Spalling prevention structure

Abstract

To prevent a presser for pressing a mesh sheet and an expansion anchor for mounting the presser from falling off a concrete structure.SOLUTION: A spalling prevention structure includes a spalling prevention material 10 in which a lattice-shaped shape retainer 12 is layered and fixed on a mesh sheet 11, and a comb-shaped retainer 30 in which a front plate 31 is provided with a front through hole 36 through which an expanded expansion anchor cannot slip out and a plurality of comb teeth 32 are provided at a position that is folded back from the front plate 31 so as not to overlap with the front through hole 36. The spalling prevention material 10 is laid so as to substantially follow a mounting surface 101 of a concrete structure 100. Each comb tooth 32 of the comb-shaped retainer 30 is arranged on the mounting surface 101 side through a mesh 111 of the mesh sheet 11. A shape retainer 122 is accommodated in a pressed state in a protruding step portion 34. The expansion anchor is cast into the concrete structure 100 through the front through hole 36. The front plate 31 is pressed against the mesh sheet 11 side by a nut 51.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a spalling prevention structure that prevents spalling of the surface of a concrete structure such as a tunnel. [Background technology]

[0002] Conventionally, there is a spalling prevention structure described in Patent Document 1 as a structure for preventing the falling of pieces peeled off from the surface of a concrete structure that has deteriorated over time. In this spalling prevention structure, a planar spalling prevention material is formed by a net-like mesh sheet and a lattice-like shape retainer that is overlaid and fixed to one side of the mesh sheet, and the mesh sheet of the spalling prevention material is placed on the mounting surface side of the concrete structure and laid along the mounting surface. Then, a flat pressing plate is pressed toward the mounting surface side by a nut screwed onto an anchor that has been installed in the concrete structure, and the step part of the pressed pressing plate presses the shape retainer of the spalling prevention material toward the mounting surface side, and the spalling prevention material is attached to the concrete structure. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-111954 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, because spalling prevention structures for concrete structures are usually installed on deteriorated and weakened concrete, in a configuration such as the spalling prevention structure of Patent Document 1, in which an anchor and nut are cast into the deteriorated concrete to press a flat pressure plate against the spalling prevention material, there is a risk that the cast anchor may come loose from the deteriorated concrete, causing both the loosened anchor and the flat pressure plate to fall.

[0005] The present invention has been proposed in consideration of the above-mentioned problems, and aims to provide a spalling prevention structure and a comb-shaped clamp that can prevent a clamp that holds down a mesh sheet laid roughly along a concrete structure and an expansion anchor to which the clamp is attached from falling off the concrete structure. [Means for solving the problem]

[0006] The anti-spare structure of the present invention comprises an anti-spare material in which a lattice-shaped shape-retaining body is overlaid and fixed to a mesh sheet, and a comb-shaped clamp which is folded back at a fold-back portion from a front plate having a front through hole through which an expanded expansion anchor cannot escape, and has multiple comb teeth provided at a position that does not overlap with the front through hole, and a protruding step portion formed adjacent to the fold-back portion of the front plate, and is characterized in that the anti-spare material is laid so as to roughly follow the mounting surface of the concrete structure, each of the comb teeth of the comb-shaped clamp is arranged on the mounting surface side through the mesh of the mesh sheet, the shape-retaining material constituting the shape-retaining body is accommodated in the protruding step portion of the comb-shaped clamp in a pressed state, the expansion anchor is driven into the concrete structure through the front through hole of the comb-shaped clamp, and the anti-spare material is attached so that the front plate of the comb-shaped clamp is pressed against the mesh sheet side by a nut screwed onto the expansion anchor. According to this, the expansion anchor in the expanded state cast into the concrete structure cannot slip out of the comb-shaped retainer, and by arranging each comb tooth of the comb-shaped retainer on the mounting surface side through the mesh of the mesh sheet, it is possible to prevent the expansion anchor in the expanded state from slipping out of the concrete structure and falling together with the comb-shaped retainer. In other words, it is possible to prevent the comb-shaped retainer that holds down the mesh sheet laid so as to substantially conform to the concrete structure and the expansion anchor to which the comb-shaped retainer is attached from falling off the concrete structure. In addition, each comb tooth of the comb-shaped retainer is arranged on the mounting surface side through the mesh of the mesh sheet, and it is possible to install it at any position where the shape retaining material can be accommodated in a pressed state in the protruding step portion, and the degree of freedom in the installation position of the retainer that holds the spalling prevention material can be greatly increased.

