JP6537238B2 - Concrete formwork structure - Google Patents

Description

  The present invention relates to a concrete formwork structure, and more particularly to a formwork structure provided with a water permeable sheet.

  It is known that curing of concrete cast by covering the surface of a mold with a water-permeable sheet removes excess water and air bubbles in the concrete and improves the strength and quality of the concrete. Therefore, for example, Patent Document 1 proposes fixing a water-permeable sheet to a mold with a fixing sheet comprising a water-absorbent resin-impregnated nonwoven fabric layer and a pressure-sensitive adhesive layer. However, in this structure, it takes time and effort to install the water-permeable sheet, and there is a problem that fixation by adhesion is not reliable. Therefore, Patent Document 2 proposes a structure in which mounting pieces are provided at appropriate positions on the edge of the water-permeable sheet, and the water-permeable sheet is covered on the outer surface of the mold by pulling the mounting pieces.

Japanese Patent Application Laid-Open No. 2007-85120 JP 2012-229546

  By the way, the concrete form for secondary lining concrete in the tunnel has an arch shape in which a concrete injection space is formed between it and the inner wall of the tunnel. In this case, the concrete cast at the lower end of the lower end of the above-mentioned form Excess water and air bubbles are easily accumulated inside. Then, in order to drain these surplus water etc. promptly, it is required to install a water-permeable sheet. However, in the above-described conventional structure for pulling the attachment piece, there is a problem that the water-permeable sheet is easily wrinkled or twisted and the function of the water-permeable sheet is not fully exerted.

  Therefore, the present invention solves such a problem, and it is possible to simply and surely stretch the water permeable sheet in the formwork, and to prevent the generation of wrinkles and twist when the tension sheet is stretched, and the function of the water permeable sheet is sufficiently made. It aims at providing the concrete formwork structure which can be made to demonstrate.

In order to achieve the above object, according to the first aspect of the present invention, there is provided a concrete formwork structure in which an outer surface is faced to a concrete injection space, and a first rod body installed at one end of the concrete formwork; A water-permeable sheet, one edge of which is attached to the first rod along the rod and arranged to cover the outer surface, and the other edge of the water-permeable sheet is attached along its longitudinal direction and a second rod, Ri Na and stretched the permeable sheet on said outer surface in a state in which the second rod is pulled inwardly of the concrete form, folded other edge of the permeable sheet The second rod is inserted into and attached to the inside of the cylinder .

According to the first aspect of the present invention, since the second rod to which the other edge of the water-permeable sheet is fixed is pulled against the first rod to which one edge of the water-permeable sheet is fixed. In the installed state, the water-permeable sheet is not wrinkled or twisted, and the function can be sufficiently exhibited. In addition, the second rod can be easily attached to the water-permeable sheet.

In the second aspect of the present invention, the lower form (33) is formed into an arch shape in which a predetermined concrete injection space (C) is formed between the inner wall and the tunnel, and the foam on both sides constituting the arch shape is divided up and down. ) And the upper foam (32) The secondary lining concrete of the tunnel which made the outer circumference side of these foams relatively separated or approachable around the connecting shaft (34) provided on the inner circumference side of these foams. It is a concrete formwork structure in a formwork, and the first rod (51) which fixed the upper edge of the water permeable sheet (4) is installed on the upper end of the lower side foam (33) as a concrete formwork And fold the lower edge (42) of the water-permeable sheet (4) into a cylindrical shape, insert and mount the second rod (52) in the cylinder, and insert the second rod (52). Inner circumference of lower foam (33) In a state of pulling to the direction formed by the stretched water permeability sheets (4) on the outer peripheral surface of the lower form (33).

  According to the fourth aspect of the present invention, the water-permeable sheet is simply and reliably installed in the lower part on both sides of the secondary lining concrete formwork of the tunnel simply and reliably and without any wrinkles, etc. Strength and quality can be improved.

  The reference numerals in the parentheses indicate the correspondence with the specific means described in the embodiments to be described later.

  As described above, according to the concrete formwork structure of the present invention, the water-permeable sheet can be simply and reliably stretched on the formwork, and the function of the water-permeable sheet is sufficiently prevented by preventing the generation of wrinkles and twists when stretched. Can be

It is a cross-sectional view of the slide center for tunnels in 1st Embodiment of this invention. FIG. 5 is an enlarged cross-sectional view of the lower end foam portion of the slide centerle formwork. FIG. 5 is an enlarged cross-sectional view of the lower end foam connection. It is a perspective view of the lower edge of a permeable sheet. It is a side view of a holding tool. It is an expanded cross-sectional view of the lower end foam | form part in 2nd Embodiment of this invention. It is a side view of a hook member.

