JP2006063654A - Packing for sealing shield pit mouth, and shield pit mouth sealing structure using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide packing and a structure for sealing a shield pit mouth, which can maintain a sealing function even if the pressure of groundwater and sediment in a tunnel boring section is high. <P>SOLUTION: This packing comprises: a strip-shaped rubber member which has a predetermined width and a length almost equal to the length of an inner periphery of a tubular member 50, which is arranged along an inner peripheral surface of the tubular member 50, and which is expanded to the central side of the tubular member 50 by pressure water or pressure air, supplied from the side of the tubular member 50; a fiber-reinforced layer 54 which is embedded throughout a rubber member 52; mounting parts 53 and 53 which are provided at both the side ends of the rubber member 52, which are thicker than the rubber member 52, which are locked to a fixing member 58 provided in the tubular member 50, which are held in the state of being sandwiched between the fixing member 58 and the tubular member 50, and which are held in prescribed positions; and an anti-coming-off member 11 which has predetermined rigidity and strength, which is thicker than the rubber member 52, and which is embedded in the mounting part 53. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a shield well seal sealing and a shield well seal structure using the same, and particularly to a shield well seal packing suitable for excavating a tunnel to the side of a vertical shaft and the like. The present invention relates to a shield wellhead sealing structure.

  When excavating a tunnel with a shield machine to the side of a shaft, to prevent groundwater and earth and sand contained in the tunnel excavation part from flowing into the shaft from the gap between the outer surface of the shield machine and the inner surface of the tunnel Various sealing structures have been proposed (see, for example, Patent Documents 1 to 4).

  As shown in FIG. 8, the sealing structure described in Patent Document 1 is provided at the entrance or exit of the tunnel 62 (FIG. 8 shows the entrance), and has a cylinder having an inner diameter larger than the outer diameter of the shield machine 61. A cylindrical member 50 and a packing 51 disposed along the inner peripheral surface of the cylindrical member 50. Note that the gap between the tubular member 50 and the tunnel 62 is filled with concrete or the like in order to prevent leakage of groundwater and earth and sand in the tunnel excavation portion from here.

  As shown in FIG. 9, the packing 51 includes a belt-like rubber member 52 and attachment portions 53 having wedge-shaped cross sections provided at both end portions thereof.

  A fiber reinforcing layer 54 is embedded in the rubber member 52 and the attachment portion 53 as shown in FIG. The fiber reinforcing layer 54 is formed by laminating two layers of fiber members 55 and 55.

  In addition, the fiber reinforcing layer 54 is embedded in the attachment portion 53 with a predetermined interval between the two fiber members 55 and 55 in the vicinity of the base portion of the attachment portion 53.

  Further, in the attachment portion 53, other reinforcing fibers 56 and 56 are embedded in the fiber members 55 and 55. A hard rubber 57 is provided between the fiber members 55 and 55 in the attachment portion 53.

  As shown in FIG. 8, of the attachment portions 53, 53 of the packing 51, one attachment portion 53 arranged on the shaft 60 side has one surface 53 a on the inner peripheral surface 50 a of the tubular member 50. In the abutted state, it is locked by a fixing member 58 provided on the inner peripheral surface of the cylindrical member 50 and is held between the fixing member 58 and the cylindrical member 50 and held at a predetermined position. .

  Further, the other attachment portion 53 fixed to the tunnel 62 side is folded back so as to enter between the rubber member 52 and the tubular member 50, and the other surface 53 b of the attachment portion 53 is made the inner periphery of the tubular member 50. While being in contact with the surface 50a, it is locked to the fixing member 58, and is held between the fixing member 58 and the tubular member 50 and held at a predetermined position.

  Further, pressurized air or pressurized water is supplied from a supply port 59 provided in the tubular member 50 into a closed space 65 formed between the rubber member 52 and the tubular member 50, so that the rubber member 52 is completely removed. It expands in the shape of a tire toward the center of the cylindrical member 50 over the circumference. The diameter of the inner peripheral surface of the rubber member 52 after expansion is smaller than the diameter of the outer peripheral surface 61 a of the shield machine 61.

