JP4039978B2 - Construction method of concrete lining of shaft wall - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for constructing a concrete lining to be constructed on a wall of a shaft excavated when a shaft is excavated from a ground surface side to an underground deep layer by a shaft excavator.
[Prior art]
In order to construct an underground structure such as an oil reservoir or a radioactive waste storage in the deep underground, for example, it is necessary to first excavate a shaft from the surface side to the construction position of the planned underground structure. Conventionally, as a means for excavating such a vertical shaft, it is generally carried out by digging down by blasting. However, it is difficult to efficiently excavate a vertical shaft having a predetermined diameter by this method.
[0003]
For this reason, a concrete lining that is provided with excavation means such as a hole hammer at the lower end of a scaffolding base suspended from a ground surface so as to be movable up and down by a rope, and that has been constructed on the excavation wall first above the scaffolding base. A shaft excavation device has been developed that has a movable form frame slidably supported along the excavation wall surface at the lower end of the excavator and further has a discharge pipe for discharging excavated earth and sand upward (see, for example, Patent Document 1).
[0004]
[Patent Document 1]
JP-A-62-276192 (pages 2 to 3, FIG. 1).
[0005]
[Problems to be solved by the invention]
According to this apparatus, a shaft having a predetermined diameter can be efficiently dug down vertically by the excavating means, and a movable frame is arranged along the excavation wall every time a shaft having a certain length is excavated. By placing concrete between the movable formwork and the excavation wall, it is possible to easily construct a concrete lining, but the lower end of the concrete lining is not supported on the ground, and Therefore, the concrete lining slides downward along the excavation wall surface due to its large weight, and there is a possibility that a large accident will occur. It was.
[0006]
In addition, a waterproof sheet is usually stretched on the wall excavated by the excavator to prevent intrusion of groundwater, and a concrete is placed between the waterproof sheet and the movable formwork to cover the concrete lining. Since it is constructed, there is a problem that the inner surface of the waterproof sheet becomes a sliding surface and the concrete lining becomes easier to slide downward.
[0007]
In addition, since the movable form is suspended from the lower end of the concrete lining that has been built in advance through a screw mechanism or the like, it can be slid up and down. In addition, the scaffold must be replaced with the concrete lining side below, and the scaffolding can not be lifted up and down in the shaft alone unless the rope is operated from the surface side. However, there is a problem in that it is difficult to perform the work efficiently because it takes time for the bar arrangement work and the tension sheet installation work.
[0008]
The present invention has been made in view of such problems, and the object of the present invention is to make it possible to reliably and firmly support the concrete lining against the vertical shaft wall of the vertical shaft, and to The object of the present invention is to provide a method for constructing a concrete lining of a shaft wall for excavation that can be efficiently constructed.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the concrete lining method for a shaft wall of the shaft according to the present invention, as described in claim 1, is applied to the surface of the drill wall every time the ground is excavated by the shaft excavator. Then, after excavating a part of the excavation wall surface in the direction of expanding the diameter, the excavation recess is formed, and then the mold frame is assembled along the excavation wall surface, and then concrete is placed between the mold frame and the excavation wall surface. Then, a concrete lining is constructed, and a convex portion fitted and locked to the excavation concave portion is formed by hardening of the concrete filled in the excavation concave portion.
[0010]
In the concrete lining construction method, the invention according to claim 2 excavates the shaft by rotating the cutter plate disposed at the lower end of the shaft excavator, and the outer periphery of the cutter plate is radially arranged. An excavation recess is formed by projecting an excavation blade such as a disk cutter provided so as to freely move in and out.
[0011]
Moreover, the invention which concerns on Claim 3 has installed the support | pillar of fixed height toward the upper direction center part of the upper end of the said shaft excavator, and several sheets which can be expanded / contracted radially to the outer periphery of the upper half part of this support | pillar On the other hand, a scaffolding base is movably arranged in the lower half, and the formwork piece is expanded to assemble the formwork along the vertical excavation wall and use the scaffolding base. This is characterized by performing bar arrangement work on the inside of the mold.
[0012]
[Action]
When a shaft is excavated in a direction directly below the ground by a shaft excavator , a recess is formed by excavating a part of the excavation wall in the direction of expanding the diameter, and a certain length of the excavation wall having the recess Each time a dig is excavated, a mold is assembled along the excavation wall, and concrete is placed between the mold and the excavation wall so that the outer surface has a convex portion that fits and locks into the concave portion. Concrete lining is built.
