JP3897536B2 - Receiving frame for waterproofing sheet for segment covering in tunnel machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a receiving frame for winding up a waterproof sheet that covers a segment and prevents entry of groundwater or the like into the tunnel when the tunnel excavated by a tunnel excavator is covered with a segment. .
[0002]
[Prior art]
When tunnel lining is performed by assembling segments into a tunnel excavated by a tunnel excavator, groundwater often enters the tunnel from the joint between the segments. In this case, a water-stop seal is attached to the joint between the segments. However, when an opening occurs in the joint due to a construction error of the segment lining, a sufficient sealing effect cannot be exhibited.
[0003]
For this reason, a technique has been developed in which the outer peripheral surface of a segment is covered with a waterproof sheet made of a synthetic resin such as polyethylene to improve the water stoppage of a joint portion between segments. That is, a belt-shaped waterproof sheet (hereinafter referred to as a new waterproof sheet) is placed in the tail plate of a tunnel machine, and a rear end portion is provided at the front end of a waterproof sheet (hereinafter referred to as an existing waterproof sheet) wound up in a cylindrical shape. A cylindrical waterproof sheet is formed by winding up a predetermined width of the cylindrical sheet while polymerizing and heat-sealing the overlapping portion at the opposite end of the waterproof sheet with a self-propelled welding machine or the like. The segments are assembled by covering the segments with a cylindrical waterproof sheet. The segment covered with the tubular waterproof sheet is relatively sent to the tunnel excavation wall surface side with the excavation of the tunnel excavator.
[0004]
[Problems to be solved by the invention]
However, since the waterproof sheet is made of a synthetic resin sheet that is flexible and has an appropriate stretchability, when it is rolled up in a cylindrical shape, wrinkles, wavy irregularities, or dripping is likely to occur. It is difficult to heat-weld the overlapping portion with the sheet uniformly.
[0005]
For this reason, a cylindrical waterproof sheet receiving frame is arranged movably back and forth along the inner peripheral surface of the tail plate of the tunnel machine, and a belt-shaped waterproof sheet is disposed on the inner peripheral surface of the receiving frame at the front end of the existing waterproof sheet. A new waterproof sheet in the form of a cylinder is formed by pressing it against the receiving frame while being overlapped with a predetermined width on the part and winding it up in a single roll, and a welder between the opposing surfaces in the overlapping part of the newly installed waterproof sheet and the existing waterproof sheet The opposite surface of these waterproof sheets is melted by inserting and moving in the circumferential direction, and the newly installed waterproof sheet is pressed from the inner peripheral surface side by a pressing roller that moves integrally after the electric iron. The facing surfaces of both waterproof sheets that are separated when the waterproof sheet is melted by an electric iron are polymerized and welded, but the receiving frame is made of steel or iron with high thermal conductivity. As a result, the heat of the electric iron escapes to the receiving frame and the waterproof sheet is insufficiently melted, and furthermore, the temperature drops rapidly after welding, resulting in poor welding, and groundwater may enter from the poorly welded location. There is a problem that occurs.
[0006]
The present invention has been made in view of such problems, and the object of the present invention is to provide heat to the receiving frame when the overlapping portion of the existing waterproof sheet and the newly installed waterproof sheet is welded by the welding device. It is an object of the present invention to provide a structure of a receiving frame for a segment covering waterproof sheet in a tunnel excavator capable of thermally welding the superposed portion at a predetermined melting temperature while preventing escape.
[0007]
[Means for Solving the Problems]
To achieve the above object, the receiving frame for the segment covering waterproof sheet in the tunnel machine of the present invention is a metal receiving frame arranged along the inner peripheral surface of the tail plate as described in claim 1. And a winding device that winds in a cylindrical shape while superposing the rear end portion on the front end portion of the waterproof sheet in which the strip-shaped waterproof sheet for covering the segment is first wound in contact with the inner peripheral surface of the receiving frame, and these In a tunnel excavator provided with a welding device that welds the overlapping portions of the waterproof sheet integrally, a heat insulating layer is layered on the inner peripheral surface of the receiving frame.
[0008]
The invention according to claim 2 is a receiving frame having a structure different from that of the receiving frame, wherein the receiving frame is provided with heat generating means. A heating wire can be used as the heating means.
