mold

Abstract

To provide a mold, which covers an inner wall of a manhole from inside of the inner wall so as to leave a filling space between the inner wall and the mold and has improved strength.SOLUTION: A mold 1 covers an inner wall of a manhole from inside of the inner wall so as to leave a filling space between the inner wall and the mold. A part (from vicinity of a fork part 20 through a connection part 23 to a tip edge of a lap part 22 on a flat plate part 10) or the whole is formed by stacking a woven fabric GC of glass fibers and a nonwoven fabric GM of glass fibers and hardening them with resin.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a mold that covers the inner wall of a manhole from the inside while leaving a filling space between the mold and the inner wall.

Background Art

[0002] Manholes are generally made of concrete and the inner wall surface may be corroded by hydrogen sulfide generated in underground pipes, especially sewer pipes, over a long period of time. Also, in manholes buried in roadways, cracks may occur on the inner wall surface due to vehicle vibrations. Furthermore, the strength of the manhole may decrease due to aging deterioration. In these cases, repair of the manhole is necessary.

[0003] However, due to traffic conditions and in order to reduce repair costs, it is difficult to repair manholes by excavation.

[0004] Therefore, as a method of repairing a manhole using a non-excavation repair material (hereinafter referred to as a mold), an arc-shaped mold is inserted into the manhole from the opening of the manhole entrance in a reduced diameter state, the mold is expanded, and one end portion and the other end portion in the circumferential direction of the mold are joined together to form a cylindrical shape. A filling material is filled between the outer peripheral surface of the cylindrical mold and the inner peripheral wall of the manhole, and the filling material is cured so that the inner peripheral surface of the mold becomes a new inner peripheral wall of the manhole (see, for example, Patent Document 1, etc.).

[0005] Also, there are cases where a plurality of divided molds are joined together and the inner surface of the joined molds becomes a new inner wall of the manhole.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] In the mold with the new inner wall, in addition to the corrosion by hydrogen sulfide, the influence of vehicle vibration, and aging deterioration described above, external forces are applied due to earth pressure, earthquakes, etc., and tensile forces and compressive forces are generated. For this reason, the mold is required to have higher strength.

[0008] In view of the above circumstances, an object of the present invention is to provide a mold with higher strength.

Means for Solving the Problem

[0009] The mold of the present invention for solving the above object is a mold that covers the inner wall of the manhole from the inside of the inner wall leaving a filling space between it and the inner wall, characterized in that part or all of it is formed by laminating a woven fabric of glass fiber and a non-woven fabric of glass fiber and solidifying them with resin.

[0010] The woven fabric of glass fiber has higher strength than the non-woven fabric of glass fiber. For this reason, according to the mold of the present invention, since the woven fabric of glass fiber is included, the strength is higher.

[0011] Note that the inner wall may be a peripheral wall or a ceiling wall.

[0012] Also, the resin is preferably a resin resistant to hydrogen sulfide.

[0013] Since the mold itself may be corroded by hydrogen sulfide, it is preferable to use a resin resistant to hydrogen sulfide. For example, the resin is preferably a vinyl ester resin.

[0014] Also, it may be characterized in that part or all of it sandwiches the woven fabric of glass fiber with the non-woven fabric of glass fiber.

[0015] The strength of one side surface becomes the same as that of the other side surface, and the woven fabric of the glass fiber functions like a core material.

[0016] Also, a base portion, a first end portion closer to the inner wall side than the base portion, and a connecting portion connecting the base portion and the first end portion, the first end portion overlaps with a second end portion located on the side opposite to the inner wall side, and at least each of the boundary between the base portion and the connecting portion and the boundary between the first end portion and the connecting portion has a portion where the woven fabric of the glass fiber and the non-woven fabric of the glass fiber are overlapped and solidified with resin.

[0017] Note that at least from the portion of the base portion on the connecting portion side to the portion of the first end portion on the connecting portion side, the woven fabric of the glass fiber and the non-woven fabric of the glass fiber may be overlapped and solidified with resin.

[0018] Also, the first end portion and the second end portion may be the end portions on one side and the other side of a common mold. That is, both end portions in the circumferential direction of a single arc-shaped mold are connected, the first end portion is the end portion on one side in the circumferential direction of the arc-shaped mold, and the second end portion may be the end portion on the other side in the circumferential direction of the arc-shaped mold.

[0019] Alternatively, the first end portion and the second end portion may be the end portions of different molds. That is, a mold connection body having a first mold and a second mold, the first mold and the second mold are connected, the first end portion is the end portion of the first mold on the second mold side, and the second end portion may be the end portion of the second mold on the first mold side.

Advantages of the Invention

[0020] According to the present invention, a mold with enhanced strength can be provided.

Brief Description of the Drawings

[0021]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0022] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0023] FIG. 1 is a diagram showing an example of a manhole to be repaired.

[0024] A manhole is an entrance for a person to inspect an underground structure where people cannot normally enter and exit, and it is a buried concrete molded body. Some manholes are made by placing concrete on site, and some have a structure in which assembled types manufactured in a factory are stacked. FIG. 1 shows an example of the latter. Also, the manhole shown in FIG. 1 is for a sewer.

