment 101, and in this state, the body 2 is advanced and the segments 101A and 101B come into contact with the external soil, and the wall surface of the actual vertical shaft is first contacted. Will be configured. For this reason, even in the case of an aquifer gravel layer where the soil is brittle, the soil layer around the upper part is prevented from collapsing and the ground surface is prevented from sinking. That is, the pressure applied laterally to the upward shield machine 1 is applied to the lower body 5 of the body 2 and the segment 101.
It will be supported by the fitting part with A and 101B.

【The invention's effect】

According to the present invention, it is possible to efficiently excavate vertically upward from the shield pit toward the ground surface while supporting the pressure applied to the excavated pit wall to prevent the debris from collapsing. Further, according to the present invention, a change in soil quality of the soil layer, or
Even the same layer can fully respond to changes in contents,
Drilling of any layer can be possible. Further, according to the present invention, the discharged earth and sand or the like can be collected without spreading to the surroundings, and can be gradually dropped instead of being dropped at the lowest end at once. Furthermore, when excavating in the aquifer gravel layer, if the amount of earth and sand falling into the chamber due to the excavation is higher than the discharge work speed of the earth and sand, etc., the earth and sand from the excavation falls into the chamber. The amount can be suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram for explaining a shaft excavating method according to the present invention, and FIG. 2 is an upward shield machine showing a concrete embodiment of the shaft excavating method according to the present invention. Overall configuration diagram of
3 is a plan view of the upward shield machine shown in FIG. 2, FIG. 4 is a plan view with the face plate of FIG. 2 removed, and FIG. 5 is a sectional view taken along line AA of FIG. The drawing is a sectional view taken along the line AA in FIG. 1 ... Upward shield machine 6 ... Drilling equipment 14,15 ... Cutter bit 26 ... Center bit 28 ... Chamber 33 ... Gate valve 34 ... Rotary feeder 39 ... Cylinder

Claims (1)

[Claims] 1. A new or existing shield pit is vertically cut toward the surface of the earth in order to adjust the length of a digging blade in response to changes in soil quality, and to carry out cutting, according to changes in soil properties such as earth and sand excavated. Regardless of the amount of earth and sand generated, the amount of earth and sand excavated and dropped is controlled to excavate, and overflow and earth and sand that have been excavated are concentrated in the central axis direction and discharged quantitatively. A method for excavating a vertical shaft, characterized in that it is spirally dropped into the shield mine, and earth pressure applied to the vertical shaft is supported by a mine wall to prevent the collapse of earth and sand and the like for excavation.