JP2645407B2 - Seal structure at the start port and seal structure at the arrival port - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a shield excavator for constructing tunnels and pipelines, and a starting port of a shaft provided for propelling a pipe buried underground. The present invention relates to a sealing structure of an arrival port.

(Problems to be Solved by the Prior Art and the Invention) When a shield excavator or a burial pipe (hereinafter, referred to as a hollow body in this section) is propelled from a starting port of a starting shaft, excavated soil and groundwater are discharged from the starting port. Conventionally, the seal structure shown in FIGS. 5a and 5b is applied to a pit wall 102 provided with a start-up port 100, and the propelled hollow body reaches To prevent inflow of excavated sediment and groundwater when entering the shaft from its arrival port,
The seal structure shown in FIG. 6 is used.

In the seal structure of the launch port, an annular elastic seal member 106 having a circular hole 106a having a smaller diameter than the outer diameter of the hollow body 104 is disposed coaxially with the launch port 100, and the seal member 106 in the traveling direction of the hollow body is formed. At the rear, a plurality of metal fittings 108 made of a rectangular metal plate are arranged around the starting port 100 at intervals. The sealing material 106 and the metal fitting 108 are connected to the anchor bolt 110
And is fixed to the pit wall 102 by a fixing tool such as a nut 112 screwed to the anchor bolt, and a metal fitting 108 is provided with a long hole through which the anchor bolt 110 partially embedded in the pit wall penetrates. I have.

When the propulsion of the hollow body 104 from the starting shaft starts,
As shown by the imaginary line in FIG. 5b, the peripheral portion (inner peripheral portion) of the hole 106a of the sealing material through which the hollow body 104 passes is bent forward in the propulsion direction, and the inner peripheral portion contacts the outer peripheral surface of the hollow body 104. Touch As a result, the space between the hollow body 104 and the wall surface that defines the starting port 100 is sealed, and the inflow of excavated earth and sand, groundwater, and the like from the starting port 100 into the shaft is prevented.

A large earth pressure due to the excavated earth and sand, the groundwater, etc. acts on the sealing material 106, and this fluctuates every moment.
In order to maintain the sealing material 106 against the earth pressure,
Each metal fitting is moved until its tip comes into contact with the hollow body 104, and supports the sealing material 106 at the rear.

The sealing structure of the reaching port 118 provided on the shaft 116 of the reaching shaft shown in FIG. 6 is composed of the same elements as those of the sealing structure of the starting port, and the elements are symmetrical with those at the starting port. Are arranged.

When the hollow body 104 reaches the reaching shaft through the arrival port 118 and the hole 106a of the sealing material, the inner peripheral edge of the sealing material 106 is bent in the traveling direction of the hollow body 104, and closely contacts the peripheral surface of the hollow body 104. The space between the hollow body and the sealing material 106 is sealed.

By the way, in the sealing structure of the starting port, the sealing material 106 is used.
The action direction of the force of the hollow body 104 and the action direction of the earth water pressure exerted on the peripheral edge portion are opposite to each other, while the action direction is the same in the seal structure of the arrival port. For this reason, the excavated earth and sand, groundwater, and the like easily pass between the inner peripheral edge of the sealing material 106 at the arrival port and the hollow body 104 in contact with the hole while expanding the hole, and easily flow into the arrival shaft. In order to prevent this, immediately after the hollow body 104 arrives at the arrival shaft, each metal fitting 108 is moved until the tip end thereof comes into contact with the inner peripheral edge of the sealing material 106, whereby the inner peripheral edge, the hollow body 104 and Maintain close contact between

However, in both the starting port and the arrival port, the movement of each bracket must be performed by beating them all at once, which requires not only a large number of people but also a delay in the movement of each bracket. May cause incomplete sealing of the starting port and the arrival port. Furthermore, the excavated earth and groundwater may erupt into the shaft at a high pressure due to unexpected large fluctuations in the soil pressure.

It is an object of the present invention to ensure the sealing of the launch and destination ports without manual intervention.

(Means for Solving the Problems) The seal structure of the launch port has a hole that is disposed opposite to the arrival port and that allows penetration of a hollow body such as a shield excavator, a lining, and a burial pipe, An elastic sealing member having a peripheral portion defining a hole that can be in close contact with the hollow body; and a plurality of metal fittings disposed behind the sealing material in a propulsion direction and spaced from each other around the hole of the sealing material. And a fixture for fixing the fitting and the sealing material to the pit wall,
Each metal fitting is fixed to the pit wall by the fixing tool, and is attached to the first plate via a spring steel plate facing the sealing material, and is attached to the first plate and faces the sealing material. And a second plate extending toward the side of the hole of the sealing material, the second plate being capable of contacting the outer peripheral surface of the hollow body at a tip end thereof (claim 1).

It is preferable that a stopper is provided on the second plate so as to be in contact with a rear surface of the first plate (claim 2). The first and second plates can be butted against each other and the spring steel plate can be fixed to the front surfaces of both plates (claim 3).

In addition, the sealing structure of the arrival port has a hole that is disposed to face the arrival port and allows the hollow body to pass therethrough, and a peripheral edge portion that defines the hole is an elastic sealing material that can be in close contact with the hollow body. And a plurality of metal fittings in front of the sealing material with respect to the propulsion direction and spaced apart from each other around the hole, and a fixture for fixing the sealing material and the metal fitting to the downhole wall, A first plate fixed to the pit wall by the fixture and facing the sealing material;
A second plate attached to the first plate via a spring steel plate facing the seal member and extending toward the hole side of the seal member relative to the seal member (claim 4). In this sealing structure, it is preferable that the second plate is provided with a stopper that can abut on a rear surface of the first plate (claim 5). In addition, a cable for sequentially connecting the second plate so as to be relatively movable with respect to the plate, and both ends of the cable are fixed to the hole wall or a shoring installed to maintain the vertical shaft. It is preferable to provide a cable (claim 6). Further, it is preferable that both the stopper and the cable are provided (claim 7).