[0025] Fig. 1(A) is a perspective view schematically showing a manhole, and Fig. 1(B) shows a cross-sectional view seen from the side of the manhole. In Fig. 1(A), the left front side of the figure is the front side, and the right rear side is the back side. Also, in Fig. 1(B), the left side of the figure is the front side, and the right side is the back side.

[0026] As shown in Fig. 1(A), the opening of the inlet Mi of the manhole M of this embodiment is circular, and the inclined wall portion M2 installed via the height adjustment member M1 below the inlet Mi and the straight wall portion M3 connected to the lower part of the inclined wall portion M2 also have a circular horizontal cross-section. On the other hand, the rectangular portion M4 connected to the lower part of the straight wall portion M3 has a rectangular horizontal cross-section.

[0027] The inner diameter IL of the inlet of the manhole M is 600 mm, while the lateral inner dimension XL of the rectangular portion M4 is 2000 mm, and the longitudinal inner dimension YL is also 2000 mm. The inner diameter is enlarged by the inclined wall portion M2, and the inner diameter DL of the straight wall portion M3 is 900 mm. Also, in this Fig. 1(A), the flat mold 1 that covers the inner wall of the rectangular portion M4 from the inside of the inner wall leaving a filling space between it and the inner wall is represented by a two-dot chain line. On the vertical walls (front wall M4F, right side wall M4R, etc.) of the rectangular portion M4, a flat mold 1 with a width of 650 mm and a mold piece 2 for width adjustment are shown. Also, on the ceiling wall (top plate Mt) of the rectangular portion M4, a flat mold 6 with a width of 350 mm and a mold piece 7 for width adjustment are shown. The installation of each flat mold and the like will be described later.

[0028] Fig. 1(B) shows an openable and closable lid MC that closes the opening of the inlet of the manhole M, a receiving frame MR that receives the lid MC, a height adjustment member M1, an inclined wall portion M2, and a straight wall portion M3. Also, the rectangular portion M4 connected to the lower part of the straight wall portion M3 is shown. On the inclined wall portion M2, the straight wall portion M3, and the rectangular portion M4, lifting brackets SP are attached to the inner peripheral wall on the back side.

[0029] The height adjustment member M1 is a member for adjusting the surface of the lid MC to the height position of the ground, and can be a mortar for adjustment, a ready-made adjustment ring, or a concrete ring cast on the construction site. A receiving frame MR is installed on the height adjustment member M1.

[0030] The inclined wall portion M2 is made of concrete manufactured in a factory. As shown in Fig. 1(B), this inclined wall portion M2 is inclined radially outward downward over the entire circumference.

[0031] The straight wall portion M3 is also made of concrete manufactured in a factory. This straight wall portion M3 is cylindrical, and here, straight wall bodies M30 with different heights are stacked in two layers. Note that there are straight wall bodies M30 with various heights.

[0032] The rectangular portion M4 is composed of a top plate Mt, a side wall body Ms, and a pipe mounting wall body Ma.

[0033] The top plate Mt is a horizontal plate made of concrete manufactured in a factory. This top plate Mt forms the ceiling of the rectangular portion M4.

[0034] The side wall body Ms is also made of concrete manufactured in a factory. This side wall body Ms is rectangular, and here it is composed of one layer. Note that there are side wall bodies Ms with various heights, and there may be cases where they are stacked in multiple layers.

[0035] The pipe mounting wall body Ma is also a rectangular one made of concrete manufactured in a factory. As shown in Fig. 1(B), an inflow pipe IP and an outflow pipe OP are respectively connected to the pipe mounting wall body Ma. The arrows in the figure indicate the direction in which the sewage flows. Both the inflow pipe IP and the outflow pipe OP have a large diameter. For example, the diameter exceeds 700 mm to 1000 mm. For such large-diameter inflow pipes IP and outflow pipes OP, it is difficult to use a cylindrical manhole, and a rectangular manhole is used.

[0036] An invert IN is arranged at the bottom of the pipe attachment wall Ma, and the inflow pipe IP and the outflow pipe OP are connected by a groove INg provided in this invert IN.

[0037] FIG. 2 is a diagram showing a flowchart of the manhole lining construction method shown in FIG. 1.

[0038] First, ground treatment is performed (step S1). In the ground treatment, dirt, sediment deposits, weak parts, and deteriorated parts on the inner peripheral wall of the manhole M are removed by high-pressure cleaning. If there are still deteriorated parts after high-pressure cleaning, the deteriorated parts are scraped off by scraping work.

[0039] In step S2, pre-construction treatment is performed. In this pre-construction treatment, the foothold fitting SP is cut and removed. Also, when there are large cracks on the inner peripheral surface of the manhole M or when infiltrating water leaks out, a filler is filled and sealing treatment is performed.

[0040] In step S3, a construction surface survey is performed. In the manhole lining construction method of the present embodiment, it is preferable to perform the construction after returning the manhole M to its original inner dimensions. For this reason, a construction surface survey is performed, and the inner peripheral surface of the manhole M may be repaired using a repair material. The repaired inner peripheral surface is preferably processed into an uneven shape in order to improve the adhesiveness with the filler described later.