[0013]
Furthermore, the shaft having a constant diameter can be efficiently excavated by rotating the cutter plate disposed at the lower end of the shaft excavator while rotating, and the outer periphery of the cutter plate can be radially expanded. By projecting an excavating blade made of a gauge cutter or the like provided so as to be able to appear and retract, a concave portion having a desired length and a desired depth can be formed continuously or intermittently in a desired portion of the shaft being excavated. In addition, this recessed part can be formed not only by protrusion of excavation blades, such as the said disk cutter, but also by making an excavator main body swing freely with respect to a gripper by operation of a gripper jack.
[0014]
In addition, a column having a fixed height is erected upward at the center of the upper end of the shaft excavator, and a plurality of mold pieces that can be expanded and contracted in the radial direction are disposed on the outer periphery of the upper half of the column. As a result, the formwork piece automatically descends to the concrete lining position when the shaft excavator is excavated for a certain length to the depth where the next concrete lining is possible, and the formwork piece is expanded at this position. By assembling the formwork, the construction of the concrete lining can be performed accurately and efficiently. In addition, by placing the scaffolding platform on the above-mentioned column so as to be movable up and down, the scaffolding platform can be raised during concrete lining to check the excavation wall, stretch the waterproof sheet, and even into the formwork. It is possible to easily attach the wife formwork to the lower bar opening of the formwork or the formwork.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Next, a specific embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal front view of a part of a concrete lining 2 constructed on the excavation wall surface 1 of a vertical shaft A. In FIG. 1, a recess 3 made of a circumferential groove is formed by excavation in the length direction thereof, that is, in the depth direction of the shaft A, while the concrete lining 2 is formed in a cylindrical shape having a constant thickness. Further, a convex portion 4 having the same cross-sectional shape as that of the concave portion 3 is integrally projected on the portion facing the concave portion 3 in the concrete lining 2 so as to be continuous over the entire circumference. . And the lining structure which supported the concrete lining 2 on the shaft wall 1 by making this convex part 4 fit and latched to the said recessed part 3 is comprised.
[0016]
Further, in order to prevent the underground water from entering the shaft A, a waterproof sheet 5 is entirely stretched on the shaft excavation wall 1, and the concrete lining 2 is connected to the excavation wall 1 via the waterproof sheet 5. It is built in. Before the waterproof sheet 5 is stretched, a primary lining concrete layer 2A made of sprayed concrete is provided on the shaft wall 1 and the waterproof sheet 5 is stretched on the primary lining concrete layer 2A. ing. Therefore, although the secondary lining concrete layer is formed by the concrete lining 2 constructed on the waterproof sheet 5, when excavating the shaft A in the ground where there is no possibility of ingress of groundwater. The concrete lining 2 may be constructed directly on the excavation wall surface 1 without providing the waterproof sheet 5.
[0017]
The depth, vertical width, etc. of the concave portion 3 formed by excavation in the diameter expansion direction of the excavation wall surface 1 can support the weight of the concrete lining portion between the convex portions 4, 4 adjacent in the vertical direction in the concrete lining 2. The depth and vertical width that can be set. That is, the weight of the concrete lining 2 is supported on the lower surface of the concave portion 3 through the convex portion 4, but the support reaction force acts as a shearing force on the convex portion 4 and is formed in the same cross-sectional shape as the concave portion 3. If the protruding width and the vertical width of the protruding portion 4 are narrow, the protruding portion 4 is sheared by the shearing force, and the concrete lining 2 may slide down along the excavation wall surface 1.
[0018]
Therefore, the concave portion 3 and the convex portion 4 are supported so that the weight of the concrete lining portion between the convex portions 4 and 4 adjacent to each other can be supported by the locking force between the convex portion 4 and the concave portion 3. The size of the cross-sectional shape and the length in the circumferential direction with respect to the shaft A are set.
[0019]
Moreover, in the said embodiment, although the recessed part 3 excavated and formed in the diameter-expansion direction on the excavation wall surface 1 consists of a circumferential groove, it may consist of a spiral groove, or, It may be composed of discontinuous grooves formed by excavation at predetermined intervals in the length direction and the circumferential direction.
