JP2008063734A - Waterproof sheet for tunnel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a waterproof sheet for a tunnel preventing the waterproof sheet from being damaged, or torn, even by the load of ready mixed concrete placed in secondary lining with no loss in waterproof sheet spreading and extending work performed while adding. <P>SOLUTION: A plurality of fins 4, 40 arranged to the waterproof sheet 1 to spread the waterproof sheet 1 on a primary lining surface f1 are positioned at suitable spaces along the longitudinal direction of the tunnel. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a tunnel waterproof sheet, and more particularly to a tunnel waterproof sheet suitable for spreading on a primary lining surface in a NATM method.

The so-called NATM construction method is sometimes used for tunnel construction in mountains, underground, and seabeds. The NATM method is that before the rock after excavation begins to loosen, concrete material is sprayed onto the exposed ground surface, a steel support is built, and a rock bolt is placed to form the primary lining surface. This is a construction method in which a waterproof sheet material is spread on the surface, and then the concrete is laid down and a concrete lining is applied to cover the waterproof sheet, and then secondary lining is applied. Improve sexiness.

  In the case of secondary lining, it is necessary to spread the waterproof sheet on the primary lining surface, but as a method that can be applied without drilling holes in the waterproof sheet, one end is free and the other end is fixed to the waterproof sheet. A method has already been proposed in which a flexible strip-shaped sheet material (hereinafter referred to as fin) is fixed to the primary lining surface on the free end side with a nail or the like.

  However, the above-mentioned conventional fins are arranged on the back surface of the waterproof sheet along the circumferential direction of the tunnel. As described above, the primary lining surface is supported by being bent and buried in the H-shaped steel along the circumferential direction of the tunnel. A part of the work protrudes intermittently along the length of the tunnel, and when extending the waterproof sheet, if the position of the fin overlaps with the support work, a fixing member such as a nail cannot be driven. For this reason, the waterproof sheet is largely retracted onto the waterproof sheet on the front side to shift the position of the fins, that is, the sheet is welded after a large allowance between the waterproof sheets is taken, resulting in sheet waste.

Moreover, in the secondary lining, the primary lining surface covered with the waterproof sheet is further reinforced with concrete, but at this time, the waterproof sheet must be spread without gaps along the unevenness of the primary lining surface, If the sheet is tightly stretched with respect to the recess, the sheet may be pressed and damaged, cracked, or the like by the load of the placed concrete. In addition, the secondary lining concrete that starts to accumulate from below the space formed by the primary lining surface and the formwork pulls the hem of the sheet and exerts tension on the entire sheet, and the affected part of the waterproof sheet is already fixed The work still has problems, as it may delaminate from the primary lining surface.
JP-A-8-303193 JP 2000-54800 A

  In view of the above problems, the present invention has no loss in the spreading and extending work of the waterproof sheet to be added, and the waterproof sheet is also applied by the load of ready-mixed concrete to be cast in the secondary lining It is an object of the present invention to provide a tunnel waterproof sheet that is prevented from being damaged or broken.

  The structure of the waterproof sheet for a tunnel of the present invention made for the purpose of solving the above-mentioned problem is that a plurality of fins arranged on the waterproof sheet are arranged in the tunnel length direction in order to spread the waterproof sheet on the primary lining surface. It is characterized in that it is positioned with an appropriate interval along.

  Since the present invention is positioned along the tunnel length direction of a plurality of fins disposed on the waterproof sheet in tunnel construction, the fins can be fixed to the primary lining surface regardless of the position of the projecting support, The overlap allowance for overlapping the sheets at the joint between the waterproof sheets can be set as designed, and wasteful use of the waterproof sheets can be avoided. In addition, since the waterproof sheet can be spread while following the uneven primary lining surface without any gaps, the waterproof sheet will not be damaged or broken even by the load of the secondary lining concrete that has been placed. It has the effect of being able to be constructed while ensuring aqueous properties.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view illustrating a main part of an example of a waterproof sheet for tunnel according to the present invention, FIG. 2 is a perspective view illustrating the main part of a conventional tunnel waterproof sheet, and FIG. 3 is a fin of the waterproof sheet of the present invention. FIG. 4 is a side end view schematically illustrating the state where the fin of the conventional waterproof sheet is fixed to the primary lining surface, and FIG. It is the side end figure which expanded and illustrated typically the waterproof sheet and secondary lining concrete stuck on the primary lining surface.