[0041] Subsequently, a flat mold is installed in the rectangular portion M4. The flat mold is installed over the entire inner wall of the rectangular portion M4 inside the inner wall of the rectangular portion M4, and is for forming a filling space for filling a filler between the outer surface of the flat mold and the inner wall of the rectangular portion M4.

[0042] In step S4, the flat mold 1 is inserted through the opening of the manhole inlet Mi.

[0043] FIG. 3 is a diagram showing the flat mold.

[0044] The flat mold 1 shown in Fig. 3(A) is a repair material made of a resin mainly composed of a vinyl ester resistant to hydrogen sulfide. In manholes with a high concentration of hydrogen sulfide, cases have been reported where the mold itself and the joints of the molds are corroded by hydrogen sulfide, and hydrogen sulfide penetrates into the filler filled and cured in the filling space, causing corrosion of the filler as well. Therefore, in this embodiment, the mold itself is also resistant to hydrogen sulfide. As another resin resistant to hydrogen sulfide, polyethylene can be mentioned.

[0045] The lateral width WL of the flat mold 1 is 650 mm. Although the lateral width WL of the flat mold 1 is longer than the inner diameter IL of the inlet Mi of the manhole M shown in Fig. 1(A), in step S4, the flat mold 1 can be inserted into the rectangular portion M4 from the inlet Mi by bending it in the lateral width direction.

[0046] The height of the flat mold 1 shown in Fig. 3(A) is 1500 mm, but for example, those with various heights can be prepared in the range of 3000 mm or less. In the flat mold 1 shown in Fig. 3(A), the side closer to the paper surface is the side of the rectangular portion M4 (the side where the filling space is formed). In the following description, the surface of the flat mold 1 that becomes the side of the rectangular portion M4 (the side where the filling space is formed) may be referred to as the outer surface OS, and the opposite surface may be referred to as the inner surface IS.

[0047] The flat mold 1 has a flat plate portion 10 with a lateral width of 600 mm and a bifurcated portion 20 with a lateral width WL2 of more than 50 mm.

[0048] The thickness of the flat part 10 is about 2 mm. On the outer surface OS of the flat part 10, four protruding ribs 11 protruding toward the rectangular part M4 side (the side where the filling space is formed) are provided in upper and lower two stages. The protruding length of the rib 11 is the designed thickness (for example, 6 mm). These ribs 11 come into contact with the inner wall of the rectangular part M4, and a filling space with the above-mentioned designed thickness is formed between the outer surface OS of the flat mold 1 and the inner wall of the rectangular part M4. Each rib 11 has a shorter length in the width direction than in the vertical direction so as not to prevent the filling material from flowing down. That is, the rib 11 is a square bar made of a resin mainly composed of a vinyl ester resistant to hydrogen sulfide, with a vertical length of 300 mm and a width of about 15 mm. When manufacturing the flat mold 1 in the factory, each rib 11 is attached to the outer surface OS of the flat part 10 with an adhesive while ensuring a horizontal interval and a vertical interval of about 200 mm each.

[0049] An injection hole 12 for injecting the filling material is drilled on-site at the upper end of the flat part 10, and anchor holes 13 for driving anchors at intervals of 250 mm or more and 500 mm or less in the height direction are drilled on-site at the central part in the width direction of the flat part 10. These holes 12 and 13 are shown by a one-dot chain line in Fig. 3(A).

[0050] The bifurcated part 20 has a covering part 21 extending directly from the flat part 10, which is provided over the entire height at one end side in the horizontal direction, a wrap part 22 extending in the width direction while maintaining a parallel relationship with the covering part 21 at a position about 4 mm closer to the manhole M side from the flat part 10, and a connecting part 23 connecting the flat part 10 and the wrap part 22. The width of the wrap part 22 is 50 mm. A screw hole 222 is drilled on-site at a position where the wrap part 22 does not overlap with the covering part 21. In Fig. 3(A), this screw hole 222 is also shown by a one-dot chain line. Incidentally, the screw hole 222 may also be drilled in the flat part 10. The screw hole 222 is a through hole smaller than the anchor hole 13.

[0051] Fig. 3(B) is a schematic cross-sectional view of the wrap part 22 in the flat mold 1 shown in Fig. 3(A), with the upper part of the figure being the outer surface OS side.