[0007] The peeling prevention structure of the present invention is characterized in that another protruding step portion is formed around the end portion of the front panel opposite the folded portion of the comb-shaped clamping device, and another shape-retaining material of the shape-retaining body is accommodated in a pressed state in the another protruding step portion. According to this, by storing another shape-retaining material of the anti-peeling material in a pressed state in another protruding step portion around the end portion of the front plate of the comb-shaped clamp, the mounting state of the anti-peeling material can be made even more stable.

[0008] The anti-peeling structure of the present invention is characterized in that a clip back plate is provided by folding back from a clip front plate at a clip fold portion, a clip protruding step portion is formed adjacent to the clip fold portion of the clip front plate, and the clip front through hole of the clip front plate and the clip back through hole of the clip back plate are provided at corresponding positions from which the expanded anchor cannot escape, the clip-type holder is provided so as to clamp the vicinity of both end edges in the width direction of the anti-peeling material with the clip back plate on the mounting surface side, and each of the shape retaining materials of the shape retaining body provided at the end edges in the width direction is accommodated in a pressed state in the clip protruding step portion, the expansion anchor is driven into the concrete structure through the clip front through hole and the clip back through hole of the clip-type holder, and the anti-peeling material is attached by pressing the clip front plate of the clip-type holder against the mesh sheet side with a nut screwed onto the expansion anchor. According to this, the expansion anchor in the expanded state cast into the concrete structure cannot slip out of the clip-type retainer, and by providing the clip-type retainer so as to clamp it near the widthwise edge of the spalling prevention material, it is possible to prevent the expansion anchor in the expanded state from slipping out of the concrete structure and falling together with the clip-type retainer. Furthermore, for example, by holding down the edges of both sides of the widthwise direction of the spalling prevention material with the clip-type retainer and holding down the intermediate position between the both edges with the comb-type retainer, it is possible to further increase the stability of the installed state of the spalling prevention material, which is long in the width direction.

[0009] The spalling prevention structure of the present invention is characterized in that the expansion anchor is a core rod driving type anchor that expands deeper than the surface area where the concrete structure is expected to spall, and an adhesive is filled into the borehole into which the expansion anchor is driven. This makes it possible to more reliably prevent the expansion anchor from coming loose from the concrete structure, thereby further increasing the durability of the spalling prevention structure.

[0010] The comb-shaped clamp of the present invention is a spalling prevention structure in which a spalling prevention material having a lattice-shaped shape-retaining body superimposed on and fixed to a mesh sheet is laid so as to roughly follow the mounting surface of a concrete structure, and is a comb-shaped clamp used for mounting the spalling prevention material, characterized in that a plurality of comb teeth are provided at a folded-back portion from the front plate at a position where they do not overlap with the front through hole, and each of the comb teeth is formed so that it can be introduced into the mounting surface side through the mesh of the mesh sheet, a protruding step portion that accommodates the shape-retaining material that constitutes the shape-retaining body in a pressed state is formed adjacent to the folded-back portion of the front plate, and the diameter of the front through hole provided in the front plate, or the short diameter of the front through hole, is formed to be smaller than the outer diameter of the expansion anchor when expanded to be cast into the concrete structure. According to this, the expansion anchor in the expanded state cast into the concrete structure cannot slip out of the comb-shaped retainer, and by arranging each comb tooth of the comb-shaped retainer on the mounting surface side through the mesh of the mesh sheet, it is possible to prevent the expansion anchor in the expanded state from slipping out of the concrete structure and falling together with the comb-shaped retainer. In other words, it is possible to prevent the comb-shaped retainer that holds down the mesh sheet laid so as to substantially conform to the concrete structure and the expansion anchor to which the comb-shaped retainer is attached from falling off the concrete structure. In addition, each comb tooth of the comb-shaped retainer is arranged on the mounting surface side through the mesh of the mesh sheet, and it is possible to install it at any position where the shape retaining material can be accommodated in a pressed state in the protruding step portion, and the degree of freedom in the installation position of the retainer that holds the spalling prevention material can be greatly increased. Effect of the Invention