[0009]
[Action]
A belt-shaped waterproof sheet having a constant width is drawn out in the circumferential direction on the inner side of a metal receiving frame disposed along the inner peripheral surface of the tail plate, and in contact with the inner peripheral surface of the receiving frame by a winding device. Wind it up in a shape. At this time, the newly formed waterproof sheet is formed by winding up the tubular waterproof sheet on the front end of the previously wound cylindrical waterproof sheet while winding up the opposite end of the belt-shaped waterproof sheet to form a new waterproof sheet. Is pressed against the inner peripheral surface of the receiving frame by appropriate fixing means.
[0010]
The welded integration of the above-mentioned overlapping portion between the newly installed waterproof sheet and the existing waterproof sheet is performed between the opposing ends of the overlapping portion of the newly installed waterproof sheet and the existing waterproof sheet, that is, the inner peripheral surface of the front end portion of the existing waterproof sheet and the inner periphery of this end portion. Insert the welding iron of the welding device between the rear end outer peripheral surface of the newly installed waterproof sheet stacked on the surface, and move the welding iron in the circumferential direction so that the opposing surface of the newly installed waterproof sheet and the existing waterproof sheet is It is performed by melting and polymerizing the opposing surfaces after passing through the welding iron. At this time, since the heat insulating layer is layered on the inner peripheral surface of the receiving frame receiving the cylindrical waterproof sheet, the heat of the welding iron escapes to the metal receiving frame side by the heat insulating layer. Prevents and prevents the newly installed waterproof sheet from being welded and connected to the existing waterproof sheet without causing defective welds by reliably and efficiently heating and melting the facing surfaces of the overlapping portion of the newly installed waterproof sheet and the existing waterproof sheet. be able to.
[0011]
In addition to preventing the heat of the welding iron from escaping to the receiving frame side by the heat insulating layer, a heat generating means may be provided on the metal receiving frame as described in claim 2. In this case, since the receiving frame is heated by the heating means, when the overlapping portion of the newly installed waterproof sheet and the existing waterproof sheet is melted by the welding iron of the welding apparatus as described above, the high temperature heat for melting generated from the welding iron is generated. The superposed part can be welded and integrated by acting on the end facing surface of the superposed part of the newly installed waterproof sheet and the existing waterproof sheet in a concentrated manner with almost no escape to the receiving frame side. It is prevented from being rapidly cooled by being kept warm by the heat from the receiving frame, and can be gradually cooled so that reliable welding and integration of the newly installed waterproof sheet and the existing waterproof sheet can be performed.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Next, specific embodiments of the present invention will be described with reference to the drawings. In FIG. 1, reference numeral 1 denotes a tunnel excavator, and a movable frame 3 movable in the front-rear direction is disposed in the tail plate 2 of the tunnel excavator 1, and the tail plate of the tail plate 2 is disposed on the movable frame 3. A cylindrical steel receiving frame 4 disposed along the inner peripheral surface, and a strip-shaped waterproof sheet 5 for covering the segment in a cylindrical shape in contact with the inner peripheral surface of the receiving frame 4 to form a new waterproof sheet 5A The winding device 6 to be formed, the welding device 7 for welding and integrating the overlapping portion 5C of the existing waterproof sheet 5B previously wound in a cylindrical shape and the new waterproof sheet 5A, and the fixing means 8 for the new waterproof sheet 5A And fixing means 9 for the existing waterproof sheet 5B.
[0013]
The movable frame 3 is supported by a fixed frame 10 fixed at a suitable position on the inner peripheral surface of the tail plate 2 so as to be movable back and forth. Specifically, the fixed frame 10 has an annular fixed frame portion 10a in which the outer peripheral end is integrally fixed to the inner peripheral surface of the tail plate 2, and the inner peripheral end of the fixed frame portion 10a toward the rear. On the other hand, the movable frame 3 cannot be rotated in the circumferential direction on the outer peripheral surface of the fixed cylindrical portion 10b, and is slidable only in the front-rear direction. The support cylinder part 3a fitted and a ring-shaped vertical support frame part 3b whose inner peripheral end is integrally fixed to the front end of the support cylinder part 3a. The steel is formed on the outer peripheral end of the vertical support frame part 3b. A front end of the made receiving frame 4 is fixed integrally, and the receiving frame 4 is provided in a projecting manner in the outer periphery of the supporting cylinder part 3a of the movable frame 3 in a horizontal direction parallel to the supporting cylinder part 3a. The longitudinal movement of the movable frame 3 is performed by a moving jack 20 fixed to the fixed frame portion 10a.