[0020]
FIG. 2 is a simplified longitudinal front view of a shaft excavator that digs down the shaft A while building the concrete lining 2, and the excavator body B is the lower end side of the small-diameter vertical tube portion 11 provided at the center thereof. A cutter plate 12 is rotatably arranged. The cutter plate 12 is provided with a drilling blade 12a such as a large number of disc cutters for excavating the ground on the plate surface, and provided with an excavating earth and sand intake opening 12b communicating with the upper and lower surfaces. In several places, excavation blades 12a ', which are also made of disk cutters, etc., are provided so as to be able to appear and disappear in the radial direction. As a mechanism for moving the excavating blade 12a ′, for example, a hydraulic jack 12c is attached to the back side (the upper surface side in the drawing) of the outer periphery of the cutter plate 12, and the excavating blade 12a ′ is attached to the rod end of the hydraulic jack 12c. A fixed structure is adopted.
[0021]
In addition, a central portion of the lower surface of the horizontal fixed support base 13 that also serves as a fixed scaffolding base is integrally fixed to an upper end of the small-diameter vertical cylindrical portion 11, and the upper surface central portion of the horizontal fixed support base 13 is fixed upward. A column 14 having a height is vertically erected and fixed, and a scaffold base 15 is arranged on the column 14 so as to be movable up and down.
[0022]
The support column 14 may be erected by directly fixing the lower end thereof to the upper surface of the horizontal fixed support base 13, but in the figure, the lower end of the support column 14 is fixed on a flat rectangular support frame 13a. The support frame 13a is connected and supported on the horizontal fixed support base 13 via four level adjusting devices 16. With this configuration, even when the excavator body B tilts during excavation, the column 14 can be kept vertical, and therefore the scaffold base 15 can be kept horizontal and the scaffold base 15 can be No contact with 1.
[0023]
The support column 14 includes four vertical column members 14a that are erected in parallel from each other at four corners of the support frame 13a and at equal intervals in the front, rear, left, and right, and these vertical column members are connected and fixed. It is composed of a large number of diagonal beams 14b and horizontal beams 14c combined in a truss shape, and is lifted up and down from the horizontal fixing base 13 to the upper end in a hollow surrounded by four vertical column members 14a. Stairs 17 are provided in a zigzag shape, and landings 17a are formed at regular intervals in the length direction during the ascent / descent of the elevating stairs 17.
[0024]
The above-mentioned scaffold base 15 disposed on the column 14 so as to be movable up and down is formed in a horizontal disk shape having a smaller diameter than the vertical shaft A excavated by the excavator body B, and at the center thereof, as shown in FIG. In addition, a rectangular hole 15a through which the support column 14 is inserted is provided, and a handrail 15b having a constant height is erected upward at the outer peripheral edge portion.
[0025]
As an elevating drive mechanism 18 for moving the scaffold base 15 up and down with the support column 14 as a guide, a fixed vertical rack 18a is integrally provided on the vertical column member 14a of the support column 14, while a corner of the rectangular hole 15a of the scaffold platform 15 is provided. A structure is employed in which a lifting drive motor 18b is mounted at the corner, and a pinion 18c fixed to the rotating shaft of the lifting drive motor 18b is engaged with the fixed vertical rack 18a.
[0026]
The vertical movement range of the scaffold base 15 with respect to the support column 14 is performed in the central portion in the length direction from the lower end of the support column 14, that is, the lower half of the support column 14. Therefore, the vertical rack 18a has a length from the lower end of the support column 14. It is provided in the part reaching the middle part of the direction. A movable mold 19 is disposed on the upper half side of the column 14.
[0027]
This movable mold 19 is formed by connecting a plurality of fixed-length mold pieces 19a curved in a convex arc shape along the excavation wall surface 1 of the shaft T so as to expand and contract in a radial direction. The upper end of the frame piece 19a is suspended by a plurality of chain blocks 21 suspended from the lower surface of the outer peripheral portion of the disk-shaped fixed base frame 20 fixed to the upper end of the support column 14. The fixed frame 20 is fixed to a portion having a predetermined distance downward from the upper end of the column 14 with the column 14 inserted through a rectangular hole 20a (shown in FIG. 4) provided in the center thereof. The outer peripheral end face is brought close to the excavation wall surface 1 of the shaft A, and the plurality of chain blocks 21 are supported on the lower surface of the outer peripheral portion so as to be movable in the radial direction of the fixed frame 20. A scaffold frame 22 with a scaffold plate stretched is attached to the inner peripheral surface of the mold piece 19a.