[0011] According to the present invention, it is possible to prevent the clamp that holds down the mesh sheet laid so as to follow roughly the concrete structure and the expansion anchor that attaches the clamp from falling off the concrete structure. [Brief description of the drawings]

[0012] [Figure 1] FIG. 2 is a perspective view of the inner surface of a tunnel lining on which a spalling prevention structure according to an embodiment of the present invention is installed. [Diagram 2] 13 is an enlarged perspective view of a portion where the anti-peeling material is attached by a clip-type holder in the anti-peeling structure of the embodiment. FIG. [Diagram 3] 4 is an enlarged cross-sectional view of a portion where the anti-peeling material is attached by a clip-type holder in the anti-peeling structure of the embodiment. FIG. [Figure 4] 13 is an enlarged perspective view of a portion where the anti-peeling material is attached by a comb-shaped pressing tool in the anti-peeling structure of the embodiment. FIG. [Diagram 5] 4 is an enlarged cross-sectional view of a portion where the anti-peeling material is attached by a comb-shaped holder in the anti-peeling structure of the embodiment. FIG. [Figure 6] (a) is a front view of the clip-type retainer, (b) is a cross-sectional view thereof, and (c) is a rear view thereof. [Figure 7] (a) is a front view of the comb-shaped clamp, (b) is a cross-sectional view thereof, and (c) is a rear view thereof. [Figure 8] FIG. [Figure 9] 1A is a front view of a core rod-driven anchor used in an embodiment of the anti-falling structure, FIG. 1B is an enlarged left side view thereof, FIG. 1C is an enlarged right side view thereof, and FIG. [Figure 10] 1(a) is an oblique explanatory diagram illustrating drilling into the mounting surface of a concrete structure on which anti-spare material has been laid, and 1(b) is an oblique explanatory diagram illustrating the casting of a core rod-driven anchor into the mounting surface of a concrete structure on which anti-spare material has been laid. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] [Peeling prevention structure of the embodiment] The anti-spare structure of an embodiment of the present invention is installed on deteriorated concrete of a concrete structure 100, such as the deteriorated lining concrete of a tunnel T, and as shown in Figures 1 to 5, comprises a planar anti-spare material 10 laid approximately along the mounting surface 101 of the concrete structure 100, a clip-type clamp 20 arranged to clamp both end edges of the anti-spare material 10 in the width direction, a comb-type clamp 30 arranged at the middle position of the anti-spare material 10 in the width direction, and a core rod driving-in anchor 40 equivalent to an expansion anchor that is inserted into the clip-type clamp 20 or the comb-type clamp 30 and cast into the concrete structure 100.

[0014] The planar anti-falling material 10 is composed of a net-like mesh sheet 11 and a lattice-like shape retaining body 12 that is overlaid and fixed on the mesh sheet 11, and the shape retaining body 12 is arranged and fixed at corresponding positions on both sides of the mesh sheet 11. The material and structure of the mesh sheet 11 and the shape retaining body 12 may be appropriate within an applicable range.

[0015] The peeling prevention material 10 is formed, for example, in a rectangular shape, and shape retaining materials 121 extending in the vertical direction of the shape retaining body 12 are provided along both end edges in the width direction, and shape retaining materials 122 extending in the vertical direction at a specified interval are provided inside the edge shape retaining materials 121. In the peeling prevention material 10 of this example, the edge shape retaining materials 121-121 are arranged and fixed at corresponding positions on both sides of the mesh sheet 11, and other shape retaining materials 122-122 are also arranged and fixed at corresponding positions on both sides of the mesh sheet 11.

[0016] The clip-type pressing tool 20 is made of a metal material such as stainless steel, and includes a clip front plate 21 having steps around both ends in the width direction and a flat clip back plate 22, as shown in Fig. 2, Fig. 3, and Fig. 6. The clip back plate 22 is provided so as to be folded back from the clip front plate 21 at a clip fold-back portion 23 that is curved in an arc shape in cross section so as to be elastically deformable. The clip front plate 21 has a clip protruding step portion 24 formed adjacent to the clip fold-back portion 23, and another clip protruding step portion 25 formed around the end of the clip front plate 21 on the opposite side to the clip fold-back portion 23, so that the clip front plate 21 is formed in a dish shape having edges in cross section. In other words, the clip protruding step portion 24 and another clip protruding step portion 25 are formed on both sides in the width direction of the flat clip base portion 211 of the clip front plate 21 so as to rise on the opposite side to the clip back plate 22. The clip protruding step portions 24, 25 are each formed over the entire length of the clip front plate 21 in the longitudinal direction, and the distance between the clip protruding step portion 24 and another clip protruding step portion 25 is set to a distance that approximately corresponds to the distance between the shape retaining material 121 at the edge of the lattice-shaped shape retaining body 12 and another shape retaining material 122 adjacent to it.