[0014]
As shown in FIG. 2, the steel receiving frame 4 has a heat insulating layer 4A having a constant thickness formed on the inner peripheral surface of the inner peripheral surface for supporting the waterproof sheet 5 with a smooth surface. Layered. This heat insulating layer 4A is extremely lower in thermal conductivity than the steel plate forming the receiving frame 4, and is in a cylindrical shape in contact with the inner peripheral surface of the receiving frame 4 without causing wrinkles or waves in the waterproof sheet 5. What is necessary is just to form from the material which the surface which can wind up is smooth and has moderate hardness. For example, the heat insulating layer 4A may be formed from a synthetic resin such as nylon, polyethylene, polyester, polypropylene, rubber, synthetic rubber, or a wooden board.
[0015]
Further, as shown in FIG. 3, a pair of front and rear ring-shaped support frames 11a, 11b, and 12a with a small space in the front and rear of the outer peripheral surface front and rear end portions of the support cylinder portion 3a in the movable frame 3; 12b are fixed in an upright state, and a first swiveling ring 13 rotatably disposed by a plurality of rollers (not shown) is disposed between the outer peripheral portions of the front support frames 11a and 11b. The first swivel ring 13 is configured to be rotated in the circumferential direction at a position at a small interval inward from the inner peripheral surface of the front end portion of the frame 4.
[0016]
The hoisting device 6 projects from the first swiveling ring 13 and an appropriate rear surface of the first swiveling ring 13 in a rearward direction in parallel with the length direction of the receiving frame 4 as shown in FIG. And a plurality of chuck fittings 15 attached to the winding arm 14 at regular intervals in the length direction. A belt-like belt having a constant width drawn by the chuck fitting 15 is formed. The waterproof sheet 5 is wound around a winding core, and the front end of the winding core of the winding roll 16 is supported at an appropriate position on the rear surface of the frame portion 10 a of the fixed frame 10 to receive the winding roll 16 and the inner peripheral surface of the frame 4. Are fixedly arranged at predetermined positions with a small gap therebetween, and the end of the belt-shaped waterproof sheet 5 is gripped by the chuck metal fitting 15 and pulled out in the circumferential direction.
[0017]
On the other hand, a second swiveling ring 17 rotatably disposed by a plurality of rollers (not shown) is disposed between the outer peripheral portions of the rear support frames 12a and 12b. The frame 4 is configured to rotate in a circumferential direction at a position at a small interval inward from the inner peripheral surface of the rear end of the frame 4, and a welding device 7 is attached to the second swivel ring 17 as shown in FIG. ing. This welding device 7 is composed of an electric heating iron 7A and a pressing roller 7B attached to a fixed plate 18 fixed at a suitable position on the outer peripheral portion of the second swivel ring 17, and the electric heating iron 7A is an existing waterproof rolled up in a cylindrical shape. Inserted between the inner peripheral surface of the front end portion of the sheet 5B and the outer peripheral surface of the rear end portion of the newly installed waterproof sheet 5A superposed on the inner peripheral surface of the front end portion to melt these opposing surfaces. The facing surface of the overlapping portion 5C between the newly installed waterproof sheet 5A and the existing waterproof sheet 5B, which are separated by insertion of the iron 7A, is melted by the electrothermal iron 7A, and then joined and integrated with a constant pressure force.
[0018]
The drive means for the first and second swivel rings 13 and 17 are provided with drive motors 21 and 22 on the front and rear portions of the support tube portion 3a of the movable frame 3 as shown in FIG. The pinions 23 and 24 fixed to the rotary shafts 22 and 22 are meshed with the internal gears 25 and 26 formed on the inner peripheral surfaces of the first and second swivel rings 13 and 17, and are driven by the drive motors 21 and 22. Each swivel ring 13, 17 is configured to swivel.
[0019]
The new waterproof sheet 5A wound in a cylindrical shape in contact with the inner peripheral surface of the heat insulating layer 4A layered on the receiving frame 4 is held in a state of being pressed against the receiving frame 4 by the fixing means 8. As shown in FIG. 5 and the left half of FIG. 5, the fixing means 8 is composed of a plurality of pressing jacks 8 </ b> A fixed to the outer peripheral surface of the support cylinder portion 3 a of the movable frame 3 at small intervals in the circumferential direction. The portion of the inner peripheral surface of the newly installed waterproof sheet 5A, excluding the overlapping portion 5C with the existing waterproof sheet 5B, is pressed against the inner peripheral surface of the frame 4 at the tip of the piston rod of the pressing jack 8A and hangs on the newly installed waterproof sheet 5A The pressing member 8B is fixed so as not to cause such as.