As a result, the inner peripheral surface 52a of the rubber member 52 expanded in a tire shape becomes the shield machine 61.
The gap between the cylindrical member 50 and the shield machine 61 is sealed.

  Therefore, at the entrance of the tunnel 62, the groundwater and earth and sand contained in the tunnel excavation part can be prevented from flowing into the shaft 60 through the gap between the inner peripheral surface of the tunnel 62 and the outer peripheral surface 61a of the shield machine 61.

  Patent Document 2 describes a packing that increases the clamping force of the mounting portion 53 by the fixing member 58 and the cylindrical member 50 by providing protrusions on the mounting portions 53 and 53. A packing is described in which a closed space 65 formed between the rubber member 52 and the tubular member 50 is filled with an elastic member that is bridged inside the space instead of pressurized water or pressurized air. Has been.

Further, in Patent Document 4, in order to prevent the mounting portion 53 from moving from a predetermined position when the pressure water or the pressure air in the closed space 65 is increased, the fixing member 58 includes A packing in which irregularities are provided on the contact surface with the mounting portion 53 is described.
JP-A-8-35392 Japanese Patent Laid-Open No. 8-277693 JP-A-8-312287 JP 2001-12183 A

  However, when the tunnel excavation position is deep and the pressure of groundwater and earth and sand contained in the tunnel excavation part is as high as about 1.0 MPa, the water pressure supplied into the packing 51 is used to seal the groundwater and earth and sand pressure. Alternatively, it is necessary to increase the air pressure. However, when the hydraulic pressure or air pressure supplied to the inside of the conventional packing 51 is increased, a large tension is generated in the rubber member 52, and the attachment portion 53 is detached from the fixing member 58 by this tension. There was a risk of it.

  As described above, when the packing 51 is detached from the fixing member 58, the sealing function of the packing 51 is lost, and the groundwater and earth and sand in the tunnel excavation part are removed from the inner peripheral surface 50a of the cylindrical member 50 and the outer peripheral surface of the shield machine 61. The problem of flowing out into the shaft 60 arises from the gap.

  The present invention has been made in view of such problems. Even when the pressure of groundwater and earth and sand contained in the tunnel excavation portion is high, the sealing function of the packing can be maintained, and the groundwater and earth and sand flow out into the vertical hole. It is an object of the present invention to provide a shield well-sealing packing capable of reliably preventing this and a shield hole-sealing structure using the same.

The present invention employs the following means in order to solve the above problems. That is, in the present invention, when excavating a tunnel by a shield machine to the side of the shaft, the ground water contained in the ground to be excavated from the tunnel from the gap between the outer peripheral surface of the shield machine and the inner peripheral surface of the tunnel, In order to prevent earth and sand from flowing into the shaft, it is disposed along the inner peripheral surface of a cylindrical member provided at the entrance or exit of the tunnel and having an inner diameter larger than the outer diameter of the shield machine, A packing that is in close contact with the outer peripheral surface of the shield machine,
It has substantially the same length and a predetermined width as the inner peripheral length of the cylindrical member, is arranged along the inner peripheral surface of the cylindrical member, and is supplied by pressure water or pressure air supplied from the cylindrical member side. A band-shaped rubber member that expands toward the center of the cylindrical member;
A fiber reinforcement layer embedded over the entire surface of the rubber member;
The rubber member is provided at both end portions of the rubber member, has a thickness larger than that of the rubber member, is locked to a fixing member provided in the cylindrical member, and the fixing member and the cylindrical shape An attachment portion sandwiched between members and held in a predetermined position;
And a retaining member embedded in the mounting portion and having a predetermined rigidity and strength and a thickness greater than that of the belt-shaped rubber member.