[0028]
Further, a top plate 23 having the same shape and the same shape as the fixed base frame 20 is fixed to the upper end of the column 14, and a concrete hopper 24 is installed on the top plate 23, and is connected to the concrete hopper 24. The lower end of the communicating concrete supply pipe 25 is formed so as to face downward from the lower end of the lining concrete 2 previously constructed on the excavation wall surface 1 of the shaft A.
[0029]
On the other hand, the cutter plate 12 has an arm member 12d projecting from the outer peripheral end thereof in the inner diameter direction, and the inner ends of these arm members 12d are integrally fixed to the ring member 12e, and the ring member 12e is fixed to the excavator body. B is rotatably supported on the outer periphery of the lower end of a circular fixed frame 26 integrally fixed to the outer peripheral surface of the lower end of the small-diameter vertical cylinder 11 forming the central body of B, and the inner periphery of the ring member 12e The small rack 28 fixed on the rotary shaft of the cutter plate driving motor 27 installed on the circular fixed frame 26 is engaged with the circular rack 12f provided on the surface, and the cutter plate 12 is rotated by driving the motor 27. It is configured as follows.
[0030]
Further, on the outer peripheral surface of the circular fixed frame 26, the inner end portions of the inclined jack 30 inclined downward and the inclined jack 31 inclined upward at predetermined intervals in the circumferential direction are connected and supported so as to be rotatable in the vertical direction. The outer ends of the inclined jacks 30 and 31 are connected to a gripper 32 that is divided into a plurality of portions in the circumferential direction, and the inclined jacks 30 and 31 are extended to cause the gripper 32 to be crimped to the excavation wall 1. The excavator body B is supported and propelled downward.
[0031]
29 is a soil discharging means, which is composed of a soil discharge pipe 29a and a water supply pipe 29b. The lower end opening of the discharge pipe 29a faces the excavated earth and sand C gathered on the upper surface of the center of rotation of the cutter plate 12. The upper end opening at the lower end of the water supply pipe 29b refracted in a V-shape is connected to and communicated with the lower end of the earth discharge pipe 29a, so that the pressure water flowing upward from the lower end into the earth discharge pipe 29a is supplied from the water supply pipe 29b. The ejector action causes a suction force to be generated in the drainage pipe 29a to suck the excavated earth and sand C, and the earth and sand are discharged to a storage tank (not shown) installed at an appropriate upper position to separate the water and again. It is configured to be used as pressure water.
[0032]
The earth and sand once stored in the storage tank is carried out to the ground side by an appropriate carrying-out means. It should be noted that the scaffolding base 15 disposed on the column 14 so as to be movable up and down, the fixed base frame 20 and the top plate 23 fixed to the through hole 40 and the shaft T for passing through the carrying means. An air supply pipe or exhaust pipe insertion hole 41 for ventilation is provided.
[0033]
The method of excavating the shaft A with the shaft excavator thus configured and constructing the concrete lining 2 on the excavation wall surface 1 will be described. The shaft excavator presses the gripper 32 to the excavation wall surface 1 with inclined jacks 30 and 31. By causing the excavating wall surface 1 to take propulsion reaction force and to support the excavator body B, the inclined jack 31 that is inclined obliquely upward from the circular fixed frame 26 is extended to thereby extend the excavator body B. The rock surface of the face is cut down and excavated by the cutter plate 12 while propelling it vertically downward. The inclined jack 30 inclined obliquely downward from the circular fixed frame 26 adjusts the pressure-bonding force of the lower end portion of the gripper 32 against the excavation wall 1 to prevent the excavator body 10 from moving down more than necessary. It has a tensioning effect.
[0034]
The excavated earth and sand is scraped up to the back side of the cutter plate 12, that is, the upper surface side, through the slip-in opening 12b, and gathered on the rotation center of the cutter plate 12, and is collected on the ground by the earth discharging means 29 and the unloading means. To be discharged.
[0035]
As the shaft A is excavated by the excavator main body B, the column 14 standing upward from the excavator main body B also moves down integrally in the shaft A, and the wall surface excavated to the outer periphery of the lower end of the column 14 1 is exposed. While this shaft wall 1 is excavated by a mold 19 to a certain depth (length) that can be concrete-covered, an excavating blade 12a ′ is provided so as to be able to appear and retract on the outer periphery of the cutter plate 12. Is rotated in the radial direction from the outer periphery of the cutter plate 12, and the cutter plate 12 is rotated so that a part of the excavation wall surface 1 excavated by the cutter plate 12 is expanded in diameter by the excavation blade 12a '. The recessed part 3 which consists of the circumferential groove which excavated and continued in the circumferential direction of the excavation wall surface 1 is formed.