  In FIG. 1, 1 is an example of the waterproof sheet for a tunnel according to the present invention, and a water-stopping material 2 that blocks water from the excavated natural ground surface f0 (see FIGS. 3 to 4), and the water-stopping material. 2 is composed of two layers of cushioning material 3 that protects the unevenness of the primary lining surface f1. In this embodiment, the water stop material 2 is formed of a sheet material having a thickness of about 0.8 mm made of an ethylene vinyl acetate copolymer as an example, and is bonded to the buffer material 3 at an appropriate location on the primary lining surface f1 side. Are integrated. The thickness design of the water blocking material 2 is appropriately determined from the balance between the certainty at the time of thermal welding of the waterproof sheet 1 and the difficulty at the time of work due to its weight, and is desirable setting in this embodiment. Although 0.8 mm is selected as the value, the design is not limited to this, and the value may be 0.8 mm or more, or 0.8 mm or less. In addition, since the water-stopping material 2 is only required to have water-blocking properties, synthetic resin materials such as polyvinyl chloride (PVC), ethylene copolymer / buchimen (ECB), rubber, artificial leather, etc. However, it is desirable to use a material that can be welded by electromagnetic heat or the like so as to overlap and extend. In addition, as will be described later, the technique of the present invention can be applied to a so-called separation-type sheet in which the water blocking material 2 and the buffer material 3 are separately applied, and two-layer integrated like the waterproof sheet of this embodiment. It is not limited to a simplified form. Incidentally, the vertical direction of FIGS. 1 and 2 is along the circumferential direction of the tunnel, and the horizontal direction is along the length direction of the tunnel.

  The cushioning material 3 is formed of a nonwoven fabric layer having a thickness of about 3 to 5 millimeters, and is bonded or heat welded to the primary lining surface f1 side of the waterproof sheet 1 with an adhesive or the like. The primary lining surface f1 is extremely uneven due to the sharp cross section of the exposed rock bolt L and the unevenness of the sprayed concrete material C1, but the nonwoven fabric layer can withstand this without being damaged as a cushioning material. It takes a thing. In addition, the thickness of a nonwoven fabric layer is not restricted to 3-5 millimeters, It is arbitrary to design to 3 millimeters or less, or 5 millimeters or more.

  Before placing the secondary lining concrete, it is necessary to spread the waterproof sheet 1 on the primary lining surface f1 while maintaining water shielding. In order to construct the sheet without making a hole, a so-called fin member is used. The method using is effective. For this purpose, a fin member 4 for attaching the waterproof sheet 1 to the primary lining surface f1 is attached to the cushioning material 3. The fin 4 is formed of the same non-woven fabric as the cushioning material 3, but may be formed of woven fabric, synthetic resin, rubber, leather or other materials as long as the material can withstand tension and tearing. Further, in the case of a separation type sheet in which the water blocking material 2 and the buffer material 3 are not bonded and integrated, the fin 4 is directly fixed to the water blocking material 2 (not shown), and first to the primary lining surface f1. The waterproof sheet 1 can be spread without damaging the water blocking material 2 by fixing the fins 4 to the fixed cushioning material 3.

  The waterproofing material 2 and the buffer material 3 of the present embodiment are not attached in the left and right end regions of about 200 to 250 millimeters of the waterproof sheet 1 and are separated from each other. As a result, the waterproofing material 2 can overlap the left and right end regions with the overlap margin 5, and the waterproof sheet 1 can be tunneled by being overlapped (laminated) or welded together (in a palm type). Can extend in the length direction. In this embodiment, the fins 4 are formed slightly shorter or substantially the same length as the width of the waterproof sheet 1 so as not to hinder the heat welding operation in the overlap margin 5 between the waterproof sheets 1 (see FIG. 1). ). Alternatively, the fins 4 may be formed so as to be free without being fixed to the waterproof sheet 1 at at least one edge portion of the waterproof sheet 1 so as to avoid an obstacle to the heat welding operation.

  On the other hand, in the conventional waterproof sheet 10, as illustrated in FIG. 2, the fin 40 is attached along the circumferential direction of the tunnel. For this reason, for example, when extending the waterproof sheet 10 from the wellhead side, if the fin 40 overlaps with the steel support described above, it cannot be fixed with a nail or the like. As already mentioned, it was inevitable that the overlap allowance 50 would have to be taken extra.

  Further, since the conventional waterproof sheet 10 is merely attached to the left and right end regions of the fin 40 and the cushioning material 30 along the circumferential direction of the tunnel with respect to the primary lining surface f1, the sheet 10 is spread without any gap. It is difficult to do (see FIG. 5). For this reason, as described above, the conventional waterproof sheet 10 pressed against the uneven portion of the primary lining surface f1 by the placement of the secondary lining concrete C2 has been damaged and broken. is there.

  Therefore, in the tunnel waterproof sheet 1 of the present invention, as illustrated in FIG. 1, the fins 4 are arranged along the tunnel length direction with respect to the buffer material 3 (or directly with respect to the water blocking material 2). As a result, the above-described problems have been solved, and this point will be described below with reference to FIGS.