  The two-layer fiber member in the fiber reinforcement layer can be formed, for example, by weaving polyester reinforcement cords in one direction. In this case, the two-layer reinforcing member is preferably arranged so that the polyester reinforcing cords cross each other.

  In the present invention, since the retaining member having a predetermined strength and a thickness larger than the thickness of the rubber member is embedded in the mounting portion, a high pressure is applied in the closed space formed between the rubber member and the cylindrical member. Even when water or pressurized air is supplied and a large tensile force acts on the mounting portion from the rubber member, the retaining member does not come off the fixing member, so that the mounting portion is held at a predetermined position. Thereby, the sealing function of packing can be maintained.

  Here, it is preferable that the retaining member is a linear member made of steel or resin. In this case, the retaining member can be easily obtained, and the retaining member can be easily embedded in the mounting portion by insert molding.

  Further, the fiber reinforcing layer is formed by two-layer fiber members laminated, and the two-layer fiber members are separated inside the mounting portion and arranged at a predetermined interval from each other. It is preferable that different reinforcing fibers are laminated on the two-layer fiber member.

  In this case, since the strength of the attachment portion is increased, it is possible to prevent the attachment portion from being damaged even when the pressure water or pressure air supplied into the closed space is high.

Further, the present invention is a shield wellhead sealing structure using the shield well seal sealing described above,
A cylindrical member provided at the entrance or exit of the tunnel and having an inner diameter larger than the outer diameter of the shield machine;
A fixing member that is fixed at a predetermined position of the tubular member, the attachment portion in the shield wellhead packing is locked, and a fixing member that sandwiches the attachment portion in cooperation with the tubular member;
Provided in the cylindrical member to supply pressurized water or pressurized air having a predetermined pressure into a closed space formed between the inner peripheral surface of the cylindrical member and the rubber member in the packing. A supply port,
Of the mounting portions in the packing, one of the mounting portions is fixed with one surface abutting against the inner peripheral surface of the tubular member, and the other mounting portion is folded back to the other surface. Is fixed in contact with the inner peripheral surface of the cylindrical member.

  The cylindrical member is preferably a cylindrical member, but various cylindrical members such as a polygon can be used.

  In the present invention, even when the pressure of ground water and earth and sand in the tunnel excavation part is high, it is possible to prevent the packing from being detached from the fixing member and losing the sealing function, so that the shield wellhead can be reliably sealed.

  As described above, according to the present invention, the sealing function of the packing is maintained when the pressure of pressurized water or pressurized air supplied into the packing is increased according to the pressure of groundwater and earth and sand in the tunnel excavation part. Since it can do, it can prevent reliably that the groundwater and earth and sand in a tunnel excavation part flow into a shaft.

  Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. In addition, the same code | symbol is attached | subjected to the part similar to FIGS. 8-10, and the detailed description is abbreviate | omitted.

(First embodiment)
FIG. 1 shows a shield 1 for sealing a shield wellhead according to a first embodiment of the present invention. The shield well sealing gasket 1 includes a belt-like rubber member 52 and attachment portions 53 and 53 provided on both side ends of the rubber member 52 and having a wedge-shaped cross section. Inside the attachment portions 53, 53, a linear retaining member 11 is embedded over the entire length.

  The belt-shaped rubber member 52 has a length L substantially the same as the inner peripheral length of the cylindrical member 50 provided at the entrance of the tunnel 62 (see FIG. 3) and a predetermined width W. Further, as shown in FIG. 2, a fiber reinforcing layer 54 is provided over the entire surface of the rubber member 52 inside the rubber member 52.

  The fiber reinforcing layer 54 is formed by laminating two layers of fiber members 55 and 55. Each of the fiber members 55, 55 is woven with, for example, polyester reinforcing cords arranged in one direction. The laminated two-layer fiber members 55, 55 are arranged so that the mutual polyester reinforcing cords cross each other.