[0036]
The depth and the vertical width of the recess 3 are such that the length of the digging blade 12a ′ projecting from the outer periphery of the cutter plate 12 in the outer diameter direction, the thickness of the digging blade 12a ′, and the state where the digging blade 12a ′ is projected. It can be set according to the length of the cutter plate 12 to be dug. In addition, as this recessed part 3, without forming in the circumferential groove shape which continued to the annular | circular shape over the perimeter of the excavation wall surface 1, intermittently, ie, a discontinuous groove | channel, and the length direction of the excavation wall surface 1 and It may be formed by being provided at predetermined intervals in the circumferential direction, or may be formed in a continuous spiral groove. In addition, the operation of the jacks 30 and 31 of the gripper 32 during excavation of the shaft A by the cutter plate 12 without forming the recess 3 by the excavation blade 12a ′ protruding and descending in the radial direction from the outer periphery of the cata plate 12 The recess 3 may be formed by excavation with an excavating blade protruding from the cutter plate 12 by swinging the excavator body B with respect to the gripper 32.
[0037]
On the wall surface excavated by the cutter plate 12, a primary lining concrete layer 2A made of sprayed concrete is immediately applied using the scaffolding base 15 in order to prevent the wall surface from collapsing. When the vertical shaft A (excavation wall 1) is excavated, an operator rides on the scaffold base 15 that is arranged to be movable up and down on the lower half of the pillar 14 and moves the scaffold base 15 up and down along the pillar 14 As a result, the excavation wall surface 1 is inspected, the waterproof sheet 5 is stretched on the primary lining concrete layer 2A constructed on the excavation wall surface 1, and a reinforcing bar (not shown) is arranged.
[0038]
Further, when the excavator body B excavates a vertical shaft A having a length corresponding to the length of the movable mold 19 provided on the upper half side of the column 14, the movable mold suspended from the fixed base frame 20 is excavated. The frame 19 reaches a position where the upper end faces the lower end of the lining concrete 2 previously constructed on the waterproof sheet 5, and the chain block 21 that supports the formwork piece 19a is fixed to the fixed frame 20 The mold piece 19a is expanded in diameter by being moved toward the outer peripheral end side, and assembled into a cylindrical shape.
[0039]
By appropriately operating the chain block 21 and moving the movable mold frame 19 up and down, the upper mold surface 19 is aligned with the lower end of the lining concrete 2 previously constructed and is expanded in the outer diameter direction to move the movable mold frame 19. The lower end of the concrete supply pipe 25 is allowed to face the gap between the upper end of the wall and the excavation wall surface 1.
[0040]
On the other hand, on the lower half side of the support column 14, the scaffold base 15 is raised to the vicinity of the lower end portion of the movable mold frame 19, and the reinforcement is arranged in the gap between the movable mold frame 19 and the excavation wall surface 1 on the scaffold base. After mounting and fixing the wife formwork 19b, the concrete was put into the concrete hopper 24 installed on the top plate 23 fixed to the upper end of the support column 14, and the movable type was passed through the supply pipe 25. Concrete is placed in the gap between the frame 19 and the excavation wall surface 1 to construct a concrete lining 2 having a certain thickness to be a secondary lining concrete layer. As a result, a part of the placed concrete also fills the recess 3 formed on the excavation wall 1, and the outer peripheral surface of the concrete lining 2 has the same cross-sectional shape as the recess 3 and the recess 3. The convex part 4 in a state fitted and locked to is integrally formed. In addition, when the waterproof sheet 5 is stretched on the excavation wall surface 1, a lining structure in which the waterproof sheet 5 is interposed between the excavation wall surface 1 and the concrete lining 2 is obtained.
[0041]
In this way, after the lining concrete 2 is constructed so that the upper end portion is connected to the lower end of the previously applied lining concrete 2, the chain block 21 is moved by moving it inside the fixed base frame 20. The mold 19 is reduced in the inner diameter direction and folded to prepare for the next lining work.
[0042]
In the same manner, each time the shaft portion having a certain length having the concave portion 3 is excavated by the shaft excavator B, the concrete spraying work or the excavation wall surface using the scaffolding base 15 is performed on the lower half side of the column 14. In addition to performing inspection 1 and stretching work of the waterproof sheet 5 on the excavation wall 1, construction work of the lining concrete 2 using the movable mold 19 is performed in parallel on the upper half side of the column 14. . Note that the lining concrete 2 may be formed of an existing concrete panel provided with a convex portion that fits into the concave portion 3 on the outer surface without using cast concrete.