[0052] The thickness of the wrap portion 22 is also about 2 mm. The wrap portion 22 is formed by sandwiching a sheet GC of a glass roving cloth (woven fabric) woven with horizontal threads of flat glass fibers similar to the vertical threads of flat glass fibers between a sheet GM of a chopped strand mat (non-woven fabric) in which short glass fibers are dispersed, and solidifying these three sheets with a resin mainly composed of vinyl ester resistant to hydrogen sulfide. The sheet GC of the glass roving cloth has higher strength than the sheet GM of the chopped strand mat but is expensive. By inserting the sheet GC of the glass roving cloth in between, the strength and durability of the wrap portion 22 are increased. Also, the difference in strength between one side surface and the other side surface disappears, and the sheet GC of the glass roving cloth functions like a core material. The flat mold 1 has a structure in which a plurality of long strip-shaped sheets in the vertical direction are arranged side by side in the lateral width direction and solidified with a resin mainly composed of vinyl ester to form an integral body. Since the sheet GC of the glass roving cloth is expensive, in most parts of the flat portion 10 and the covering portion 21, the sheet GC of the glass roving cloth is not used, and instead, three sheets of the sheet GM of the chopped strand mat are stacked and solidified with a resin mainly composed of vinyl ester. However, in the lining portions where high strength is required or the lining portions where cost can be spent, even in the entire flat portion 10 or the covering portion 21, a structure in which the sheet GC of the glass roving cloth is sandwiched between the sheet GM of the chopped strand mat may be adopted. For example, a structure in which the sheet GC of the glass roving cloth is sandwiched between the sheet GM of the chopped strand mat may be adopted over the entire flat mold 1. Also, in the case of a three-layer structure, the position of the sheet GC of the glass roving cloth is not limited to the middle position, and may be a position on the outer surface OS side or a position on the inner surface IS side. Further, a three-layer structure may be formed with the sheet GC of the glass roving cloth, or a three-layer structure in which the sheet GM of the chopped strand mat is sandwiched between the sheet GC of the glass roving cloth may be formed. Alternatively, not limited to the three-layer structure, a two-layer structure or a structure of four or more layers including the sheet GC of the glass roving cloth may be formed. That is, any structure having the sheet GC of the glass roving cloth is acceptable.

[0053] Also, when manufacturing the flat mold 1 in the factory, a primer layer PM is provided at locations in contact with the resin, such as the outer surface OS and the inner surface of the wrap portion 22. In Fig. 3(B), the primer layer PM is indicated by a cross mark. As the primer layer PM, for example, a layer coated with a polyester-based primer can be mentioned. The primer layer PM has a function of improving the adhesiveness with the resin and also a function of improving the adhesiveness with the joint material. Therefore, the joint material is less likely to flow down due to the primer layer PM. Furthermore, since the primer layer PM improves the smoothness of the base and also improves the durability of the resin of the joint material, the primer layer PM also has a function as a surfacer layer and can be regarded as a primer surfacer (prasurf) layer.

[0054] Furthermore, in manufacturing the flat mold 1 at the factory, a resin support structure is provided on the inner surface (the surface on the covering portion 21 side) of the wrap portion 22. As will be described later, the end of the flat plate portion 10 of another flat mold 1 is inserted between the bifurcated portions 20 (between the wrap portion 22 and the covering portion 21), and the end of another flat mold 1 overlaps the wrap portion 22. The lap portion where the flat molds 1 overlap each other is subjected to joint treatment. In joint treatment, joint materials such as silicone putty and acid-resistant epoxy putty are often used, but in this embodiment, a resin resistant to hydrogen sulfide is used as the joint material. For example, a resin mainly composed of vinyl ester, which is the same resin used for the flat mold 1, is used. By using, as the joint material, a material mainly composed of the same resin used for the flat mold 1 in this way, the adhesive strength can be increased. The resin mainly composed of vinyl ester has a low viscosity and is likely to drip. Therefore, it is necessary to devise a way to keep the resin in the lap portion until the resin hardens. The resin support structure of this embodiment is such that a resin support sheet 30 provided with a communication space communicating in the thickness direction is attached with a double-sided tape 31. The communication space mentioned here is a space connecting from one surface 30a of the resin support sheet 30 to the other surface 30b, and it may have a shape that is not limited to a straight line but is intricate. One surface 30a is the surface to which the resin support sheet 30 is attached with the double-sided tape 31 and is the surface located on the wrap portion 22 side. Examples of the resin support sheet 30 include a 1-mm-thick felt or a foam sheet. A mesh-like sheet may also be used. The inner surface of the wrap portion 22 is preferably covered as much as possible by this resin support sheet 30. That is, the resin support sheet 30 is preferably provided over the entire length in the height direction of the wrap portion 22 and also provided over as wide a range as possible in the lateral width direction. The resin supplied in the joint treatment enters the communication space, is held for a certain period of time, gradually oozes out from each of the surfaces 30a and 30b on both sides of the sheet, and eventually hardens. Since the double-sided tape 31 may prevent the resin from oozing out, it is preferably as thin and short as possible.

[0055] As for the resin support structure, the inner surface of the wrap portion 22 may be formed into a structure with recesses provided by shot peening (a matte finish structure), or may be formed into a structure with serrated grooves provided by machining. Alternatively, serrated grooves may be formed when hardening with resin during the production of the flat mold 1.

[0056] In step S5 shown in FIG. 2, the lower end of the flat mold 1 inserted into the rectangular portion M4 is sized to match the shape of the shoulder in the invert IN shown in FIG. 1, and the flat mold 1 is temporarily pulled up to the ground. On the ground, the lower end of the flat mold 1 is machined to match the shape of the shoulder, and at the positions of the inflow pipe IP and the outflow pipe OP, it is cut out to match those pipes.