  The two-layer fiber members 55 and 55 are stacked in the rubber member 52, but are separated in the vicinity of the root portions of the attachment portions 53 and 53. These separated two-layer fiber members 55 and 55 are arranged on the front and back surfaces 53a and 53b side of the attachment portions 53 and 53, respectively, with a predetermined interval therebetween.

  Further, the thicknesses t1 of the attachment portions 53, 53 are formed to be thicker than the thickness t2 of the rubber member 52. In these attachment portions 53, 53, another reinforcing fiber 56, 56 is laminated and embedded in two layers of fiber members 55, 55.

  Further, a hard rubber 57 is provided between the two-layer fiber members 55 and 55 in the attachment portions 53 and 53.

  The retaining member 11 is embedded in the hard rubber 57 in the vicinity of the root portions of the attachment portions 53 and 53. The thickness (diameter) D of the retaining member 11 is formed to be considerably larger than the thickness t1 of the rubber member 52. In this example, the diameter of the retaining member is formed to be about three times the thickness t1 of the rubber member 52.

  As the retaining member 11, a linear member made of steel or resin having predetermined rigidity and strength can be used. In this example, a steel strand wire is used as the retaining member 11. In addition, the rigidity and strength of the retaining member 11 are higher than those of the surrounding members, in this example, that of the hard rubber 57.

  As is well known, a core net is arranged in the center of this strand wire, and since the strands are formed by a plurality of layers around the core wire, the mounting portions 53 and 53 incorporating this are provided. It can be easily deformed along the inner peripheral surface of the cylindrical member 51 (see FIG. 6).

As described above, the packing 1 of the present invention has a predetermined rigidity and strength in the mounting portions 53 and 53 having a thickness t2 larger than the thickness t1 of the rubber member 52 and is larger than the thickness t1 of the rubber member 52. Since the retaining member 11 having a large thickness (diameter) D is embedded, as described later, in a closed space 65 (see FIG. 5) formed between the rubber member 52 and the cylindrical member 51, It is possible to prevent the attachment portions 53 and 53 from being detached from the fixing member 58 when high-pressure water or pressure air is supplied.

  In addition, since the retaining member 11 is a steel strand wire, a commercially available product can be easily obtained, and the retaining member 11 can be easily embedded in the mounting portions 53 and 53 by insert molding. Further, the rubber member 52 incorporating the auxiliary stopper 11 can be easily deformed along the inner peripheral surface of the cylindrical member 50.

  In addition, since the retaining member 11 is in contact with both the fiber members 55 and 55 in the attachment portions 53 and 53, a force that pulls the attachment portions 53 and 53 in the center line direction of the cylindrical member 50 acts. Also, it is possible to prevent the mounting portions 53 and 53 from being crushed. Thereby, it can prevent that the attaching parts 53 and 53 remove | deviate from the fixing member 58. FIG.

  In this example, a hard rubber 57 is provided in the attachment portions 53, 53, and this hard rubber 57 functions as a retaining member when the pressure of groundwater and earth and sand contained in the tunnel excavation portion is relatively low. To do.

  However, if the above-described retaining member 11 is not provided, the hard rubber 57 is deformed and the function as a retaining member is lowered when the pressure of groundwater and earth and sand contained in the tunnel excavation portion is high.

  Therefore, in the present invention, the retaining member 11 having higher rigidity and strength than the hard rubber 57 is provided in the hard rubber 57, so that the retaining member can be used even when the pressure of groundwater and earth and sand contained in the tunnel excavation portion is high. 11 is prevented from being deformed, and the function as a retaining member can be reliably maintained.

  In addition, since the reinforcing members 56 and 56 are laminated on the fiber members 55 and 55 that are spaced apart from each other in the attachment portions 53 and 53, respectively, When a tensile force in a direction crossing the thickness direction is applied, it is possible to prevent the attachment portions 53 and 53 from being extended or damaged.