[0017] The clip front through hole 26 and the clip rear through hole 27 through which the core rod driving anchor 40 is inserted are provided at corresponding positions at approximately the center of the flat clip base 211 of the clip front plate 21 and the approximately the center of the clip rear plate 22. In the clip-type retainer 20 of this example, the clip front through hole 26 is formed as a round hole, and the diameter of the clip front through hole 26 is formed smaller than the outer diameter of the core rod driving anchor 40 when expanded, and the clip rear through hole 27 is formed as an elongated hole that is long in the width direction of the peeling prevention material 10, and the short diameter of the elongated clip rear through hole 27 is formed smaller than the outer diameter of the core rod driving anchor 40 when expanded. In other words, the clip front through hole 26 of the clip front plate 21 and the clip rear through hole 27 of the clip rear plate 22 are formed so that the core rod driving anchor 40 in the expanded state cannot slip out.

[0018] The comb-shaped presser 30 is made of a metal material such as stainless steel, and includes a front plate 31 having steps around both ends in the width direction, and a plurality of comb teeth 32, as shown in Figs. 4, 5, 7, and 8. The plurality of comb teeth 32 are provided by folding back the front plate 31 at a folded back portion 33 that is curved in an arc shape in cross section and elastically deformable. The front plate 31 has a protruding step portion 34 formed adjacent to the folded back portion 32, and another protruding step portion 35 formed around the end of the front plate 31 opposite the folded back portion 33, so that the front plate 31 is formed in a dish shape having edges in cross section. In other words, the protruding step portion 34 and another protruding step portion 35 are formed on both sides in the width direction of the flat base portion 311 of the front plate 31 so as to rise on the opposite side to the comb teeth 32. The protruding step portions 34, 35 are each formed over the entire length of the front panel 31 in the longitudinal direction, and the distance between the protruding step portion 34 and another protruding step portion 35 approximately corresponds to the distance between adjacent shape retaining materials 122-122 of the lattice-shaped shape retaining body 12.

[0019] A front through hole 36 through which the core rod driving anchor 40 is inserted is provided in the approximate center of the flat base 311 of the front plate 31, and the front through hole 36 is provided at a position that does not overlap with the multiple comb teeth 32. In the comb-shaped presser 30 of this example, the front through hole 36 is formed as an elongated hole that is long in the width direction of the anti-spare-off material 10, and the short diameter of the elongated front through hole 36 is formed smaller than the outer diameter of the core rod driving anchor 40 when expanded. In other words, the front through hole 36 of the front plate 31 is formed so that the core rod driving anchor 40 in the expanded state cannot slip out. When the front through hole 36 is formed as a round hole, it is preferable to form the diameter of the round hole front through hole 36 smaller than the outer diameter of the core rod driving anchor 40 when expanded.

[0020] Each of the multiple comb leaves 32 is formed to a size that allows it to pass through the mesh 111 of the mesh sheet 11 of the anti-peeling material 10, and is positioned so that it can be inserted therethrough. When the front plate 31 is positioned on the opposite side of the mounting surface 101 relative to the mesh sheet 11, each comb tooth 32 is formed so that it can be introduced through the mesh 111 of the mesh sheet 11 to the mounting surface 101 side.

[0021] As shown in Fig. 9, a core rod driving-in anchor 40, which corresponds to an expansion anchor, is composed of a sleeve-shaped anchor body 41 and a core rod 42 inserted into the anchor body 41. The anchor body 41 in this example is formed in a substantially cylindrical shape, with multiple slits 43 cut in the axial direction from the tip, and an expansion piece 44 is provided so as to be divided by the multiple slits 43 spaced apart in the circumferential direction. A step portion 45 is formed on the inside of the expansion piece 44, and when the core rod 42 is driven in the tip direction, the warhead-shaped tip portion 421 enters the step portion 45, causing the expansion piece 44 to expand.