[0057] When the machining of the lower end is completed, the flat mold 1 is inserted again through the opening of the manhole inlet Mi.

[0058] In step S6, the flat mold 1 is installed on the vertical walls (front wall, left and right side walls, rear wall) of the rectangular portion M4. Taking the front wall M4F of the rectangular portion M4 shown in FIG. 1(A) as an example, the first flat mold 1-1 is arranged so that the end portion (the end portion of the flat portion 10) opposite to the bifurcated portion 20 of the first flat mold 1-1 abuts against the left vertical edge M4e1. When the first flat mold 1-1 is arranged, the screw holes 222 shown in FIG. 3(A) are drilled in the wrap portion 22 of the bifurcated portion 20 in the first flat mold 1-1, screws are driven into the front wall M4F, and the first flat mold 1-1 is temporarily fixed with screws. Also, screw holes may be drilled at a plurality of spaced positions of the flat portion 10, and the flat portion 10 may also be temporarily fixed to the front wall M4F with screws. Note that the temporary fixing of the flat portion 10 with screws is omitted in the description of the second and subsequent flat molds, but it may be performed in the same manner.

[0059] Next, the pressing jig is set.

[0060] FIG. 4 is a view of the state in which the holding jig is set, taken from above after cross-sectioning in the horizontal direction. In this FIG. 4, the upper side of the figure is the front wall M4F. Further, the flat mold 1 extends to the back side of the paper surface, and the protruding strip portion 11 is also shown in FIG. 4.

[0061] First, an anchor hole 13 indicated by a dotted line in FIG. 3(A) is drilled in the central portion in the width direction of the flat plate portion 10. At this time, an injection hole 12 indicated by a dotted line in FIG. 3(A) is also drilled in alignment with the upper end portion of the flat plate portion 10.

[0062] Next, an anchor AC is driven into the front wall M4F from the anchor hole 13. The anchor AC remains in the front wall M4F even after the lining method is completed.

[0063] The holding jig 9 includes a connecting fitting 91, a holding plate 92, a pushing member 93, and an angle member 94.

[0064] A screw hole is provided at the tip portion of the anchor AC, and the screw portion of the connecting fitting 91 is inserted into the screw hole while turning the connecting fitting 91 so as to mesh with the screw hole. The holding plate 92 is provided with a through hole 921 through which the connecting fitting 91 passes. The connecting fitting 91 is passed through the through hole 921, and the holding plate 92 is brought into contact with the flat mold 1. The connecting fitting 91 protrudes from the holding plate 92 through the through hole 921. Here, gaps around the connecting fitting 91 are sealed with putty. That is, the gaps between the connecting fitting 91 in the through hole 921, the gaps between the connecting fitting 91 in the anchor hole 13, and the gaps between the connecting fitting 91 and the tip of the anchor AC are sealed with a putty material such as silicon. In FIG. 4, the putty material that seals these gaps is shown in gray. By sealing with the putty material, it is possible to prevent the filling material from leaking out. The connecting fitting 91 is removed from the anchor AC after construction, but if the putty material hardens and it is difficult to remove, the portion of the connecting fitting 91 protruding from the flat mold 1 is cut. Thereafter, it is preferable to coat the cut portion with a resin resistant to hydrogen sulfide. Note that a resin resistant to hydrogen sulfide may be used as the putty material.

[0065] Cover one end of the shaft portion 930 of the pushing member 93 on the protruding portion of the connecting fitting 91. A movable member 931 is passed through the shaft portion 930, and an angle member 94 is arranged between the movable member 931 and the pressing plate 92 so as to extend toward the back side of the paper surface. A screw groove 932 is provided on the other end side of the shaft portion 930. The dial 933 is fitted into the screw groove 932, and by tightening the dial 933, the movable member 931 moves toward the pressing plate 92 side, and the pressing force with which the pressing plate 92 presses the flat mold 1 against the front wall M4F becomes stronger, and the setting of the pressing jig 9 is completed. When the dial 933 is loosened, the pressing force weakens, and the pressing jig 9 is removed by removing the connecting fitting 91 from the screw hole.

[0066] Next, insert the end of the flat plate portion 10 of the second flat mold 1-2 between the bifurcated portions 20 (between the covering portion 21 and the wrapping portion 22) of the first flat mold 1-1 shown in FIG. 1(A), and arrange the second flat mold 1-2. The second flat mold 1-2 is provided with a cutout adapted to the inflow pipe IP in the previous step S5, and the second flat mold 1-2 is divided into upper and lower parts. Therefore, the upper part and the lower part will be arranged respectively. As a result, the wrapping portion 22 of the first flat mold 1-1 and the end of the flat plate portion 10 of the second flat mold 1-2 overlap. Since the lateral width of the wrapping portion 22 is 50 mm as described above, the overlapping margin where the first flat mold 1-1 and the second flat mold 1-2 overlap is 50 mm. Further, here, screw holes may be drilled in the overlapping portion of the two flat molds and screwed to the front wall M4F (the same applies hereinafter). When the arrangement of the second flat mold 1-2 divided into the upper part and the lower part is completed, anchor holes 13 are drilled in each of the upper part and the lower part, and each part is pressed by a separate pressing jig 9.