  In the above-described embodiment, the case where the fiber members 55 and 55 and the reinforcing fibers 56 and 56 are arranged on the front and back surfaces 53a and 53b side of the attachment portions 53 and 53 and the retaining member 11 is embedded therebetween is described. However, as shown in FIG. 3, the retaining member 11 may be embedded without providing the reinforcing fibers 56, 56 in the attachment portion 53.

  Further, as shown in FIG. 4, the mounting portions 53 and 53 can be provided with one or more rows of protrusions 75 protruding from the front and back surfaces 53a and 53b. FIG. 4 shows a case where the protrusions 75 are provided in a row.

  Thus, by providing the protrusions 75 on the attachment portions 53, 53, the clamping force between the fixing members 58, 55 and the tubular member 51 with respect to the attachment portions 53, 53 is increased, so that the attachment portions 53, 53 are fixed. Detachment from the member 58 can be prevented.

(Second Embodiment)
FIG. 5 shows a shield wellhead sealing structure using the shield wellhead packing according to the second embodiment of the present invention.

This shield wellhead sealing structure is provided at the entrance or exit of the tunnel 62, in this example, at the entrance of the tunnel 62, when the tunnel 62 is excavated to the side of the shaft 60 by the shield machine 61. A cylindrical member 50 as a cylindrical member having a large inner diameter, the packing 1 provided on the inner peripheral surface of the cylindrical member 50, and the attachment portions 53 and 53 on both side ends of the packing 1 are spaced apart from each other by a predetermined distance. The wedge-shaped root portions of the mounting portions 53 and 53 are locked so as to be fixed to the inner peripheral surface of the cylindrical member 50 and the mounting portions 53 and 53 cooperate with the inner peripheral surface of the cylindrical member 50. And fixing members 58, 58 that hold the pin.

  The cylindrical member 50 has a predetermined space in a closed space 65 formed between the rubber member 52 and the cylindrical member 50 in order to expand the band-shaped rubber member 52 in the packing 1 toward the center of the cylindrical member 50. A supply port 59 for supplying pressure air or pressure water having pressure, in this example, pressure water is provided. In addition, the code | symbol 66 in FIG. 5 is a pipe which guides pressurized water or pressurized air to said supply port 59. FIG.

  As shown in FIG. 6, of the two attachment portions 53, 53 in the packing 1, one attachment portion 53 arranged on the shaft 60 side has a surface 53 a that contacts the inner peripheral surface 50 a of the cylindrical member 50. It is fixed in contact. As shown in FIG. 5, the other attachment portion 53 is folded back toward the rubber member 52, and the other surface 53 b is in contact with and fixed to the inner peripheral surface 50 a of the cylindrical member 50.

  That is, both attachment portions 53 and 53 of the packing 1 are arranged with their front end surfaces 53c and 53c directed toward the shaft 60 side. Accordingly, when the shield machine 61 is dug, the rubber member 52 that is in close contact with the shield machine 61 moves in a direction that is in a straight line with respect to the attachment portions 53 and 53, and thus the attachment portions 53 and 53 and the rubber member It can prevent that the boundary part with 52 is bent and damaged.

  As shown in FIG. 6, the fixing members 58 and 58 include first fixing members 58a and 58a and second fixing members 58b and 58b. The first fixing members 58 a and 58 a are provided with a recess 67 for inserting the attachment portion 53 on the surface facing the cylindrical member 50. A locking surface 67a is provided on the bottom surface of the recess 67 to lock one inclined surface 53d in the base portion of the mounting portion 53 formed in a wedge shape in cross section.

  On the other hand, the second fixing members 58b and 58b are disposed in the recesses 67 of the first fixing members 58a and 58a. The second fixing member 58b, 58b is inclined with respect to the cylindrical member 50 in order to engage the other inclined surface 53e at the base portion of the attachment portion 53 with the surface of the second fixing member 58b, 58b facing the first fixing member 58a, 58a. An inclined surface 69a is provided.

  Said 1st fixing member 58a and 2nd fixing member 58b are sufficient intensity | strength of the extent which is not deform | transformed or damaged with the tensile force which acts on the attachment part 53 from the rubber member 52 when the rubber member 52 of the packing 1 expand | swells. have.