In another sealing structure of the reaching port, each metal fitting swings on the second plate via another spring steel plate in addition to the first plate, the second plate and the spring steel plate connecting these plates. A third plate is movably mounted and can contact the peripheral portion of the hole of the sealing material. In this sealing structure, a stopper attached to the second plate and capable of abutting on the front surface of the first plate, and abutting on a front surface of the second plate attached to the third plate. It is preferable to provide a possible stopper (claim 9). Also, the second
Connecting the third plate and the third plate,
It is preferable to provide a rope similar to that described above.
0). Furthermore, it is preferable that both stoppers and both cords are provided (claim 11).

According to the first aspect of the present invention, the second plate forming a part of the seal structure of the starting port is a hollow body, that is, an outer peripheral surface of a propelled shield body or a non-propelled lining. When it comes into contact with the outer peripheral surface of the pipe or the outer peripheral surface of the pipe to be propelled, the seal member is swung with respect to the first plate by the elastic bending of the spring steel plate, and the sealing material that comes into close contact with the outer peripheral surface of the hollow body is moved backward. Support with. In the case of a shield machine in which a backing material injection pipe extending in the axial direction is attached to the outer peripheral surface of the shield body, when the second plate contacts the backing material injection pipe, the second The plate is
When the spring steel plate is rocked by elastic bending, the spring steel plate is simultaneously rocked in the other direction by the twist of the spring steel plate around a line perpendicular to the bending line. as a result,
The second plate tilts so as to contact a side surface of the backing material injection tube (a surface between a top surface of the backing material injection tube and an outer peripheral surface of the shield body), and the second plate As compared with the case where the sealing material is in contact with the top surface of the backing material injecting tube, a gap generated between the sealing material and the outer peripheral surface of the shield main body is reduced, whereby the sealing material and the shield main body are Sealing between the two can be improved. For this reason, the bend in the opposite direction due to the action of soil water pressure at the peripheral edge of the hole of the sealing material is prevented, and the starting port is securely sealed without any human intervention.

According to the second aspect of the present invention, when the hollow body is eccentric and the tip of the second plate cannot contact the outer peripheral surface of the hollow body, a stopper is provided on the rear surface of the first plate. Stops the rotation of the second plate. For this reason, in this case as well, the bending in the reverse direction due to the action of the soil water pressure at the peripheral portion of the hole of the sealing material is prevented without manual intervention, and a reliable sealed state is maintained.

According to the third aspect of the invention, the second plate can be swung only forward in the propulsion direction without providing the stopper, and can be prevented from swinging rearward.

According to the invention described in claim 4, when the hollow body reaches the reaching shaft through the arrival port and the hole of the sealing material, the peripheral edge (inner peripheral edge) of the hole of the sealing material is propelled. The second plate is pivoted against the spring force of the spring steel plate. When the hollow body is formed of a shield machine in which a backing material injection tube extending in the axial direction is attached to the outer peripheral surface of the shield body, when the backing material injection tube hits the sealing material, The second plate is swung in the other direction by the twist of the spring steel plate. As a result, the second plate tilts, and the sealing material is pressed against the side surface of the backing material injection tube. The spring biasing force of the steel plate generated by the swinging of the second plate acts to prevent the seal member subjected to the earth pressure from expanding its hole. Therefore, according to the present invention, the access port is securely sealed without manual intervention, and the inflow of excavated earth and sand, groundwater, and the like into the access shaft is prevented.

According to the fifth aspect of the present invention, the hole of the sealing material is further expanded due to, for example, an unexpected sudden rise of the soil water pressure, and the second plate further swings accordingly. In other words, when the support of the sealing material by the spring biasing force of the spring steel plate is insufficient, the swinging of the second plate causes the stopper that swings together with the stopper to abut on the first plate. Is stopped by Also,
According to the invention described in claim 6, when the support of the sealing material by the spring biasing force of the spring steel plate becomes insufficient, the swing of the second plate is limited within the range of extension of the rope. In addition, the opening of the hole of the sealing material can be suppressed. Further, according to the seventh aspect of the present invention, by using both the rope and the stopper, it is possible to suppress the expansion of the hole of the sealing material and further completely prevent the expansion. Also in these cases, reliable sealing of the reaching port is automatically maintained, and the inflow of the excavated earth and sand or groundwater into the reaching shaft can be prevented.

According to the invention described in claim 8, when the peripheral portion of the hole of the sealing material is bent with the arrival of the hollow body at the reaching shaft, the second and the metal fittings located in front of the sealing material are bent. The third plate swings relative to the first plate and the second plate against the spring force of the spring steel plate. According to the present invention, the bent peripheral edge contacting the hollow body is pressed against the hollow body by the third plate contacting the hollow body due to the spring biasing force of the spring steel plate acting on the third plate. When a backing material injecting tube extending in the axial direction is attached to the outer peripheral surface of the shield main body, when the backing material injecting tube hits the sealing material, the spring plate is elastically twisted. The third plate is swung in yet another direction. As a result, the third plate tilts,
The sealing material is pressed against the side surface of the backing material injection tube. As a result, more reliable sealing at the arrival port is achieved.