[0022] A male thread 47 is formed on the outer peripheral surface of the rear end 46 of the anchor body 41, and a nut 51 such as a locking nut is screwed onto the male thread 47 when the core rod driving anchor 40 is driven into the concrete structure 100 (see Figs. 1 to 5). A spiral groove 48 is formed on the entire outer periphery of the anchor body 41 in front of the rear end 46, which serves as a flow path for the adhesive 60. The spiral groove 48 is preferably formed on the outer periphery of the anchor body 11 by rolling, but it can also be formed by other processing methods such as cutting. The outer diameter of the spiral part of the anchor body 41 where the spiral groove 48 is formed is, for example, 8.2 mm, and the length of the spiral part corresponding to the embedding length is, for example, 15 times or more the outer diameter of the spiral part. In addition, a sawtooth part 422 is formed by serration processing near the rear end of the core rod 42, and the driven core rod 42 is prevented from slipping out of the anchor body 41 by frictional contact with the sawtooth part 422.

[0023] In the spalling prevention structure of this embodiment, the spalling prevention material 10 is laid so as to substantially follow the mounting surface 101 of the concrete structure 100. Then, holes 102 are formed with a drill 71 at predetermined positions on the mounting surface 101 of the concrete structure 100 so as to penetrate the mesh sheet 11 near both edges of the spalling prevention material 10, and the clip-type retainer 20 is provided so as to sandwich the vicinity of both end edges in the width direction of the spalling prevention material 10 in a substantially U-shaped manner, with the clip back plate 22 facing the mounting surface 101 (see Figs. 2, 3, and 10(a)).

[0024] The clip-type presser 20 is positioned so that the clip front through-hole 26 and the clip back through-hole 27 are positioned to correspond to the perforations 102, and is positioned so that the shape retainers 121-121 at the widthwise edge of the anti-peeling material 10 are accommodated in the clip protruding step portion 24 of the clip-type presser 20, and the clip protruding step portion 25 of the clip-type presser 20 accommodates other shape retainers 122-122 near the inside of the anti-peeling material 10. Furthermore, a plurality of clip-type pressers 20 are provided on each edge of the anti-peeling material 10 at predetermined intervals in the length direction.

[0025] Then, either before or after installing the clip-type presser 20, the inside of the perforation 102 is cleaned, and adhesive 60 is injected into the perforation 102 (see FIG. 3). Any suitable adhesive may be used for the adhesive 60 within the scope of the present invention, and it is preferable to use, for example, a two-liquid mixed type resin adhesive in which a thixotropic semi-liquid epoxy resin base agent and a semi-liquid polyamine hardener are mixed.

[0026] Thereafter, the core rod driving-in anchor 40 is inserted into the perforation 102 in which the uncured adhesive 60 exists, so as to communicate with the clip front through-hole 26 and the clip rear through-hole 27 of the clip-type retainer 20, and is positioned so that the rear end 46 of the anchor body 41 is exposed from the perforation 102 (see Figs. 3 and 10(b)). At this time, as the core rod driving-in anchor 40 is inserted, the uncured adhesive 60 in the perforation 102 flows along the spiral groove 48.

[0027] Furthermore, the core rod 42 is driven in with a hammer 72 to expand the expansion piece 44, and the core rod driving type anchor 40 is cast into the concrete structure 100 so that the expanded piece 44 bites into the wall of the borehole 102 (see Fig. 3 and Fig. 10(b)). By casting the core rod driving type anchor 40 that penetrates the spalling prevention material 10 in an expanded state, the clip-type retainer 20 and the spalling prevention material 10 are temporarily fixed to the mounting surface 101. The core rod driving type anchor 40, which corresponds to an expansion anchor, is cast so that it expands behind the surface layer part where spalling of the concrete structure 100 is expected.