  Further, a gap d1 that is substantially the same as the thickness t1 of the rubber member 52 is provided between the first fixing member 58a and the second fixing member 58b in order to allow the rubber member 52 to pass therethrough. The thickness (diameter) D of the retaining member 11 in the packing 1 is larger than the gap d1 between the first fixing member 58a and the second fixing member 58b.

  The fixing member 58 is fixed to the inner peripheral surface 50 a of the cylindrical member 50 by a bolt 71 and a cap nut 72.

When excavating the tunnel 62 to the side of the shaft 60 by the shield machine 61, the rubber member 52 and the cylindrical member 50 of the packing 1 are used to feed the tunnel 62 from the supply port 59 provided in the cylindrical member 50, as shown in FIG. 5. Pressure water having a predetermined pressure corresponding to the pressure of groundwater and earth and sand in the excavation portion of the tunnel 62 is supplied into the formed closed space 65.

  Then, as indicated by a two-dot chain line in FIG. 5, the rubber member 52 expands in a tire shape along the inner peripheral surface of the cylindrical member 50, and comes into close contact with the outer peripheral surface 61 a of the shield machine 61.

  Thereby, groundwater and earth and sand contained in the excavation part of the tunnel 62 can be prevented from flowing into the shaft 60 from the gap between the outer peripheral surface 61 a of the shield machine 61 and the inner peripheral surface 50 a of the cylindrical member 50.

  When the pressure of ground water and earth and sand in a tunnel excavation part is high, it is necessary to make the pressure P of the pressure water supplied in the closed space 65 high. And when the pressure of the pressure water supplied in the closed space 65 is increased, the tension generated in the rubber member 52 of the packing 1 increases, and the tension acting on the attachment portions 53 and 53 from the rubber member 52 increases. Power also increases.

  Here, in the present invention, the mounting portion 53, 53 of the packing 1 has a predetermined strength and a diameter D larger than the gap d1 between the first fixing member 58a and the second fixing member 58b as described above. Since the retaining member 11 is embedded, even if a large tensile force acts on the attachment portions 53 and 53 as described above, the retaining member 11 is not crushed, and the first fixing member 58a and the second fixing member 58b. The state locked between is maintained.

  Therefore, it is possible to prevent the attachment portions 53 and 53 from being detached from the fixing member 58 and to hold them in a predetermined position. Thereby, even when the pressure of groundwater and earth and sand in a tunnel excavation part is high, since the sealing function of the packing 1 can be maintained, it can prevent (suppress) that groundwater and earth and sand flow out into the vertical shaft 60 reliably.

  In addition, the water pressure of the pressure water supplied in the closed space 65 between the rubber member 52 and the cylindrical member 50 of the packing 1 is 1.3 times or more than the pressure of groundwater and earth and sand in the tunnel excavation part, as will be described later. Preferably, it is 1.5 times or more.

  In the above embodiment, the case where the sealing structure of the present invention is provided at the entrance of the tunnel 62 has been described. However, the present invention can also be provided at the exit of the tunnel 62. In this case, the front end surfaces 53c, 53c of the attachment portions 53, 53 in the packing 1 are arranged facing the opposite side to the shaft 60 provided at the tunnel exit. Thereby, it is possible to prevent the rubber member 52 moved together with the shield machine 61 from being bent and damaged at the boundary portion with the attachment portion 53.

  In the above embodiment, the case where only one packing 1 is provided has been described. However, as shown in FIG. 7, two packings 1A and 1B can be provided at a predetermined interval.

  By providing the two packings 1A and 1B with an appropriate interval in this way, even when one packing 1A enters the concave groove-shaped folded portion 70 in the shield machine 61, the other packing 1B is provided. Is in close contact with the outer peripheral surface 61a of the shield machine 61, so that the water stop performance as a whole is well maintained.