According to the ninth aspect of the present invention, the stoppers attached to the second and third plates abut against the first and second plates, respectively, so that the second and third plates become excessively large. Swing can be prevented. From this, it is possible to reliably support the seal member which receives an excessive earth pressure, which cannot be sufficiently supported only by the spring biasing force exerted by each spring steel plate.
According to the tenth aspect of the present invention, the range of swinging of the second and third plates accompanying the elastic deformation of the sealing material is suppressed within an allowable range of the elongation of the rope. A sealing material can be supported. Further, according to the eleventh aspect of the present invention, by using both the rope and the stopper, it is possible to suppress the expansion of the hole of the sealing material and prevent the expansion of the hole. Also in these cases,
Reliable sealing of the reaching port is automatically maintained, and the inflow of the excavated sediment and groundwater into the reaching shaft can be prevented.

Embodiments The features of the present invention will become more apparent from the following description of the embodiments shown in FIGS. 1a to 3c.

First, referring to FIGS. 1a to 1e, a sealing structure 10 according to the present invention is used to drive a shield machine 12 (see FIG. 1b) to form a circular cross section formed on a shaft wall 16 of a shaft 14. This is applied to the launch port 18 having a surface shape.

The shield machine 12 includes a shield body 22 to which a cutter head 20 is rotatably mounted in front. The shield machine 12 is mounted in the shaft 14 coaxially with the launch port 18 having a diameter larger than the outer diameter of the shield body 22, i.e., such that the axis of the shield body 22 is on the extension of the axis of the launch port 18. Can be

Behind the shield body 22, that is, behind the shield excavator in the propulsion direction (the right side in FIGS. 1b to 1e), a lining 24 (FIG. 1c) with a plurality of segments having smaller outer diameters is shielded. Subsequent to the body 22, it is arranged coaxially therewith. A tail seal 26 is provided on the inner rear end of the shield body 22 in order to achieve a seal between the shield body 22 and the lining 24.
Is attached.

The shield machine 12 is provided by extending a plurality of jacks (not shown) fixed to the inside of the shield main body 22 at intervals in the circumferential direction toward the front end of the lining 24. This is propelled as a reaction support. The lining 24 typically begins to form from inside the shaft and extends through the launch port 18.

Lining 24, other than the example of building this with the segment,
It may be formed from cast-in-place concrete or multiple pipes. When the lining is composed of the pipe, the pipe is disposed behind a shield machine and is propelled together with the shield body by actuation of a jack disposed in the shaft. The pipe propelled in this way also defines a conduit when it is of small diameter. Further, a pipe line may be laid by press-fitting only a pipe into the ground without using a shield machine and propelling the pipe. In this case, the pipe is arranged coaxially with the start port in the shaft, and by operation of a plurality of jacks (not shown) arranged in the shaft,
It is propelled underground through the launch port. Usually, the tip of the propulsion pipe to be propelled first is provided with a blade to facilitate propulsion.

In the present specification, the shield body 22, the lining 24, and the pipe are collectively referred to as a "hollow body", and the term "hollow body" is used as necessary. Among the shield main body 22, the lining 24, and the tube, one having a relatively large diameter is a tubular hollow body, and one having a relatively small diameter among the tubes is a tubular hollow body.

An elastic sealing material 30 such as a rubber plate constituting a part of the sealing structure 10 is disposed on the shaft wall 16 so as to face the starting port 18. The seal member 30 has a hole 31 that allows the hollow bodies of the shield body 22 and the lining 24 to penetrate. In the case of propulsion of only the pipe without using the shield machine, the sealing material is provided with a hole that allows a hollow body formed of the pipe to penetrate.

The illustrated seal material 30 has an annular shape as a whole, and the hole 31 has a lining 24.
Having a diameter smaller than the outer diameter of The axis of the hole 31 of the sealing material 30 is on an extension of the axis of the starting port 18. It is desirable that the shape of the hole 31 and the contour of the sealing material 30, that is, the shape of the outer edge be circular in accordance with the cross-sectional shape of the lining.

A plurality of metal fittings 32 are arranged behind the sealing material 30 at intervals around the hole 31. Each metal fitting 32 extending in the radial direction is fixed to the pit wall 16 by a fixing tool 36, together with the sealing member 30 and a pair of washers 34 partially sandwiching the outer peripheral edge 30a.

The metal fitting 32 is provided via an anchor bolt 36a constituting the fixing tool 36 and a first plate 32a fixed to the pit wall 16 by a nut 36b screwed thereto, and a spring steel plate 38 having a rectangular planar shape as a whole. A second plate 32b swingably attached to the first plate 32a and extending toward the hole 31 of the sealing material. In the illustrated example, the first and second plates 32b are arranged so that the second plate 32b can be swung.
A slight space is provided between a and 32b. When an axial force is applied to the second plate 32b, the second plate 32b rocks and the spring plate 38 bends elastically.
The opposite ends of the plates 32a, 32b may also be formed such that their front surfaces have a taper such that the thickness dimension gradually decreases toward the other side at their front surfaces, and butted against each other. The second plate can be swingable. The spring steel plate 38 and each plate
They can be joined together, such as by gluing, welding, welding, or using bolt and nut assemblies. Also,
The spring steel plate 38 can be fixed to the front surfaces of both plates instead of being fixed to the rear surfaces of both plates, or
It can be arranged between the two plates and fixed to both plates. Further, the spring steel plate 38 has another planar shape, and the number thereof can be two or more. Further, when the spring steel plate 38 is fixed to the front surfaces of both plates 32a and 32b, as shown in FIG. 1f, if both plates are set so as to abut each other or so that there is a slight gap between both plates, Due to the abutment of the second plate 32b against the first plate 32a, the rotational movement of the second plate 32b in the counterclockwise direction in the drawing is prevented. Therefore, in the case of this example, the arrangement of the later-described stopper 42 can be made unnecessary.