[0028] Then, as shown in Figures 2 and 3, a washer 52 is inserted onto the male thread 47 of the core rod driving anchor 40, and a nut 51, which is an anti-loosening nut, is screwed onto the male thread 47 and tightened. The nut 51 presses the clip-type retainer 20 toward the mounting surface 101, and the pressed clip-type retainer 20 presses the shape-retaining body 12 toward the mounting surface 101, thereby attaching the anti-spare material 10 to the concrete structure 100. In other words, the edge shape-retaining materials 121-121 are sandwiched between the clip protruding step portion 24 of the clip-type retainer 20 and the clip back plate 22 and accommodated in a pressed state, and another shape-retaining material 122-122 is sandwiched between the clip protruding step portion 25 of the clip-type retainer 20 and the clip back plate 22 and accommodated in a pressed state, and the clip front plate 21 of the clip-type retainer 20 is pressed against the mesh sheet 11 by tightening the nut 51, thereby attaching the anti-spare material 10 to the concrete structure 100.

[0029] Also, a drill 71 is used to form a hole 102 at a predetermined position on the mounting surface 101 of the concrete structure 100 at a midpoint between both edges of the peeling prevention material 10 so as to penetrate the mesh sheet 11 of the peeling prevention material 10 laid so as to substantially follow the mounting surface 101 of the concrete structure 100, and a comb-shaped retainer 30 is provided at the midpoint between both edges of the peeling prevention material 10. The comb-shaped retainer 30 is arranged with its front plate 31 on the opposite side of the mesh sheet 11 to the mounting surface 101, and each of its comb teeth 32 is introduced through the mesh 111 of the mesh sheet 11 to the mounting surface 101 side. Furthermore, the comb-shaped presser 30 is arranged so that the shape retaining materials 122 extending in the vertical direction of the anti-peeling material 10 are accommodated in the protruding step portion 34, and another shape retaining material 122 extending in the vertical direction is arranged to be accommodated in the protruding step portion 35 (see Figures 4, 5, 8 and 10(a)). Furthermore, a plurality of comb-shaped pressers 30 are provided on each edge of the anti-peeling material 10 at predetermined intervals in the longitudinal direction.

[0030] Before or after installing the comb-shaped retainer 30, the inside of the perforation 102 is cleaned and an adhesive 60 is injected into the perforation 102 (see FIG. 5). The adhesive 60 can be the same as that used for the clip retainer 20, and it is preferable to use, for example, a two-liquid mixed type resin adhesive in which a thixotropic semi-liquid epoxy resin base agent and a semi-liquid polyamine hardener are mixed.

[0031] Thereafter, the core rod driving-in anchor 40 is inserted into the borehole 102, in which the uncured adhesive 60 exists, so as to pass through the front through-hole 36 of the comb-shaped presser 30 and between the comb teeth 32-32, and is positioned so that the rear end 46 of the anchor body 41 is exposed from the borehole 102 (see Figures 5 and 10(b)). At this time, as the core rod driving-in anchor 40 is inserted, the uncured adhesive 60 in the borehole 102 flows along the spiral groove 48.

[0032] Furthermore, the core rod 42 is driven in with a hammer 72 to expand the expansion piece 44, and the core rod driving type anchor 40 is cast into the concrete structure 100 so that the expanded expansion piece 44 bites into the wall of the borehole 102 (see Fig. 5 and Fig. 10(b)). By casting the core rod driving type anchor 40 that penetrates the spalling prevention material 10 in an expanded state, the comb-shaped retainer 30 and the spalling prevention material 10 are temporarily fixed to the mounting surface 101. The core rod driving type anchor 40, which corresponds to an expansion anchor, is cast so that it expands behind the surface layer part where spalling of the concrete structure 100 is expected.

[0033] 4 and 5, a washer 52 is inserted onto the male thread 47 of the core rod driving anchor 40, a nut 51 which is an anti-loosening nut is screwed onto the male thread 47 and tightened, the nut 51 presses the comb-shaped holder 30 towards the mounting surface 101, and the pressed comb-shaped holder 30 presses the shape retainer 12 towards the mounting surface 101, thereby attaching the spalling prevention material 10 to the concrete structure 100. In other words, the shape retainers 122·122 are housed in a pressed state in the protruding step portion 34 of the comb-shaped holder 30, and another shape retainer 122·122 located adjacent to the shape retainer 122·122 is housed in a pressed state in the protruding step portion 35 of the comb-shaped holder 30, and the front plate 31 of the comb-shaped holder 30 is pressed against the mesh sheet 11 by tightening the nut 51, thereby attaching the spalling prevention material 10 to the concrete structure 100.