[0020]
On the other hand, the fixing means 9 for fixing the front end portion of the existing waterproof sheet 5B is a plurality of pieces fixed to the outer peripheral surface of the rear end portion of the movable frame 3 at small intervals in the circumferential direction as shown in the right half portion of FIG. The pressure jack 9A is composed of a plurality of pressing jacks 9A, and the front end of the existing waterproof sheet 5B is received at the front end of the piston rod of the pressing jack 9A and pressed against the inner peripheral surface of the rear end of the frame 4 to hang on the end of the existing waterproof sheet 5B. The pressing member 9B is fixed so as not to cause the.
[0021]
Next, the operation of each device and means will be described. First, as shown in FIGS. 1 and 7, the moving jack 20 attached to the fixed frame portion 10a of the fixed frame 10 is contracted to house the movable frame 3 in the fixed frame 10, and the movable frame 3 In the rear, the existing waterproofing is made by first winding the front half of the outer peripheral surface of the segment 19 already assembled into a cylindrical shape by an erector (not shown) along the inner peripheral surface of the tail plate 2 in the rear end portion of the tail plate 2. The rear end of the receiving frame 4 is covered with the rear half of the sheet 5B, and the front end of the existing waterproof sheet 5B protruding from the segment 19 is tensioned by the pressing member 9B of the fixing means 9 without dripping or wrinkling. The shield jack 27 is pressed against the inner peripheral surface of the end portion, and the spreader 27a at the tip of the rod is pressed against the front end surface of the segment 19 through the notch provided in the vertical support frame portion 3b of the movable frame 3.
[0022]
In this state, as shown in FIG. 4, the tip of the winding roll 16 of the strip-shaped waterproof sheet 5 supported in a cantilever manner on the fixed frame 10 side is supported in a cantilever manner on the first swivel ring 13. When the first swiveling ring 13 is swung after being gripped by the chuck metal fitting 15 attached to the hoisting arm 14, the hoisting arm 14 moves in the circumferential direction along the inner peripheral surface of the receiving frame 4, While pulling the belt-shaped waterproof sheet 5 wound around the winding roll 16 from the winding roll 16 in the circumferential direction, the waterproof sheet 5 is wound up in a cylindrical shape on the inner peripheral surface of the frame 4 and newly installed waterproof sheet 5A. Form.
[0023]
At this time, the outer peripheral surface of the rear end portion of the newly installed waterproof sheet 5A is overlapped by a predetermined width on the inner peripheral surface of the front end portion of the existing waterproof sheet 5B received on the inner peripheral surface of the rear end portion of the frame 4, and the overlapping portion 5C Is pressed against the inner peripheral surface of the rear end portion of the receiving frame 4 by the pressing member 9B of the fixing means 9, and the inner periphery of the receiving frame 4 is prevented while the new waterproof sheet 5A is prevented from dripping by the pressing member 8B of the fixing means 8. After being pressed against the surface and forming the new waterproof sheet 5A, the winding roll 16 is removed.
[0024]
Next, the overlapping means 5C of the newly installed waterproof sheet 5A and the existing waterproof sheet 5B is unfastened by the fixing means 9 that is pressed against the inner peripheral surface of the frame 4, and the electric iron 7A of the welding device 7 is connected to the newly installed waterproof sheet 5A. Inserted as shown in FIG. 2 in the overlapping portion 5C with the existing waterproof sheet 5B, that is, between the outer peripheral surface of the rear end portion of the new waterproof sheet 5A and the inner peripheral surface of the front end portion of the existing waterproof sheet 5B, the second swivel ring By rotating 17, the electrothermal iron 7 A is moved in the circumferential direction to separate and overlap the overlapping portion 5 C between the newly installed waterproof sheet 5 A and the existing waterproof sheet 5 B, thereby heating and melting the facing surfaces.