  In order to confirm the water stopping performance in the sealing structure of the present invention, as shown in FIG. 7, the water stopping performance in the sealing structure was confirmed using an actual shield machine 61 and the sealing structure of the present invention. In FIG. 7, the detailed structure is omitted, but each part in the sealing structure is the same as described above.

  The shield machine 61 has an outer diameter of 2,280 mm and a length of 5,000 mm. The cylindrical member 50 has an inner diameter of 2,640 mm and a length of 1,550 mm. The gap between the shield machine 61 and the cylindrical member 50 is w1 on one side and w2 on the other side, and a test was conducted when these gaps w1 and w2 were changed as described below.

  In this test, two packings 1A and 1B are arranged at an appropriate interval, pressure water having a pressure P0 corresponding to groundwater and earth and sand is supplied between these packings 1A and 1B, and the packings 1A and 1B. Pressure water having pressures PA and PB set according to the groundwater and earth and sand was supplied inside, and the water stopping performance of the packings 1A and 1B was confirmed.

<Test items>
(Case 1): The water stopping performance when P0 = 1.0 MPa and the eccentric amount X = 0 mm (w1 = 0, w2 = 0) with respect to the cylindrical member 50 of the shield machine 61 is confirmed.
(Case 2): The water stopping performance when P0 = 1.0 MPa and the eccentric amount X = 100 mm (w1 = 80 mm, w2 = 280 mm) with respect to the cylindrical member 50 of the shield machine 61 is confirmed.

<Test procedure>
1. Pressure water is supplied into the packings 1A and 1B, and the internal pressures PA and PB of the packings 1A and 1B are pressurized to about 0.5 MPa.
2. Pressure water is supplied between the packings 1A and 1B, and the pressure P0 between the packings 1A and 1B is increased to about 0.3 MPa.
3. The pressures PA and PB in the packings 1A and 1B and the pressure P0 between the packings 1A and 1B are in the relationship of 1 and 2 above (PA / P0 = PB / P0 = 0.5 / 0.3≈1.67). The pressure water is supplied to pressurize the pressures PA and PB in the packings 1A and 1B and the pressure P0 between the packings 1A and 1B until the pressure P0 between the packings 1A and 1B reaches 1.0 MPa. .
4). In a state where the pressure P0 between the packings 1A and 1B is maintained at 1.0 MPa, the shield machine 61 is advanced to check the water stoppage state by the packings 1A and 1B.
<Test results>
(Case 1) The pressure P0 = 1.0 MPa between the packings 1A and 1B, the eccentric amount X = 0 mm of the shield machine 61, and the pressures PA and PB in the packings 1A and 1B are slightly between 1.3 and 1.9 MPa. As a result of testing with different pressures, good water stopping performance was confirmed at any pressure.
(Case 2) The pressure P0 between the packings 1A and 1B is P0 = 1.0 MPa, the eccentric amount X of the shield machine 61 is 100 mm, and the pressures PA and PB in the packings 1A and 1B are slightly between 1.3 and 1.9 MPa. As a result of testing with different pressures, good water stopping performance was confirmed at any pressure.
Considering the above test results, the pressures PA and PB in the packings 1A and 1B are set to 1.3 times or more, preferably 1.5 times or more the pressure P0 between the packings 1A and 1B, that is, the pressure of groundwater and earth and sand. It is good.

It is a perspective view which shows the shield well seal packing of 1st Embodiment which concerns on this invention. It is a figure which shows the attachment part of the packing for shield wellhead sealing of 1st Embodiment which concerns on this invention, and is AA sectional drawing of FIG. It is sectional drawing which shows another attachment part of the packing for shield wellhead sealing of 1st Embodiment which concerns on this invention. It is sectional drawing which shows another attachment part of the packing for shield wellhead sealing of 1st Embodiment which concerns on this invention. It is sectional drawing which shows the shield wellhead sealing structure of 2nd Embodiment which concerns on this invention. It is sectional drawing which shows the fixing | fixed part which fixes the packing of 2nd Embodiment which concerns on this invention. It is a figure which shows the testing apparatus of the water stop performance confirmation test of 2nd Embodiment which concerns on this invention. It is sectional drawing which shows the shield wellhead sealing structure which concerns on a prior art example. It is a perspective view which shows the packing for shield wellhead sealing which concerns on a prior art example. It is sectional drawing which shows the attachment part of the packing for shield wellhead sealing which concerns on a prior art example.