[0034] According to the spalling prevention structure of this embodiment, the core rod driving anchor 40, which corresponds to the expansion anchor in an expanded state cast into the concrete structure 100, cannot slip out of the comb-shaped retainer 30, and by arranging each comb tooth 32 of the comb-shaped retainer 30 on the mounting surface 101 side through the mesh 111 of the mesh sheet 11, it is possible to prevent the expansion anchor in an expanded state from slipping out of the concrete structure 100 and falling together with the comb-shaped retainer 30. In other words, it is possible to prevent the comb-shaped retainer 30, which holds down the mesh sheet 11 laid so as to substantially follow the concrete structure 100, and the expansion anchor to which the comb-shaped retainer 30 is attached, from falling out of the concrete structure 100. Furthermore, the comb-shaped clamp 30 can be installed in any position where each of the comb teeth 32 can be placed on the mounting surface 101 side through the mesh 111 of the mesh sheet 11 and the shape-retaining material 122, etc. can be accommodated in a pressed state in the protruding step portions 34, 35, greatly increasing the freedom in the mounting position of the clamp that holds the anti-peeling material 10.

[0035] In addition, by accommodating the shape-retaining material 122 of the anti-peeling material 10 in the protruding step portion 34 around the end portion of the front panel 31 of the comb-shaped clamp 30, and accommodating another shape-retaining material 122 of the anti-peeling material 10 in a pressed state in another protruding step portion 35, the installation state of the anti-peeling material 10 can be made even more stable.

[0036] Furthermore, the core rod driving anchor 40, which corresponds to the expansion anchor in an expanded state cast into the concrete structure 100, cannot slip out of the clip-type retainer 20, and by providing the clip-type retainer 20 so as to clamp it near the widthwise edge of the anti-spare material 10, it is possible to prevent the expansion anchor in an expanded state from slipping out of the concrete structure 100 and falling together with the clip-type retainer 20. Furthermore, by holding down the edges of both sides of the anti-spare material 10 in the widthwise direction with the clip-type retainer 20 and holding down the intermediate position between the both edges with the comb-type retainer 30, it is possible to further increase the stability of the installed state of the anti-spare material 10, which is long in the width direction.

[0037] In addition, by casting the core rod driving-in anchor 40 that expands deeper than the surface area where spalling of the concrete structure 100 is expected, and filling the borehole 102 into which the core rod driving-in anchor 40 is cast with adhesive 60, it is possible to more reliably prevent the core rod driving-in anchor 40, which is equivalent to the expansion anchor, from coming loose from the concrete structure 100, and further increase the durability of the spalling prevention structure.

[0038] [Scope of the invention disclosed herein] The inventions disclosed in this specification include, in addition to the inventions and embodiments listed as inventions, those specified by changing partial contents of these to other contents disclosed in this specification, those specified by adding other contents disclosed in this specification to these contents, or those specified by deleting partial contents of these to the extent that partial effects can be obtained, and specifying them as a higher-level concept. The inventions disclosed in this specification also include the following contents and modifications.

[0039] For example, in the above embodiment of the anti-peeling structure, a core rod driving type anchor 40 is used as a suitable example of an expansion anchor, but the expansion anchor used in the anti-peeling structure of the present invention is not limited to this and may be any appropriate anchor within the spirit and scope of the present invention.

[0040] In addition, in the above embodiment of the anti-peeling structure, the shape-retaining body 12 in the planar anti-peeling material 10 is configured to be fixed to both sides of the mesh sheet 11, but it is also possible to construct the anti-peeling structure of the present invention using an anti-peeling material in which the shape-retaining body is fixed to only one side of the mesh sheet.

[0041] In addition, the spalling prevention structure of the present invention is preferably constructed by laying the spalling prevention material so as to cover the lining concrete joints of tunnel T, which tend to become brittle, but it is also possible to construct it by laying the spalling prevention material in any suitable area of ​​the concrete structure, such as an area other than the lining concrete joints, and it is also possible to install it in concrete structures other than tunnels.