[0067] Subsequently, the end of the flat plate portion 10 of the third flat plate mold 1-3 is inserted between the bifurcated portions 20 of the second flat plate mold 1-2 shown in Fig. 1(A), and the third flat plate mold 1-3 is arranged. The overlapping margin between the second flat plate mold 1-2 and the third flat plate mold 1-3 is also 50 mm. When the arrangement of the third flat plate mold 1-3 is completed, the pressing jig 9 is set in the same manner as described above.

[0068] Up to this point, the portion from the left vertical edge M4e1 to 1850 mm is covered by the flat plate mold 1. For the remaining 150 mm, the mold piece 2 for width adjustment is used. This mold piece 2 for width adjustment is prepared by processing a flat plate mold (for example, a flat plate mold with a width of 300 mm) on-site. That is, the flat plate mold is cut at a position leaving 150 mm in the lateral direction from the end of the flat plate portion 10. As a result, a mold piece 2 for width adjustment with a width of 150 mm is obtained. The mold piece 2 for width adjustment is inserted between the bifurcated portions 20 of the third flat plate mold 1-3. By doing so, the mold piece 2 for width adjustment abuts against the right vertical edge M4e2, and the front wall M4F of the rectangular portion M4 is covered from the inside by the mold without gaps. Bore holes for screws may also be drilled in the mold piece 2 for width adjustment, and the mold piece 2 for width adjustment may also be screwed to the front wall M4F. Also, the pressing plate 92 of the pressing jig 9 that presses the third flat plate mold 1-3 may be widened, and the mold piece 2 for width adjustment together with the third flat plate mold 1-3 may be pressed by the pressing plate 92. Alternatively, anchor holes may be drilled in the mold piece 2 for width adjustment, and anchor AC may be driven in from the anchor holes, and the pressing jig 9 may also be set on the mold piece 2 for width adjustment.

[0069] For the mold that covers the front wall M4F of the rectangular portion M4 without gaps from the inside, the pressing jig 9 is set so that as many portions as possible are covered by the pressing plate 92, excluding the portions where the flat plate molds 1 overlap each other and the portions where the flat plate mold 1 and the mold piece 2 for width adjustment overlap each other. However, the location where the injection hole to be described later is drilled is not covered by the pressing plate 92.

[0070] When the installation of the flat mold 1 on the front wall M4F of the rectangular portion M4 is completed, the flat mold 1 is similarly installed on the remaining three vertical walls (right side wall M4R, rear wall, left side wall), and step S6 is completed.

[0071] When the installation of the flat mold 1 on the vertical walls of the rectangular portion M4 is completed, joint processing is performed on the vertical walls of the rectangular portion M4 (step S7).

[0072] FIG. 5 is a view of the overlapping portion of the flat molds 1 taken in a horizontal cross-section and viewed from above. In this FIG. 5 as well, the upper side of the figure is the front wall M4F, similar to the previous FIG. 4. Hereinafter, the front wall M4F side may be referred to as the outer side, and the opposite side may be referred to as the inner side. Also, the flat mold 1 extends to the back side of the paper surface. Further, in this FIG. 5 as well, the filling space S between the flat mold 1 and the front wall M4F is shown.

[0073] In FIG. 5(A), the bifurcated portion 20 of the flat mold 1 shown on the left side is shown. Of the covering portion 21 and the wrapping portion 22 that constitute the bifurcated portion 20, the shorter covering portion 21 is located on the inner side, and the longer wrapping portion 22 is located on the outer side. The length in the lateral width direction of the wrapping portion 22 is 50 mm, while the length in the lateral width direction of the covering portion 21 is 10 mm. That is, the length in the lateral width direction of the covering portion 21 is 1 / 5 of the length in the lateral width direction of the wrapping portion 22.

[0074] Also, in FIG. 5(A), the sheet GC of the glass roving cloth (woven fabric) described with reference to FIG. 3(B) is schematically shown. The sheet GC of the glass roving cloth is provided from the vicinity of the bifurcated portion 20 of the flat portion 10 in the flat mold 1 shown on the left side, through the connecting portion 23, to the leading edge 22e of the wrapping portion 22. Note that the sheet GC of the glass roving cloth may be provided only up to the middle of the wrapping portion 22 instead of up to the leading edge 22e of the wrapping portion 22. That is, the sheet GC of the glass roving cloth may be provided at a location around the connecting portion including the connecting portion 23, from the portion of the flat portion 10 on the connecting portion 23 side to the portion of the wrapping portion 22 on the connecting portion 22 side.

[0075] The end 15 of the flat part 10 of the flat mold 1 shown on the right side is inserted between the bifurcated parts 20 of the flat mold 1 shown on the left side (between the covering part 21 and the wrapping part 22) until the edge 15e of the end 15 abuts against the connecting part 23. The end 15 overlaps the covering part 21 by 10 mm and overlaps the wrapping part 22 by 50 mm. The flat mold 1 remains in place even after the lining method is completed, and the inner surface of the flat mold 1 becomes the new inner wall of the rectangular part M4.