The anchor bolt 36a penetrating the outer peripheral edge 30a of the sealing material and the first plate 32a is attached to the pit wall 16 by embedding one end thereof in cocrete when the pit wall 16 is formed. When the pit wall is formed of a precast concrete plate, a socket is embedded in the precast concrete plate in advance, one end of a bolt is screwed into the socket, and a nut is screwed into the other end. When the downhole is made of steel, for example, a bolt is welded to the downhole and a nut is screwed. In any case, the fixture is
Other structures may be used as long as the seal member 30 and the metal fitting 32 can be fixed to the wellhead wall.

The metal fitting 32 holds the second plate 32 while the shield body 22 is being propelled.
The tip of b first contacts the outer peripheral surface of the shield body 22,
Next, it is positioned and arranged so as to contact the outer peripheral surface of the lining segment 24 following this. As will be described in detail later, when the shield machine 12 is propelled and passes through the start port 18, the second plate 32b receives the thrust thereof and also opposes the spring force of the spring steel plate 38. It is swung clockwise around the tangent of a circle centered on the extension of the 18 axis as seen in FIGS. 1b-1e. In order to facilitate the positioning of the metal fitting 32, the through hole 40 of the anchor bolt 36a provided in the first plate 32a is replaced with a second hole instead of a round hole.
It is desirable to use a long hole extending toward the plate.

Further, it is preferable that a stopper 42 extending from the second plate to the first plate 32a and attached to the rear surface of the first plate 32b be attached to the second plate 32b. By providing the stopper 42, the second plate
The second plate 32 when the abutting relationship between the shield body 32b and the shield body 12 or the lining segment 24 is released
The swing in the reverse direction of b (counterclockwise in FIGS. 1b to 1e) can be stopped. In the example shown, the stopper
The abutment of 42 against the rear surface of the first plate 32a keeps the second plate 32b such that the rear surface and the rear surface of the first plate 32a are in the same plane. The stopper 42 can be composed of, for example, a pair of plate members. The non-protruding portion of the plate, that is, the portion extending along the rear surface of the second plate 32b, also reinforces the second plate 32b.

1b to 1e showing a part of the seal structure near the top end
Referring to the figure, when the shield machine 12 is located behind the fitting 32 (FIG. 1b), the second plate 32b remains merely suspended in the vertical direction. When the shield machine 12 starts propulsion and the shield body 22 passes through the launching port 18 (FIG. 1c), the second plate 32b has its distal end in contact with the outer peripheral surface of the shield body 22. Under the thrust, it rotates angularly clockwise and maintains its rotational angle. At this time, a sealing material that allows penetration of the shield body 22
The peripheral edge of the hole 31 of 30, that is, the inner peripheral edge 30 b is bent forward to widen the hole 31, and the inner peripheral edge 30 b is
The start port 18 is sealed by the close contact with the outer peripheral surface 2. This sealing is performed by applying a second plate 3 to the rear surface of the seal member 30 which is subjected to the action of soil pressure caused by excavated earth and groundwater, more specifically, to the rear surface of the middle portion 30c between the inner and outer peripheral edges of the seal member.
Maintained by contact of 2b. As a result, the inner peripheral edge portion 30b of the sealing material is prevented from being bent to the opposite side, that is, the rear side. Thus, the sealing material 30 is supported by the second plate 32b.

The shield excavator 12 is further propelled to the second plate
When the tip of 32b comes into contact with the lining segment 24, the outer diameter of the lining segment 24 is smaller than the outer diameter of the shield body 22, so that the second plate 32b rotates slightly counterclockwise from the rotation angle position. And the angular position is maintained (1d
(Fig.), Similar to when the shield body 22 passes through the launch port 18,
The sealing material 30 is securely supported by the second plate 32b, and the sealing state of the starting port 18 is maintained well.

Further, as shown in FIG. 1e, when the propulsion direction of the shield machine 12 changes due to a sudden change in geology and the like, and the eccentricity occurs, the second plate 32b contacts the outer peripheral surface of the shield body 22 or the lining segment 24. In some cases, it becomes impossible to access and rotates counterclockwise. However, the stopper 42 abuts against the rear surface of the first plate 32a to prevent the second plate 32b from rotating further counterclockwise. As a result, the sealing member 30 is supported by the second plate 32b. Therefore, the inflow of excavated earth and sand, groundwater, and the like into the shaft 14 caused by the sealing material 30 under the action of the soil water pressure being bent in the opposite direction is prevented.

The cross-sectional shape of the starting port 18 is set to be similar to the cross-sectional shape of the tunnel or its lining.
The present invention is applied to a tunnel cross section having a cross section other than a circle, for example, a cross section having a so-called “eyeglass-shaped” cross section shown in FIG. 1g, a cross section having a rectangular cross section shown in FIG. 1h, and the like. It is possible.

The starting port 18 'to which the seal structure shown in FIG.
It has a cross-section of an outer shape excluding the overlapping portion of a pair of circles partially overlapping each other. The sealing material 30 'having elasticity is composed of a hole 31' having the same cross-sectional shape as that of the lining (not shown), that is, a part of a pair of circles, and two parallel straight lines or two curves connected to them. It has an outer shape hole edge. The illustrated sealing material 30 'has an outer edge shape similar to the cross-sectional shape of the launching port 18', and is arranged such that the distance between the outer edge and the launching port 18 'is equal.

In this example, a plurality of metal fittings 32 similar to those described above are
In addition, it is desirable to arrange a small metal fitting 33 outside the arrangement. Each metal fitting 33 is arranged corresponding to the two parallel straight lines of the hole 31 '.