  The embodiments described below are merely examples, and various design improvements made by those skilled in the art without departing from the scope of the present invention are also included in the scope of the present invention.

First Embodiment
FIG. 1 shows a cross section of a tunnel slide center provided with the concrete formwork structure of the present invention. In FIG. 1, the slide center 1 is provided with a portal type gantry 2 capable of passing through a vehicle, and the gantry 2 supports an arch-shaped mold 3 disposed so as to cover the upper half thereof. Then, a space C for injecting secondary lining concrete is formed between the outer peripheral wall of the form 3 and the inner peripheral wall of the tunnel T (more precisely, the inner peripheral wall of the primary lining concrete).

  The gantry 2 has a fixed length in the front-rear direction perpendicular to the paper surface, and wheels 22 are provided at the lower ends of the legs 21 at the front and rear ends thereof, and are positioned on the rails 23. Further, an auxiliary jack 25 is provided at the lower end of each of the plurality of legs 24 located in the middle of the gantry 2 in the front-rear direction. The left and right halves of FIG. 1 are cross sections at different positions in the gantry longitudinal direction.

  The formwork 3 is formed by connecting a plurality of identical formwork members having a constant width in the front-rear direction, and each formwork member rotates around the lower end surfaces of the top end foam 31 and the top end foam 31 located at the top. It comprises a side foam 32 which is movably connected and located on both sides, and a lower end foam 33 which is pivotally connected to the lower end of the side foam 32. The top end foam 31 is vertically movably supported by a plurality of jacks (not shown) provided in the front-rear direction on the top of the gantry 2. Further, the side foam 32 and the lower foam 33 are connected to the lower portion of the main body of the gantry 2 by jacks 26 and 27, respectively, and are rotated in the inside and outside.

  An enlarged view of the lower end portion of the right side foam 32 is shown in FIG. In FIG. 2, a hinge piece 331 provided at the upper end of the lower end form 33 is rotatably connected to the side form 32 by a shaft member 34 at a hinge piece 321 provided at the lower end. Thus, the lower end foam 33 can be rotated clockwise with respect to the side foam 32 about the connecting shaft 34 in FIG.

  As shown in FIG. 3, the circumferential lower end surface 323 of the skin plate 322 constituting the outer peripheral surface of the side foam 32 and the circumferential upper end surface 333 of the skin plate 332 constituting the outer peripheral surface of the lower end foam 33 I am in touch. The lower end surface 324 of the side foam 32 and the upper end surface 334 of the lower end foam 33 face each other at an interval with the end surfaces 323 and 333 of the skin plates 322 and 332 in contact with each other. A part is recessed to form a housing space S.

  When the jack 27 (FIG. 1) is contracted, the lower end foam 33 is rotated clockwise about the connecting shaft 34, and the end faces 323 and 333 are separated to form a constant gap therebetween. . In the state of FIG. 3 in which the lower end foam 33 is pivoted to the outer end, the skin plate 322 of the side foam 32 and the skin plate 332 of the lower end foam 33 are flush with each other with their end faces close to each other.

  Here, the water-permeable sheet 4 (FIG. 3) having a sufficient width (vertical direction in FIG. 2) to cover the skin plate 332 of the lower end foam 33 is provided. As the water-permeable sheet 4, a commercially available water-permeable release sheet for formwork can be used. The upper edge 41 of the water-permeable sheet 4 is processed into a cylindrical shape as shown in FIG. 3, and the rod 51 is inserted into the cylinder. The upper edge 41 thus substantially thickened abuts on the overhanging portion 335 of the opening edge of the accommodation space S and is locked there, and the middle portion of the water-permeable sheet 4 near the upper edge 41 Is sandwiched between the end faces 323 and 333 of the skin plates 322 and 332 adjacent to each other.