[0043]
【The invention's effect】
According to the concrete lining construction method for a shaft excavation wall according to the present invention, as described in claim 1 , every time the ground is excavated in a direct downward direction by a shaft excavator, the excavation wall surface After excavating a part in the direction of expanding the diameter, forming the excavation recess, assemble the mold along the excavation wall, and then place concrete between the mold and the excavation wall to cover the concrete. In parallel with the excavation of the shaft by the shaft excavator, it is characterized by forming a convex portion fitted and locked to the excavation recess by hardening of the concrete filled in the excavation recess. A recess having a desired cross-sectional shape can be formed on the wall surface of the shaft excavation, and concrete is placed in a formwork assembled along the excavation wall surface after excavation of the recess. A convex portion which is engaged with and supported in the recesses at the same time the outer peripheral surface of the concrete lining and construction of cleat lining can be reliably formed.
[0044]
Therefore, during the excavation of the shaft, the lower end of the built concrete lining is not supported at all and is facing the lower shaft excavator side. Since the convex portion formed on the outer peripheral surface is supported by the concave portion formed on the inner surface, there is no fear of sliding down to the shaft excavator side, and the safety of the work can be improved.
[0045]
Furthermore, according to the invention which concerns on Claim 2 , the said excavation recessed part is formed by projecting excavation blades, such as a disk cutter provided in the outer peripheral part of the cutter board of the said shaft excavator so that it can protrude and retract in radial direction. Therefore, a recess having a desired length and a desired depth can be formed continuously or intermittently in a desired portion of the shaft during excavation.
[0046]
In the concrete lining construction method described above, the invention according to claim 3 is that a pillar having a fixed height is erected upward at the center of the upper end of the shaft excavator, and the outer periphery of the upper half of the pillar is located outward. While a plurality of formwork pieces that can be expanded and contracted in the radial direction are arranged, a scaffolding base is arranged in the lower half part so as to be movable up and down. As a result, the shaft excavator can dig a certain length to a depth that allows the next concrete lining. Then, the mold piece is automatically lowered to the concrete lining position, and the concrete lining can be accurately and efficiently constructed by assembling the mold form by expanding the mold piece at this position. . In addition, since the scaffolding is arranged on the column so that it can move up and down, the scaffolding is lifted during concrete lining to inspect the excavation wall, stretch the waterproof sheet, and even into the formwork. The work of attaching the wife formwork to the bar arrangement or the lower end opening of the formwork can be performed smoothly and efficiently.
[Brief description of the drawings]
[FIG. 1] A longitudinal front view of a concrete lining,
[Fig.2] Simplified vertical side view of shaft excavator under construction of concrete lining,
FIG. 3 is a simplified plan view of the scaffolding part,
FIG. 4 is a simplified plan view of a fixed base frame portion.
[Explanation of symbols]
1 Excavation wall 2 Concrete lining 3 Concave 4 Convex
10 Excavator body
12 Cutter plate
12a 'drilling blade
14 Prop
15 Scaffolding stand
19 Mobile formwork A Vertical shaft B Excavator body

Claims (3)

  Each time the ground is excavated directly below by a shaft excavator, an excavation recess is formed in the excavation wall surface in a direction in which a part of the excavation wall surface is expanded, and then the formwork is formed along the excavation wall surface. And then projecting concrete between the formwork and the excavation wall to build a concrete lining, and fitting and locking into the excavation recess by hardening of the concrete filled in the excavation recess A method of constructing a concrete lining characterized by forming The shaft is excavated by rotating the cutter plate arranged at the lower end of the shaft excavator, and the excavating blade such as a disc cutter provided so as to be able to protrude and retract in the radial direction on the outer periphery of the cutter plate is projected. The method for constructing a concrete lining according to claim 1, wherein the excavation recess is formed by the method. A column with a fixed height is erected upward at the center of the upper end of the shaft excavator, and a plurality of mold pieces that can be expanded and contracted in the radial direction are disposed on the outer periphery of the upper half of the column. In addition, a scaffolding base is arranged in the lower half part so as to be movable up and down, and by expanding the above-mentioned formwork piece, assembling the formwork along the vertical excavation wall and using the scaffolding base to place the work in the formwork The concrete lining construction method according to claim 1, wherein the concrete lining is performed.

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