In this seal structure, a shield machine having a twin-body shield body having two cutters is used to form a hole in a seal material 30 '.
Propelled through 31 '. At the time of propulsion, the hole 31 'of the sealing material 30'
Are successively brought into close contact with the shield body and the outer peripheral surface of the lining having the eyeglass-shaped cross-sectional shape following the shield body.

Further, in the example shown in FIG.
The hole 31 "of 0" and its outer edge form a rectangle similar to the cross-sectional shape of the start-up port 18 ".
The intersection of the 1 "diagonal is located on the axis of the launching port 18". In this example, four brackets 32 ″ are arranged along the four sides of the rectangle, and the first
The plate 32a "and the second plate 32b" each comprise an elongated plate member extending along each side of the rectangle.
The first and second plates in each metal fitting are joined via a plurality of spring steel plates 38 spaced from each other, and a plurality of stoppers 42 are attached to the second plate 32b ″.
Are mounted at intervals, and in the example shown, a spring steel plate
38 and stoppers 42 are alternately arranged. This example is particularly suitable for propulsion of a tube having a rectangular cross-sectional shape. Of course, it is also possible to use a shield machine having a shield body having a circular cross section larger than the hole 31 "of the sealing material 30". Also in this case, the periphery of the rectangular hole 31 ″ is in close contact with the shield main body having a circular cross-sectional shape penetrating the hole.

In addition, the seal structure according to the present invention, in addition to the illustrated example,
The present invention can also be applied to a launching port in which the cross section of the “glass type” extends in the vertical direction, and a launching port having another cross-sectional shape such as a polygon, an ellipse, and an oval.

The shield machine 12 started from the starting shaft 14 is propelled a predetermined distance to the reaching shaft.

Referring to FIGS. 2a to 2c, a sealing structure according to the present invention is provided between a reaching port 48 having a circular cross-sectional shape formed on a shaft wall 46 of a reaching shaft 44 and the hollow body penetrating therethrough. Sealed by 50.

The seal structure 50 is basically composed of the same components as those in the seal structure 10 of the starting port, that is, the seal member 30.
And a plurality of metal fittings 32 having first and second plates 32a and 32b and a spring steel plate 38 connecting these plates.
A pair of washers 34 for holding a part of the outer peripheral edge of the sealing material 30 and a fixing tool 36 for fixing the sealing material 30 and each metal fitting 32 to the pit wall 46 are used. With respect to the access port 48, it is arranged in the same manner as for the starting port of the component in the seal structure 10. Therefore,
The arrangement of these components is symmetrical to the arrangement of the components 30, 32a, 32b, 34, 36, 38 in the seal structure 10 of the launch port 18. That is, one of the washers 34, the sealing material 30 coaxial with the arrival port 48, the other of the washers 34, and the metal fitting 32 are sequentially overlapped from the rear in the propulsion direction to the front.

According to this seal structure 50, as shown in FIG. 2c, when the shield body 22 of the propelled shield machine 12 passes through the arrival port 48 and passes through the seal material 31, it is the peripheral edge of the hole 31. The inner peripheral edge 30b is bent forward in the propulsion direction.
The bent inner peripheral edge portion 30b is in close contact with the shield main body 22, and the space therebetween is sealed.

However, at the arrival port 48, unlike at the starting port, the direction of action of the soil water pressure on the sealing material 30 is the bending side of the inner peripheral edge 30b of the sealing material, that is, the front side in the propulsion direction, so that the hole 31 of the sealing material Is easy to spread. For this reason, the sealed state is unstable.

According to the present invention, while the inner peripheral edge portion 30b of the sealing material is bent, the intermediate portion 30c contacts the second plate 32b,
The plate is swung against the spring force of the spring steel plate.
Therefore, in the appropriate swing position of the second plate 32b, the intermediate portion 30c receives a spring biasing force rearward in the propulsion direction from the spring member 38 having the spring energy stored by bending through the second plate 32b. For this reason, the expansion of the hole 31 of the sealing material is suppressed, and thereby a stable sealed state is obtained.

In addition, it is desirable to attach a stopper 52 that can abut the front surface of the first plate 32a to the second plate 32b. The stopper 52 is composed of a pair of plate members parallel to each other.
Each of the illustrated plate members has a parallelogram shape as a whole, and is fixed to the front surface of the second plate 32b at one of the opposite sides of the parallelogram. Each plate member swings together with the second plate, and abuts the first plate 32a on the other side adjacent to the one side of the parallelogram. Since the overall shape of each plate member is a parallelogram, when the stopper 52 comes into contact with the first plate 32a, the second plate 32b forms an angle with the first plate 32a. Thereby, the bending of the inner peripheral edge 30b of the sealing material is guaranteed, and the deformation of the inner peripheral edge 30b and the intermediate portion 30c due to unexpected sudden high soil water pressure is limited. Groundwater is prevented from flowing into the shaft 44. In order to obtain such an effect, the planar shape of each stopper is set to an obtuse triangle, each stopper is fixed to the second plate at one of two sides forming an obtuse angle of the triangle, and the other side is The first plate may be abuttable.

Also, instead of providing the stopper 52 or together with the stopper, a cable 54 such as a wire can be provided. The ropes 54 are sequentially passed through U-shaped members 56 having both ends fixed to the center of the front surface of each second plate 32b. Both ends 54a, 54b of the cable extending crossing each other when passing through the U-shaped member 56 of the metal fitting located at the top end are fixed to the pit wall 46 so that the cable 54 is placed in tension. As a result, the rope 54 extends along a circle having a center on the extension of the axis of the arrival port 48, and sequentially connects the second plates 32b so as to be relatively movable. As shown in FIG. 2a, it is desirable that both ends of the cable 54 are substantially at the same level as the U-shaped member 56 of the second plate 32b located at the top end. Instead of the U-shaped member 56, a perforated plate member or a hook-shaped member opened to the side of the first plate 32a of the metal fitting can be used.