[0025]
When the sheet is melted by the electric heating iron 7A, the heat insulating layer 4A is provided on the inner peripheral surface of the steel receiving frame 4 that receives the overlapping portion 5C of the newly installed waterproof sheet 5A and the existing waterproof sheet 5B as described above. The heat insulating layer 4A prevents heat from the electric heating iron 7A side from being transmitted to the steel receiving frame 4 and efficiently transmits it to the opposing surface of the newly installed waterproof sheet 5A and the existing waterproof sheet 5B. The opposing surface can be melted reliably and smoothly.
[0026]
Further, following the movement of the electric heating iron 7A, the inner periphery of the new waterproof sheet 5A on the opposite surface between the newly installed waterproof sheet 5A and the existing waterproof sheet 5B immediately after the pressing roller 7B moves together with the electric heating iron 7A. The surface is pressed against the existing waterproof sheet 5B side, and the sheet facing surface melted by the electric heating iron 7A is polymerized again, and is surely welded completely without causing wrinkles. The overlapping portion 5C of the newly installed waterproof sheet 5A and the existing waterproof sheet 5B is pressed by the pressing member 9B of the fixing means 9.
[0027]
The formation process of the newly installed waterproof sheet 5A wound around the inner peripheral surface of the receiving frame 4, and the welding process of the overlapping portion 5C of the newly installed waterproof sheet 5A and the existing waterproof sheet 5B by the welding apparatus 7 after the formation of the newly installed waterproof sheet 5A, In order to shorten the tunnel construction time, it is performed in parallel with the tunnel excavating machine 1. That is, the shield jack 27 of the tunnel digging machine 1 is extended and digging while taking the propulsion reaction force by the segment 19, and at the same time, the moving jack 20 is extended at the same speed to move from the fixed frame 10 as shown in FIG. The frame 3 is pushed backward.
[0028]
After the tunnel excavator 1 has excavated for a certain length, the shield jack 27 is contracted and the pressing means 8B and 9B of the fixing means 8 and 9 are released from the inner peripheral surface of the newly installed waterproof sheet 5A and the overlapping portion 5C. After that, the movable frame 3 provided with the winding device 6, the welding device 7 and the like is housed in the fixed frame 10 by contracting the moving jack 20.
[0029]
Then, a space part in which the segment 19 can be assembled is provided in the newly installed waterproof sheet 5A. In this space part, a new segment 19 is connected to the inner peripheral surface of the front half part of the existing waterproof sheet 5B protruding from the existing segment 19 and the newly installed waterproof sheet. Assemble along the inner peripheral surfaces of these waterproof sheets across the inner peripheral surface of the rear half of the sheet 5A. At this time, the inner peripheral surface of the front end portion of the new waterproof sheet 5A is pressed by the pressing member 9B of the fixing means 9 of the existing waterproof sheet 5B provided at the rear end portion of the movable frame 3 so that the new waterproof sheet 5A does not sag. The waterproof sheet winding roll 16 is set.
[0030]
After the segment 19 is assembled, the shield jack 27 is extended to contact the front end surface of the new segment 19 and further extended to take the reaction force on the new segment 19 and excavate the tunnel excavator 1, and at the same time the tunnel excavator As described above, the moving jack 20 is extended at the same speed to push the movable frame 3 backward from the fixed frame 10 as described above. Winding work of the newly installed waterproof sheet 5A on the inner peripheral surface of the receiving frame 4 by the device 6, and welding work of the overlapping portion of the newly installed waterproof sheet 5A and the previously wound waterproof sheet 5B by the welding device 7 after winding. The assembly work of the segments 19 is sequentially performed.
[0031]
In the above embodiment, in order to prevent the heat from the electric heating iron 7A from escaping to the receiving frame 4 side at the time of welding the overlapping portion 5C of the newly installed waterproof sheet 5A and the existing waterproof sheet 5B by the electric heating iron 7A, the receiving frame Although the heat insulating layer 4A is deposited on the inner peripheral surface of the heat generating layer 4, the heat generated from the heating wire is formed on the inner peripheral surface of the receiving frame 4 as shown in FIG. The means 4B is arranged in a spiral shape, and the heat generating means 4B is covered with a metal coating layer 4b having a smooth inner peripheral surface, and a new waterproof sheet 5A and an existing waterproof sheet are formed by an electric heating iron 7A. The heat generating means 4B heats the receiving frame 4 when the overlapping portion 5C is welded to 5B, and the heating temperature prevents the heat from the electric heating iron 7A from escaping to the receiving frame 4 side, and the overlapping overlapping portion after welding Configure to prevent cooling It can have. Since the other structure is the same as that of the said Example, the same code | symbol is attached | subjected to the same part and detailed description is abbreviate | omitted. In any of the above embodiments, the receiving frame 4 is made of steel, but may be formed of iron or other appropriate hard metal plate.