  The waterproof sheet 1 of the present invention illustrated in FIG. 1 includes fins 4 along the tunnel length direction toward the primary lining surface f1 side of the cushioning material 3, and the left and right end regions thereof have an overlap margin 5. Can be welded and extended. The fin 4 has a vertical width of about 10 to 20 centimeters in FIG. 1 and a length that is substantially the same as or slightly shorter than the waterproof sheet 1, and one end of the vertical width is fixed to the cushioning material 3. The edge is free. For this reason, even if the sheet 1 meets the support in the spreading of the waterproof sheet 1, it can be fixed to the primary lining surface f1 with a nail or the like at the position across the support in each fin 4. 2 is not harmful, and there is no waste caused by the position of the fin 40 of the conventional sheet 10 in FIG.

  In the present embodiment, the design is such that the total number of fins 4 is about 20 for a tunnel having an inner peripheral length of about 20 meters, and the fins 4 are attached at intervals of about 1 meter. And since the several fixing member 7 can be arrange | positioned along the tunnel length direction in the fin 4, the fixing location required in order to spread the waterproof sheet 1 without gap, following the primary lining surface f1, A sufficient number and free positions can be secured in both the tunnel circumferential direction and the length direction. Thereby, it can avoid that the waterproof sheet 1 will be in the state stuck to the primary lining surface f1 which is not landed, As a result, the said sheet | seat 1 is damaged by the load of secondary lining concrete C2, a tear, etc. To stop doing. Further, since the waterproof sheet 1 can be spread on the primary lining surface with more fastening members 7 than the conventional sheet 10, the waterproof sheet 1 having a large fixing force exerted by the secondary lining concrete C2 thereby. The primary lining surface f1 is not peeled off even by the tension.

  Further, if the fixing force per waterproof sheet can be increased, the size per sheet can be increased and fixed. As a result, when the conventional sheet 10 is processed with a length of about 2 meters (width in the front-rear direction) along the tunnel length direction per sheet, in the waterproof sheet 1 of the present invention, 4 sheets per sheet. It was possible to form and construct with about ~ 6 meters. As a result, the number of welded locations per unit area on the inner wall of the tunnel can be greatly reduced, the work burden on the site can be reduced, and the water shielding by the waterproof sheet 1 can be kept high.

  In addition, when the sheet is wound along the circumferential direction of the tunnel, the conventional waterproof sheet 10 is wound in a spindle-shaped unstable state in which the intermediate portion in the sheet width direction bulges due to the arrangement structure of the fins 40. The waterproof sheet 1 can be wound with a more stable shape than the conventional sheet 10 because the fins 4 are arranged in the tunnel length direction, and is excellent in handling during work and transportation. For the same reason, even in the so-called bellows folding in which the sheet is folded in a zigzag manner, the waterproof sheet 1 of the present invention can provide a stable folded state, so that the waterproof sheet 1 can be smoothly spread out. It has high practicality.

  The present invention is as described above, and in order to spread the primary lining surface and the waterproof sheet in the tunnel construction, a plurality of fins disposed on the waterproof sheet are positioned along the tunnel length direction. It was installed because the fins can be fixed without being affected by the position of the steel support projecting to the primary lining surface, and the waterproof sheet can be spread while following the uneven primary lining surface without any gaps. The waterproof sheet is not damaged or cracked even by the load of the secondary lining concrete, and can be constructed while maintaining a high water-blocking property. Therefore, the waterproof sheet is extremely useful as a tunnel waterproof sheet.

The perspective view which showed the principal part of an example of the waterproof sheet for tunnels which concerns on this invention The perspective view which illustrated the principal part of the conventional waterproof sheet for tunnels Side end view schematically illustrating a state in which the fin of the waterproof sheet of the present invention is fixed to the primary lining surface Side end view schematically illustrating a state where fins of a conventional waterproof sheet are fixed to a primary lining surface Side end view schematically exemplifying a waterproof sheet and secondary lining concrete stuck to the primary lining surface

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 This invention waterproof sheet 10 Conventional type waterproof sheet 2,20 Waterproof material 3,30 Buffer material 4,40 Fin 5,50 Overlap allowance 6 Formwork 7 Fastening member L Lock bolt f0 Ground mountain surface f1 Primary lining surface f2 Two Secondary lining surface C1 Primary lining concrete C2 Secondary lining concrete

Claims (5)

  A tunnel waterproof sheet, wherein a plurality of fins are arranged at appropriate intervals along the tunnel length direction of the waterproof sheet in order to spread the waterproof sheet on the primary lining surface. Waterproof sheet.   The waterproof sheet for tunnels according to claim 1, wherein the waterproof sheet has the fin fixed to a water stop material of the waterproof sheet.   The waterproof sheet for tunnel according to claim 1, wherein the waterproof sheet has the fin fixed to a cushioning material of the waterproof sheet.   The length of the fin in the tunnel length direction is substantially the same as that of the waterproof sheet, and is free with respect to the waterproof sheet at least at one end edge of the waterproof sheet, or slightly shorter than the waterproof sheet. Item 1. The waterproof sheet for tunnel according to any one of Items 1 to 3.   The waterproof sheet for tunnel according to any one of claims 1 to 4, wherein the cushioning material is a nonwoven fabric.

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