It is desirable that one of the two ends of the cable 54, for example, one end 54a, be fixed to the wellbore via a tensioning device 58.
The illustrated tensioning device includes a frame, and a drum (not shown) rotatably supported by the frame and whose rotation direction is regulated by a ratchet mechanism. A hook that moves toward the frame is connected to the drum, and an operation lever for applying a rotational force to the drum in one direction is attached. One end 54a of the cord is connected to the hook, and the tensioning device 58 is connected to another hook fixed to the frame on the opposite side of the hook by a driving pin or an embedding pin (not shown) into the pit wall 46. Are linked. Also, the other end 54 of the cable
b is connected to a driving pin or a buried pin (not shown) into the pit wall 46. According to this tensioning device, the rope can be easily tensioned and maintained in this state by rotating the drum in one direction with the operation lever. Instead of the illustrated example, at least one of the two ends of the rope can be fixed to a support such as a belly or a cutout installed to maintain the shaft.

When the second plate 32b swings, the U-shaped member 56 moves outward in the radial direction. Along with this
54 stretches elastically. For this reason, the intermediate portion 30c of the seal member receives a biasing force toward the rear in the propulsion direction via the second plate 32b, whereby the expansion of the intermediate portion 30c and the inner peripheral edge associated therewith are caused. Peeling of the 30b from the shield body 22 is limited.

By the way, the shield excavator or the lining propelled from the launch port 18 having a circular cross-sectional shape, as is apparent from the above description, reaches the pit via the arrival port 48 having the same circular cross-sectional shape as the launch port. Accepted to. Similarly, a shield excavator propelled through a launch port having a “glass-shaped” cross-sectional shape as shown in FIG. 1g is received in an arrival shaft having an access port having the same shape as the launch port. Similarly, a pipe or shield machine propelled through a launch port having a rectangular cross-section as shown in FIG. 1h is also received in a shaft having the same rectangular destination as said launch port.

As shown in FIG. 2d, a sealing material 30 ′ having a hole 31 ′ is symmetrically provided at the arrival port 48 ′ of the “eyeglass type”, similarly to the start port 18 ′, as in FIGS. 2a to 2c. Metal fittings 32 and 33 each having a stopper 52 are arranged, and a cable 54 connecting the metal fittings is arranged. The cord 54 extends through the U-shaped members 56 of each second plate along the outline of the "eyeglass-shaped" shape, with both ends passing through the U-shaped members 56 of the five second plates near the top end. Overlap in between.

As shown in FIG. 2e, a seal member 30 "having a hole 31", a stopper 52, and a cable 54 are arranged in the rectangular arrival port 48 "symmetrically with the start port 18". Rope
54 extend along the four sides of the rectangle through a plurality of U-shaped members 56 provided on each second plate 32b ", and a plurality of U-shaped members 56 of the second plate whose both ends are located at the top end. At partially overlap.

In each of these examples, the rope 54 and the stopper 52 limit the swing of the second plate accompanying the bending of the inner peripheral edge of the hole of the seal material through which the shield body or the lining penetrates, respectively. Stop it.

3a to 3c another sealing structure 60 for the access port 48
Is shown. This seal structure 60 is the second
This differs from the seal structure 50 shown in FIGS. 2A to 2C.

The metal fitting 62 having the sealing structure has a third plate 32c in addition to the first and second plates 32a and 32b.
The third plate 32c includes the first and second plates 32a, 32
It is attached to the second plate 32b via a spring steel plate 64 similar to the spring steel plate 38 connecting the 2b, and can abut on the inner peripheral edge 30b of the sealing material. The second and third plates are interconnected similarly to the first and second plates.

According to the seal structure 60, the shield main body 22 passes through the circular hole of the seal material 30, whereby the inner peripheral edge portion 30b
Is bent, the inner peripheral edge of the third plate 32
Touch c. Accordingly, the third plate 32c moves forward together with the inner peripheral edge portion 30a while swinging with respect to the second plate under the thrust, and during this time, the second plate 32b
Swings with respect to the first plate 32a. The bent inner peripheral portion 30b is connected to the third plate 32c via the third plate 32c.
Spring steel plate 64 bent as the plate oscillates
Is pressed against the shield body 22 under the spring bias force of
Good adhesion is realized.

Further, the seal structure 60 has, in addition to the cable 54 connecting the second plate 32b, a cable 66 such as a wire connecting the third plate 32c,
The structure differs from the seal structure 50 in that a stopper 68 provided on the front surface of the second plate 32b is provided on the front surface of the second plate 32b.

On the front surface of each third plate 32c, the same U
The character member 70 is fixed, the cable 66 is passed through the member 70,
As seen in FIG. 3a, the inside of the cord 54 extends concentrically with it. Rope 66
As in the case of the cable 54, the both ends extend crossing each other when passing through the U-shaped member 70 of the metal fitting at the top end, and are fixed to the pit wall 44. One end of the cord 66 is connected to a tensioning device 72 similar to the tensioning device 58 applied to the cord 54 for tensioning. At least one end of the cable 66 can also be fixed to the support.

The rope 66 elastically extended with the swing of the third plate 32c exerts a pressing force on the inner peripheral edge portion 30b of the sealing material toward the shield main body 22. Also, the spring steel plate 38 and the elastically elongated rope 54 bent along with the swinging of the third plate 32c exert a rearward force on the second plate 32b. The forward bulging due to the action of the soil pressure of 30c is suppressed.