  The water-permeable sheet 4 extends downward over the surface of the skin plate 332 of the lower end foam 33 (FIG. 2), and the lower edge 42 thereof is bent inward of the lower end foam 33 at the lower end of the skin plate 332 and diagonally upward There is. The lower edge 42 of the water-permeable sheet 4 is folded back as shown in FIG. 4 and is sewn into a tubular shape extending in the longitudinal direction (left and right direction in FIG. 4) to form a mounting portion 421. The rod 52 is inserted into the mounting portion 421. When the bar 52 is inserted, the lower edge 42 of the water-permeable sheet 4 having a substantially circular cross-section is held by the holding tool 6 (FIG. 2) at a required position in the longitudinal direction.

  As shown in FIG. 5, the holding tool 6 has a bolt shaft 63 at the middle portion of a pair of cross-arranged arm portions 61 and 62 (in fact, each arm portion is constituted by a parallel plate having the same shape). The outer periphery of the lower edge 52 of the water-permeable sheet 4 is gripped and held by arc-shaped gripping portions 611, 621 formed at the tips of both arms 61, 62. The bolt pin body 65 is detachably inserted into the stop holes of both the arm portions 61 and 62 so that both the arm portions 61 and 62 can be held in the closed state shown in FIG.

  A locking tool 72 provided at one end of the chain 71 (FIG. 2) is locked by a bolt 64 provided at the base end of the arm portion 61 of the holding tool 6. The other end of the chain 71 is provided with a known clamp 73 provided with a reciprocating handle 731 and its hook 732 is engaged with the annular locking member 351 of the beam 35 protruding from the inner periphery of the side foam 32. It is done. When the chain 71 is pulled by the clamp 73, the water-permeable sheet 4 is stretched so as to cover the surface of the skin plate 332 of the lower end foam 33.

  When the water-permeable sheet 4 is installed on the skin plate 332 of the lower end foam 33, the jack 26 (FIG. 1) is contracted to rotate the lower end foam 33 clockwise about the connecting shaft 34 in FIG. And the skin plate end faces 323 and 333 (FIG. 3) of the lower end foam 33 are separated to form a constant gap therebetween. Then, the upper edge 41 of the water-permeable sheet 4 is inserted into the housing space S from the above-mentioned gap together with the rod body 51 inserted therein and locked to the overhang portion 335

  Thereafter, the jack 26 is extended and the lower end foam 33 is returned and rotated to bring the end faces 323 and 333 close to each other and hold an intermediate portion close to the upper edge 41 of the water permeable sheet 4 (state of FIG. 3) . In this state, the general part of the water-permeable sheet 4 is dropped downward so as to cover the surface of the skin plate 332 of the lower end foam 33. At this time, since the cylindrically formed mounting portion 421 is formed at the lower edge 42 of the water-permeable sheet 4 and the rod 52 is inserted therein, the lower edge of the dropped water-permeable sheet 4 is twisted. There is no wrinkles or twisting, and the water-permeable sheet 4 always maintains a flat state and covers the surface of the skin plate 332.

  In this state, the lower edge 42 of the water-permeable sheet 4 is bent inward at the lower end of the skin plate 332 and pulled upward along the lower end face of the lower end foam 33, and the required location in the longitudinal direction of the lower edge 42 as described above The sheet is held by the holding tool 6 and the water permeable sheet 4 is stretched by the clamping machine 73 through the chain 71. Also in this case, since the water-permeable sheet 4 is restricted in deformation by the rod 52 into which the lower edge 42 is inserted, it is possible to prevent the water-permeable sheet 4 from being wrinkled or twisted. Thereafter, an intermediate portion near the lower edge 42 of the water-permeable sheet 4 is fixed to a crosspiece 36 (FIG. 2) provided in the lower end face of the lower end foam 33 by a tacker at an appropriate place. Thereafter, the gripping by the gripping tool 6 is released.

  When the secondary lining concrete is poured into the space C (FIG. 1), excess water and air bubbles are easily accumulated in the concrete located on the outer side of the lower end portions of both sides of the form 3. Here, in the present embodiment, since the water permeable sheet 4 is stretched around the outer periphery of the lower end foam 33 located at the lower end portions of both sides of the formwork 3, excess water etc. in the concrete is efficiently discharged through the water permeable sheet 4 Be done. At this time, the middle portion of the water-permeable sheet 4 near the upper edge 41 is sandwiched between the end faces 323 and 333 of the skin plates 322 and 332 of the side foam 32 and the lower end foam 33, and the sheet general surface is the outer peripheral surface of the lower end foam 33 As the rod 52 held by the lower edge 42 of the sheet is pulled, the water permeable sheet 4 is not wrinkled or twisted, and its function is fully exerted.