[0076] External forces such as earth pressure and earthquake are applied to the remaining flat mold 1, generating tensile forces. As shown by the thick arrows in Fig. 5(A), the end 15 of the flat part 10 of the flat mold 1 shown on the right side may be deformed so as to turn up inward. Against this deformation, instead of relying only on the adhesive force of the resin, the presence of the covering part 21 enables the end 15 to be held down, suppressing this deformation. To ensure the overlap between the covering part 21 and the end 15 of the flat part 10 of the flat mold 1 shown on the right side, the length of the covering part 21 in the lateral direction needs to be at least 1 / 5 of the length of the wrapping part 22 in the lateral direction. Also, as the length of the covering part 21 in the lateral direction capable of holding down the end 15, it is necessary that it is at least 1 / 5 of the length of the wrapping part 22 in the lateral direction. Further, tensile forces also act on the outer wrapping part 22. However, since the sheet GC of glass roving cloth has higher strength than the sheet GM of chopped strand mat, the presence of this sheet GC of glass roving cloth in the wrapping part 22 enables it to resist the tensile force and prevent the cured resin from being destroyed. Also, although the flat part 10 and the part from the flat part 10 to the covering part 21 are flat, the boundary between the flat part 10 and the connecting part 23 and the boundary between the connecting part 23 and the wrapping part 22 are bent and are easily affected by the tensile force. Sheets GC of glass roving cloth are provided at these boundaries to reinforce these boundaries.

[0077] As described above, a resin-supported sheet 30 is attached to the inner surface (the surface on the covering portion 21 side) of the wrap portion 22 with a double-sided tape 31. The thickness of the resin-supported sheet 30 is 1 mm, and the end portion 15 of the flat portion 10 of the flat mold 1 shown on the right faces the wrap portion 22 through the resin-supported sheet 30. That is, the inner surface (the other surface 30b) of the resin-supported sheet 30 with a thickness of 1 mm is in contact with the end portion 15 of the flat portion 10 of the flat mold 1 shown on the right. In the resin-supported sheet 30, one surface 30a is located on the wrap portion 22 side, and the other surface 30b is located on the end portion 15 side of the flat portion 10 of the flat mold 1 shown on the right.

[0078] Also, in this Figure 5 as well, the primer layer PM is indicated by a cross mark. This primer layer PM is provided on the outer surface of the flat mold 1 shown on the left. It is also provided on the inner peripheral surface of the bifurcated portion 20. Further, it is also provided on the outer surface of the flat mold 1 shown on the right. In addition, the primer layer PM is provided on the edge 15e of the end portion 15 in the flat portion 10 of the flat mold 1 shown on the right, and is also provided on the surface of the end portion 15 facing the covering portion 21.

[0079] In the stage of installing the flat mold 1 in step S6, immediately before inserting the end of the flat part 10 of the other flat mold 1 between the bifurcated parts 20 of one flat mold 1, the resin support sheet 30 is made to contain a resin mainly composed of a vinyl ester resistant to hydrogen sulfide. The gap GL between the portion of the end 15 in the flat part 10 of the flat mold 1 shown on the right side, which faces the covering part 21, and the covering part 21 is 1 mm. In the joint treatment in step S7, a resin mainly composed of vinyl ester is pushed into this gap GL with a spatula, and an operation is performed to level the resin overflowing from this gap GL. In FIG. 5, the resin is represented by fine dots. The resin contained in the resin support sheet 30 does not easily drip downward, oozes out from both surfaces 30a and 30b of the resin support sheet 30 respectively, and the gap between the wrap part 22 of the flat mold 1 shown on the left side and the end 15 of the flat part 10 of the flat mold 1 shown on the right side is filled with the resin, and the wrap part 22 of the flat mold 1 shown on the left side and the end 15 of the flat part 10 of the flat mold 1 shown on the right side are firmly adhered over a length of 50 mm. Also, the sealing property is improved, and it is possible to prevent hydrogen sulfide from entering up to the filler and corroding even the filler.

[0080] Note that in FIG. 5(A), the flat mold 1 is shown on the right side, but the same applies to the mold piece 2 for width adjustment.

[0081] When the joint treatment on the front wall M4F of the rectangular part M4 is completed, the joint treatment is similarly performed on the remaining three vertical walls (the right side wall M4R, the back wall, and the left side wall), and step S7 is completed.

[0082] When the joint treatment on the vertical wall of the rectangular part M4 is completed, the filling space S secured by the protruding part 11 is filled with a filler between the vertical wall of the rectangular part M4 and the flat mold 10 (step S8 shown in Fig. 2). As described above, when drilling the anchor holes 13, the injection holes 12 (see Fig. 3(A)) are also drilled at the upper ends of the flat parts 10 of each flat mold 1. Note that the injection holes 12 do not need to be drilled in all the flat molds 1 and the mold pieces 2 for width adjustment. Instead, they may be drilled at only one location (for example, the front wall M4F) or at two locations for one wall. Also, the injection holes 12 may be drilled at a timing different from that of drilling the anchor holes 13 (for example, immediately before filling the filler).