The stopper 68 is composed of a pair of plate members exhibiting an obtuse triangle as a whole, and each plate member is fixed to the front surface of the third plate 32c at one of the adjacent sides that define the obtuse angle of the obtuse triangle, and the other of the adjacent sides. At the second plate 32b
Can be abutted against a stopper 52 fixed to the front surface of the second plate 32b, more precisely. The stopper 68 has a function of reliably stopping the swing of the third plate 32c with respect to the second plate 32b.

FIGS. 4a-1 to 4c-2 show other seal structures for the access port 48, which are not the seal structure according to the present invention, but for comparison. The seal structure 71 shown in FIGS. 4a-1 to 4c-1 is such that the first and second plates forming a part of the metal fitting 73 are pivotally attached to each other via a pivot, that is, a pin. 2a to 2c in that
The structure is different from that of the seal structure 50 shown in FIG. 2c. Further, in the seal structure 50, the plates are connected to each other by an elastically deformable plate member, and when each plate relatively swings, it acts to limit this, so that the relative swing of the plates is suppressed. An additional stop 52 or restraining cord 54 is required. On the other hand, in this seal structure 71, since the second plate can swing indefinitely,
At least one of a stopper for suppressing the swing and a cable for suppressing the swing is required, and in this regard, the structure of the seal structure 71 is different from that of the seal structure 50.

The first and second plates 73a and 73b of the metal fitting 73 in the seal structure 71 are connected to each other and have a tubular end through which a pin 78 is inserted as shown in FIGS. 4a-1 and 4b-1. Have each.

Attached to the second plate 73b, the first plate 7
The stopper that can contact the front surface of 3a is the same as the stopper in the seal structure 50. To avoid repetition of description, the same reference numeral 52 as in the seal structure 50 is used only. A part of each stopper 52 is provided on the second plate 73.
An engageable recess (not shown) is provided in the tubular end of b and the recess is fixed to the tubular end.

Further, since the rope is also the same as in the seal structure 50, the same reference numeral 54 is attached and the description is omitted. One end of the cable 54 passing through the U-shaped member 56 provided on the second plate 73b is preferably fixed to the pit wall 46 via a tensioning device 58 similar to the above-described tensioning device.

According to this seal structure 71, when the shield main body 22 passes through the hole 31 of the seal material 30, the inner peripheral edge 30b of the seal material is bent forward, and the second plate 73b is
As seen in FIG. 1, it is swung clockwise. The cable 54 is elastically extended and restrains the clockwise swing of the second plate 73b, and the stopper 52 is locked to the first plate 73a, and the locked second plate 73b is locked to the first plate 73a. Stop rocking.

A fitting formed by further pivotally connecting a third plate to the second plate can be used. 4a-2 to 4c-
FIG. 2 shows another seal structure 74 in which the metal fitting 76 is used. The first and second plates 76a and 76b and the second and third plates 76b and 76c are swingably connected via pins 78, respectively.

In the seal structure 74, in order to limit and stop the swing of the third plate 76c with respect to the second plate 76b, a cable 66 is provided around the U-shaped member 70 attached to the third plate 76c to connect them. In addition, a pair of stoppers 68 is attached to each third plate 76c so as to be able to abut the front surface of the second plate 76b (more precisely, a stopper attached to this). It is desirable that both the cord and the stopper are provided, but at least one of them may be provided.

4a-2 and 4b-2, the second and third plates 76b, 76c each have a tubular end engaged with each other and having a pin 78 inserted therethrough, and each stopper 68, a part of which is the second and third plates 76b and 76c.
An engageable recess (not shown) is provided in the tubular end of and is secured to the tubular end. Also,
Preferably, one end of the cable 66 is fixed to the pit wall 46 via a tensioning device 72 similar to the tensioning device described above.

According to the sealing structure 74, when the shield body 22 passes through the hole 31 of the sealing material 30, the inner peripheral edge 30b of the sealing material is bent forward, and the second and third plates 76b,
76c are respectively swung clockwise in FIG. 4c-2. The cords 54, 66 extend elastically and inhibit the clockwise swinging of the second and third plates 76b, 76c, respectively, and the stoppers 52, 68 provide the first and second plates 7
6a and 76b, respectively, and stops the swing of the second and third plates 76b and 76c after the locking.

In this way, the close contact between the hollow body and the sealing material is maintained by the contact between the hollow body such as the shield machine, the lining, and the pipe and the sealing material and the fitting.

The arrival port to which the present invention is applied is not limited to the above example, and may have another cross-sectional shape as described for the start port.

In addition, one or a plurality of recesses for passing a backing material injection tube that moves together with the shield body may be provided at an edge of the start port or the arrival port. It goes without saying that the application of the present invention includes a start port or an arrival port having such a concave portion.

[Brief description of the drawings]