Second Embodiment
Instead of fixing the middle portion near the lower edge 42 of the water-permeable sheet 4 to the crosspiece 36, the water-permeable sheet 4 may be stretched and held on the lower end foam 33 with a structure as shown in FIG. That is, in FIG. 6, the hook member 81 is fitted in advance at an appropriate position in the longitudinal direction of the outer periphery of the cylindrical lower edge 42 of the water-permeable sheet 4 in which the rod 52 is inserted. As shown in FIG. 7, the hook member is formed of a substantially circular plate having holding portions 812 and 813 extending in a symmetrical arc shape from the base portion 811, and is provided in the locking hole 814 provided in the base portion 811. A locking tool 821 provided at one end of the belt 82 (FIG. 6) is locked. On the other hand, a belt 83 having one end connected to a bracket 331 located at the upper end of the lower end foam 33 corresponding to the belt 82 is provided, and a known ratchet 84 for clamping belt is attached to the tip of the belt 83 ing.

  According to such a structure, after the water permeable sheet 4 is stretched by the clamp 73 (FIG. 2), the other end of the belt 82 is inserted into the ratchet 84 for clamp belt, and the ratchet 84 is operated to operate the belt By pulling 82, the water-permeable sheet 4 is stretched around the lower end foam 33, as shown in FIG. Also in this case, since the rod 52 provided along the lower edge 42 of the sheet is pulled, the water-permeable sheet 4 is not wrinkled or twisted. Further, according to the present embodiment, by removing the belt 82 from the ratchet 84, the used water-permeable sheet 4 can be easily replaced with a new water-permeable sheet.

(Other embodiments)
In each of the above embodiments, the upper edge 41 of the water-permeable sheet 4 is locked to the overhang portion 335 in the accommodation space S, but the locking structure is not particularly limited. Further, the rod 51 is constituted by a rotating shaft fixedly supported at the upper end portion of the lower end form 33 without using the locking structure, the upper edge 41 of the water permeable sheet 4 is wound around the rotating shaft, and the water permeable sheet 4 is It is also possible to have a structure that can be extended. Moreover, the structure which pulls the rod 52 of the lower edge 42 of the water-permeable sheet 4 is not restricted to the thing as described in said each embodiment, either. Furthermore, the lower edge 42 of the water-permeable sheet 4 does not necessarily have to be formed into a cylindrical shape, and a mounting portion with some structure for mounting the rod 52 may be provided. Further, the lower edge 42 may be directly wound around the rod 52 and fixed without providing a mounting portion. Although each said embodiment demonstrated the case where this invention was applied to the form of a tunnel center, this invention can be applied also to the upper form frame surface of a general form, an inclined form surface, etc.

  DESCRIPTION OF SYMBOLS 3 ... formwork 32 ... side foam (upper side foam), 33 ... lower end foam (lower side foam), 4 ... water-permeable sheet, 41 ... upper edge (one edge), 42 ... lower edge (other edge), 421 ... mounting Part, 51: rod body (first rod body) 52: rod body (second rod body) C: concrete injection space.

Claims (2)

A concrete form structure having an outer surface facing a concrete injection space, comprising: a first rod installed at one end of the concrete form; and one end of the first rod along the first rod. A water-permeable sheet fixed to the body and disposed to cover the outer surface, and a second rod fixed to the other end of the water-permeable sheet along its longitudinal direction, the second rod body of Ri in a state of pulling inward the concrete form name and stretched the permeable sheet on said outer surface, said other end of the folded back cylindrical shape to the said second tubular shaped water-permeable sheet Concrete formwork structure inserted and fitted with a rod . It forms an arch shape that forms a predetermined concrete injection space between it and the inner wall of the tunnel, divides the foam on both sides of the arch shape into upper and lower, and forms the lower and upper foams on the inner periphery of these foams. A concrete form structure in a formwork for secondary lining concrete of a tunnel in which the outer periphery side of these foams can be relatively separated or approached around the connecting shaft provided, and the upper edge of the water permeable sheet is The fixed first rod is placed at the upper end of the lower foam as a concrete form, and the lower edge of the water-permeable sheet is folded back to form a tube, and the second rod is placed in the tube. The concrete formwork structure formed by tension-installing the said water-permeable sheet on the outer peripheral surface of the said lower side foam in the state which insert-mounted and pulled the said 2nd rod to the inner peripheral direction of the lower side foam | form.

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