[0032]
【The invention's effect】
As described above, according to the first aspect of the present invention, the metal receiving frame disposed along the inner peripheral surface of the tail plate, and the strip-shaped waterproof sheet for covering the segment in contact with the inner peripheral surface of the receiving frame. Tunneling machine provided with a winding device that winds the rear end of the waterproof sheet rolled up in a cylindrical shape while superimposing the rear end on the front end of the waterproof sheet, and a welding device that welds the overlapping portions of these waterproof sheets together In this case, a heat insulating layer is layered on the inner peripheral surface of the receiving frame, so that the heat of the welding apparatus for welding the overlapping portion of the newly installed waterproof sheet and the existing waterproof sheet is made of metal by the heat insulating layer. Can be reliably prevented from escaping to the receiving frame side, and therefore, the facing surface of the overlapping portion of the newly installed waterproof sheet and the existing waterproof sheet is reliably and efficiently heated and melted, resulting in poorly welded portions. Gastric new tarpaulin may be a connection structure between the existing waterproofing sheet, groundwater can be prevented from entering from the joint segments in the tunnel.
[0033]
According to the invention of claim 2, since the heat generating means such as a heating wire is provided in the receiving frame in place of the heat insulating layer, the overlapping portion of the newly installed waterproof sheet and the existing waterproof sheet is formed by the welding device. When heating and melting, the receiving frame is heated by a heating means to receive the high-temperature heat for melting emitted from the welding iron so that it hardly acts on the frame side and acts intensively on the above-described overlapping portion. It can be welded and integrated reliably and smoothly, and the welded overlapping part is kept warm by the heat from the receiving frame to prevent rapid cooling. Welding integration is possible.
[Brief description of the drawings]
FIG. 1 is a simplified longitudinal side view of an entire tunnel excavator,
FIG. 2 is an enlarged longitudinal front view of a receiving frame portion where welding is performed,
FIG. 3 is a simplified longitudinal side view of a movable frame portion equipped with a winding device and a welding device;
FIG. 4 is a perspective view of a winding device portion;
FIG. 5 is a simplified longitudinal front view of a tail plate portion equipped with fixing means;
FIG. 6 is a simplified vertical side view of a movable frame portion equipped with fixing means;
FIG. 7 is a simplified vertical side view of a state in which a movable frame is housed in a fixed frame;
FIG. 8 is a simplified longitudinal side view of the movable frame pushed out from the fixed frame;
FIG. 9 is a partial enlarged vertical front view showing another structure of the receiving frame.
[Explanation of symbols]
1 Tunneling machine 2 Tail plate 3 Movable frame 4 Receiving frame
4A Thermal insulation layer 5 Tarpaulin
5A new tarpaulin
5B Existing tarpaulin
5C Superposition part 6 Winding device 7 Welding device 8, 9 Fixing means
10 Fixed frame

Claims (3)

A metal receiving frame disposed along the inner peripheral surface of the tail plate, and a rear end at the front end portion of the waterproof sheet in which the strip-shaped waterproof sheet for covering the segment is wound up in contact with the inner peripheral surface of the receiving frame. In a tunnel excavator provided with a winding device that winds a cylindrical portion while polymerizing the portions and a welding device that welds the overlapping portions of these waterproof sheets together, a heat insulating layer is formed on the inner peripheral surface of the receiving frame. A receiving frame for a waterproof sheet for covering a segment in a tunnel machine characterized by being worn. A metal receiving frame disposed along the inner peripheral surface of the tail plate, and a rear end at the front end portion of the waterproof sheet in which the strip-shaped waterproof sheet for covering the segment is wound up in contact with the inner peripheral surface of the receiving frame. In a tunnel excavator provided with a winding device that winds up a cylindrical portion while polymerizing the portions and a welding device that welds the overlapping portions of these waterproof sheets together, heat generating means is disposed on the receiving frame. A receiving frame for a waterproof sheet for covering a segment in a tunnel digging machine. The receiving frame for a waterproof sheet for covering segments in a tunnel machine according to claim 2, wherein the heat generating means is a heating wire.

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