Fig. 1a is a front view of the seal structure of the starting port, Figs. 1b, 1c and 1d are longitudinal sectional views near the top end of the seal structure which change with the propulsion of the shield machine, and Fig. 1e is the shield machine. FIG. 1f shows another example of the bracket when the machine is eccentric, FIG. 1f shows another example of the bracket, FIG. 1b is a sectional view similar to FIG. 1g, and FIG. 1g and FIG. Front view, 2a, 2b of a seal structure applied to a launch port having a shape
Figures 2c and 2c are front views of the seal structure at the arrival port and longitudinal sectional views near the top end of the seal structure changing with the propulsion of the shield machine, and Figures 2d and 2e are Figures 1g and
1h is a front view of the seal structure of the arrival port having a cross-sectional shape corresponding to the cross-sectional shape of the launch port shown in FIG. 1h, FIG. 3a, FIG. 3b, and FIG. FIG. 4a-1, FIG. 4b-1 and FIG. 4c-a vertical cross-sectional views of the vicinity of the top end of the seal structure which change with the propulsion of the shield machine.
FIG. 1 is a front view of another seal structure not depending on the present invention at the arrival port and a longitudinal sectional view near the top end of the seal structure which changes according to the propulsion of the shield machine, FIGS. 4a-2, 4b-2 and Fig. 4c-2 is a front view of another seal structure not depending on the present invention at the arrival port, and a vertical cross-sectional view near the top end of the seal structure which changes according to the propulsion of the shield machine, Figs.
Fig. 5b is a front view of a conventional seal structure of a starting port and a longitudinal sectional view near the top end thereof, and Fig. 6 is a front view of a conventional seal structure of a reaching port. 10: Seal structure of launching port, 12: Shield excavator, 14, 16, 18: Launching pit, its pit wall and launching port, 22: Shield body, 24: Lining, 30, 30 ', 30 "and 31, 31 ', 31 ": sealing material and its hole, 32, 33, 32": metal fittings, 32a, 32b, 32c: first, second and third plates, 32a ", 32b", 32c ": first, Second and third plates, 36: fixture, 38,64: spring steel plate, 42: stopper, 44,46,48: reaching shaft, its pit wall and reaching port, 50,60,71,74: reaching port Seal structure of 52,68: stopper, 54,66: cable.

Claims (11)

(57) [Claims] 1. A seal structure for a launch port formed on a pit wall of a launch shaft, comprising a hole that is disposed opposite to the launch port and that allows a tubular or tubular hollow body to penetrate therethrough. An elastic sealing material having a peripheral edge defining a hole that can be in close contact with the hollow body; and a plurality of metal fittings disposed behind the sealing material in the propulsion direction and spaced from each other around the hole in the sealing material. And a fixture for fixing the sealing material and the fitting to the pit wall, wherein each fitting is fixed to the pit wall by the fixing tool, and a first plate facing the sealing material; and The first through an opposing spring steel plate;
A second plate attached to the plate and extending toward the side of the hole of the seal material and facing the seal material, wherein the second plate is capable of contacting the outer peripheral surface of the hollow body at a tip end thereof. The starting port seal structure. 2. The starting port sealing structure according to claim 1, further comprising a stopper fixed to said second plate and capable of abutting on a rear surface of said first plate. 3. The seal structure according to claim 1, wherein said first and second plates abut against each other, and said spring steel plate is fixed to a front surface of both plates. 4. A seal structure for an access port formed in a pit wall of an access shaft, comprising a hole that is disposed opposite to the access port and that allows a cylindrical or tubular hollow body to pass therethrough. An elastic sealing material having a peripheral portion defining a hole that can be in close contact with the hollow body; and a plurality of metal fittings disposed in front of the sealing material with respect to the propulsion direction and spaced from each other around the hole of the sealing material. And a fixture for fixing the sealing material and the fitting to the pit wall, wherein each fitting is fixed to the pit wall by the fixing tool, and a first plate facing the sealing material; and The first through an opposing spring steel plate;
And a second plate attached to the plate and extending toward the side of the hole of the seal material and facing the seal material. 5. The arrival port sealing structure according to claim 4, further comprising a stopper attached to said second plate and capable of abutting on a front surface of said first plate. 6. A cable for sequentially connecting said second plate so as to be relatively movable with respect to said plate, and both ends of which are fixed to said downhole wall or a support for said downhole wall. The reaching port sealing structure according to claim 4, further comprising a cable. 7. The apparatus according to claim 7, wherein said second stopper and said second stopper are provided.
A cable that sequentially connects the plates in a manner that allows relative movement with respect to the plate, the ropes being fixed at both ends to the downhole or a support for the downhole. ). 8. A seal structure for an access port formed in a shaft of an access shaft, comprising a hole disposed to face the access port and allowing a cylindrical or tubular hollow body to penetrate therethrough. An elastic sealing member having a peripheral edge defining a hole that can be in close contact with the hollow body; a plurality of metal fittings disposed in front of the sealing material and spaced from each other around the hole of the sealing material; A sealing member and a fixture for fixing the fitting to the pit wall, wherein each fitting is fixed to the pit wall by the fixing tool, a first plate facing the sealing material, and a spring facing the sealing material. A second plate attached to the first plate via a steel plate and extending toward the side of the hole of the seal material and facing the seal material; and a second plate via a spring steel plate facing the seal material. Of the sealing material attached to the plate And a third plate to the periphery possible contact of the seal structure of the access openings. 9. A stopper attached to the second plate and capable of contacting the front surface of the first plate, and a stopper attached to the third plate and attached to the front surface of the second plate. The arrival port sealing structure according to claim 8, further comprising a contactable stopper. 10. A cable for sequentially connecting said second plate so as to be relatively movable with respect to said plate, wherein both ends thereof are fixed to said downhole wall or a support for said downhole wall. A cable for sequentially connecting the third plate to the third plate so as to be relatively movable with respect to the plate, and both ends of which are fixed to the downhole wall or a support for the downhole wall; The sealing structure of an arrival port according to claim (8), comprising: 11. A stopper attached to the second plate and capable of abutting on the front surface of the first plate, and a stopper attached to the third plate.
A stopper which can be brought into contact with the front surface of the plate, and a cable which sequentially connects the second plate so as to be able to move relative to the plate, and both ends of which are supported by the downhole or the downhole. A cable fixed to a work, and a cable for sequentially connecting the third plate so as to be able to move relative to the plate, and both ends of which are fixed to the downhole wall or a support for the downhole wall. Claim (8), comprising:
The seal structure of the arrival port described in 1.