[0042] In addition, the anti-peeling structure of the present invention can also be constructed using only the comb-shaped holder 30 without using the clip-type holder 20, for example by providing comb-shaped holders 30 at positions near both end edges of the anti-peeling material 10. [Industrial Applicability]

[0043] The present invention can be installed and used in various concrete structures such as tunnels, bridges, towers, etc. where there is a risk of falling debris, or in parts of various concrete structures such as pillars, beams, girders, walls, and the undersides of slabs where there is a risk of falling debris. [Explanation of symbols]

[0044] 10... Anti-peeling material 11... Mesh sheet 111... Mesh 12... Shape retaining body 121, 122... Shape retaining material 20... Clip-type retainer 21... Clip front plate 211... Clip base 22... Clip rear plate 23... Clip folded-back portion 24, 25... Clip overhang step portion 26... Clip front through hole 27... Clip rear through hole 30... Comb-type retainer 31... Front plate 311... Base 32... Comb teeth 33... Folded-back portion 34, 35... Overhang step portion 36... Front through hole 40... Core rod driving anchor 41... Anchor body 42... Core rod 421... Tip portion 422... Sawtooth portion 43... Slit 44... Expansion piece 45... Step portion 46... Rear end portion 47... Male thread 48... Spiral groove 51... Nut 52... Washer 60... adhesive 71... drill 72... hammer 100... concrete structure 101... mounting surface 102... drilling T... tunnel

Claims

1. A peeling prevention material in which a lattice-shaped shape retaining body is layered and fixed on a mesh sheet; a comb-shaped retainer having a front plate having a front through hole through which the expanded anchor cannot slip out, a plurality of comb teeth provided at a folded portion at a position not overlapping the front through hole, and a protruding step portion formed adjacent to the folded portion of the front plate; The spalling prevention material is laid so as to substantially follow the mounting surface of the concrete structure, The comb teeth of each of the comb-shaped pressers are disposed on the mounting surface side through the mesh of the mesh sheet, The shape-retaining material constituting the shape-retaining body is accommodated in a pressed state in the protruding step portion of the comb-shaped pressing tool, The expansion anchor is driven into the concrete structure through the front through hole of the comb-shaped retainer, A peeling prevention structure characterized in that the peeling prevention material is attached by pressing the front plate of the comb-shaped retainer against the mesh sheet with a nut screwed onto the expansion anchor.

2. Another protruding step portion is formed around the end portion of the front plate opposite the folded portion of the comb-shaped presser, 2. The structure for preventing peeling off according to claim 1, wherein another shape retaining material of the shape retaining body is accommodated in the other protruding step portion in a pressed state.

3. a clip-type retainer in which a clip rear plate is provided by folding back a clip front plate at a clip fold-back portion, a clip protruding step portion is formed adjacent to the clip fold-back portion of the clip front plate, and a clip front through hole of the clip front plate and a clip rear through hole of the clip rear plate are provided at corresponding positions so that the expansion anchor in the expanded state cannot slip out, The clip-type retainer is provided so as to sandwich the vicinity of both end edges in the width direction of the anti-peeling material with the clip back plate on the mounting surface side, and each of the shape retaining materials of the shape retaining body provided on the end edges in the width direction is accommodated in a pressed state in the clip protruding step portion, The expansion anchor is driven into the concrete structure through the clip front through hole and the clip rear through hole of the clip-type retainer, The anti-peeling structure according to claim 1, characterized in that the anti-peeling material is attached by pressing the clip front plate of the clip-type retainer against the mesh sheet with a nut screwed onto the expansion anchor.

4. As the expansion anchor, a core rod driving type anchor is driven in which the concrete structure is expanded on the back side of the surface layer portion where spalling is expected, A peeling prevention structure as described in any one of claims 1 to 3, characterized in that an adhesive is filled into the borehole into which the expansion anchor is driven.

5. A spalling prevention structure in which a spalling prevention material having a lattice-shaped shape retainer overlapped and fixed to a mesh sheet is laid so as to substantially follow the mounting surface of a concrete structure, the spalling prevention material being attached to a concrete structure by a comb-shaped retainer, A plurality of comb teeth are provided at a folded portion folded back from the front plate at a position not overlapping with the front through hole, Each of the comb teeth is formed so as to be able to be introduced to the mounting surface side through the mesh of the mesh sheet, A protruding step portion for accommodating the shape retaining material constituting the shape retaining body in a pressed state is formed adjacent to the folded portion of the front plate, A comb-shaped clamp characterized in that the diameter or minor axis of the front through hole provided in the front plate is formed smaller than the outer diameter of the expansion anchor when it is installed in the concrete structure.

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