Explanation of symbols

1, 1A, 1B Seal wellhead sealing packing 11 Retaining member 50 Tubular member 50a Tubular member inner circumferential surface 51 Packing 52 Rubber member 52a Rubber member inner circumferential surface 53 Mounting portion 53a Mounting portion surface 53b Mounting portion Back surface 53c Tip surface 53d of the mounting portion 53d One inclined surface 53e of the mounting portion 53e Other inclined surface of the mounting portion 54 Fiber reinforcing layer 55 Fiber member 56 Reinforcing fiber 57 Hard rubber 58 Fixing member 58a First fixing member 58b Second fixing member 59 Supply port 60 Vertical shaft 61 Shield machine 61a Outer peripheral surface of shield machine 62 Tunnel 65 Closed space 66 Pipe 67 Recessed portion of fixing member 67a Locking surface in recessed portion 69 Locking member 69a Inclined surface of locking member 70 Middle folding of shield machine Part 71 bolt 72 cap nut 75 ridge

Claims (4)

When a tunnel is excavated by a shield machine to the side of the shaft, groundwater and earth and sand contained in the ground to be excavated from the tunnel are introduced into the shaft from the gap between the outer peripheral surface of the shield machine and the inner peripheral surface of the tunnel. In order to prevent outflow, it is provided along the inner peripheral surface of a cylindrical member provided at the entrance or exit of the tunnel and having an inner diameter larger than the outer diameter of the shield machine. A tightly packed packing,
It has substantially the same length and a predetermined width as the inner peripheral length of the cylindrical member, is arranged along the inner peripheral surface of the cylindrical member, and is supplied by pressure water or pressure air supplied from the cylindrical member side. A band-shaped rubber member that expands toward the center of the cylindrical member;
A fiber reinforcement layer embedded over the entire surface of the rubber member;
The rubber member is provided at both end portions of the rubber member, has a thickness larger than that of the rubber member, is locked to a fixing member provided in the cylindrical member, and the fixing member and the cylindrical shape An attachment portion sandwiched between members and held in a predetermined position;
A shield well-sealing packing having a predetermined rigidity and strength and having a wall thickness larger than that of the belt-shaped rubber member and embedded in the mounting portion .   The shielding wellhead sealing packing according to claim 1, wherein the retaining member is a linear member made of steel or resin.   The fiber reinforcing layer is formed by two layers of fiber members laminated, the two layers of fiber members are separated inside the mounting portion and arranged at a predetermined interval, and these separated two layers 3. The shield well sealing seal according to claim 1, wherein different reinforcing fibers are laminated on each of the fiber members. A shield wellhead sealing structure using the shield well seal packing according to any one of claims 1 to 3,
A cylindrical member provided at the entrance or exit of the tunnel and having an inner diameter larger than the outer diameter of the shield machine;
A fixing member that is fixed at a predetermined position of the tubular member, the attachment portion in the shield wellhead packing is locked, and a fixing member that sandwiches the attachment portion in cooperation with the tubular member;
Provided in the cylindrical member to supply pressurized water or pressurized air having a predetermined pressure into a closed space formed between the inner peripheral surface of the cylindrical member and the rubber member in the packing. A supply port,
Of the mounting portions in the packing, one of the mounting portions is fixed with one surface abutting against the inner peripheral surface of the tubular member, and the other mounting portion is folded back to the other surface. Is fixed in contact with the inner peripheral surface of the cylindrical member.

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