[0083] As the filler, a room-temperature curing resin mainly composed of an epoxy resin is used, and the filler is injected into the filling space S from the injection holes 12 by the force of a pump, one wall at a time. For example, in the filling space of the front wall M4F, in the first injection, the resin is filled up to about 300 mm in height, in the second injection, up to about 700 mm in height, in the third injection, up to about 1100 mm in height, and finally up to 1500 mm. Next, the resin is injected into the filling space S of the right side wall M4R in four divided times in the same way, the resin is injected into the filling space S of the back wall in four divided times in the same way, and finally the resin is injected into the filling space S of the left side wall in four divided times in the same way. Although the resin injection is carried out in multiple times in this way, the amount of the first injection is made the least to surely form the part serving as the bottom foundation. Also, there is a meaning to confirm that there is no leakage of the filler from the bottom, so the amount of the first injection is reduced. For the filling of the filler in the vertical wall, the filler may be injected by its own weight without using a pump.

[0084] Note that the pressing jig is removed after the filled resin is completely cured.

[0085] Subsequently, a flat mold that covers the top plate of the rectangular portion M4 from the inside is inserted through the opening of the manhole inlet Mi (step S9). Since the flat mold that covers the top plate of the rectangular portion M4 from the inside has a width of 350 mm, it can be easily inserted through the opening of the manhole inlet Mi. The flat mold that covers the top plate of the rectangular portion M4 from the inside is horizontally installed and thus receives the weight of the filling material. Even if it is pressed by a pressing jig as described later, with a width of 650 mm, the flat mold itself is likely to sag downward. Therefore, a flat mold with a narrower width than the vertically arranged flat mold 1 is used. The difference between the flat mold with a width of 350 mm and the flat mold with a width of 650 mm shown in Fig. 3(A) is that the flat portion of the 350-mm flat mold is only 300 mm shorter than the flat portion of the 650-mm flat mold. Hereinafter, components with the same names as the components of the flat mold with a width of 650 mm shown in Fig. 3(A) will be described with the same reference numerals as those previously assigned.

[0086] At the portion of the flat mold inserted into the rectangular portion M4 that comes to the position connecting to the straight wall portion M3 shown in Fig. 1, the dimension of the inner diameter DL of the straight wall portion M3 is measured. The flat mold after the dimension measurement is once lifted up to the ground, and the flat mold is subjected to a cutting process so as to match the inner diameter DL of the straight wall portion M3 (step S10).

[0087] When the process in step S10 is completed, the flat mold is inserted again through the opening of the manhole inlet Mi.

[0088] In step S11, a flat mold is installed on the top plate Mt of the rectangular portion M4. Referring to FIG. 1(A), the first flat mold 6-1 is arranged such that the end portion (the end portion of the flat portion 10) on the side opposite to the bifurcated portion 20 of the first flat mold 6-1 abuts against the edge Mte1 on one side of the top plate Mt, and the first flat mold 6-1 is temporarily fixed to the top plate Mt with screws. Next, anchor holes are drilled in the central portion in the lateral width direction of the flat portion 10. Subsequently, anchors are driven into the top plate Mt through the anchor holes drilled in the flat portion 10, and the flat mold 6-1 is pressed by a pressing jig. The pressing jig used here has the same configuration as the pressing jig 9 described with reference to FIG. 4, but the width of the pressing plate is narrower than the width of the pressing plate 92 shown in FIG. 4.

[0089] Next, the end portion of the flat portion 10 of the second flat mold 6-2 is inserted between the bifurcated portions 20 of the first flat mold 6-1. This time, the second flat mold 6-2 is screwed, and further, anchor holes are drilled and the second flat mold 6-2 is pressed by a pressing jig. Thereafter, the same operation is repeated until the end portion of the flat portion 10 of the fifth flat mold 6-5 is inserted between the bifurcated portions 20 of the fourth flat mold 6-4. The fifth flat mold 6-5 is provided with a cutout adapted to the straight wall portion M3 in the previous step S10, and the fifth flat mold 6-5 is divided into left and right parts. Therefore, the left and right parts are respectively inserted between the bifurcated portions 20 of the fourth flat mold 6-4. Then, the left and right parts are respectively screwed, and further, anchor holes are drilled in each part, and each part is pressed by a separate pressing jig. The sixth flat mold 6-6 is the same as the fifth flat mold 6-5. Finally, a mold piece 7 for width adjustment for the remaining 150 mm is cut out, and the end portion of the mold piece 7 for width adjustment is inserted between the bifurcated portions 20 of the sixth flat mold 6-6 which is divided into left and right parts. After this mold piece 7 is also screwed, the mold piece 7 is also pressed by a pressing jig.

[0090] In step S12, joint treatment is performed on the top plate Mt of the rectangular portion M4. The joint treatment here also uses a resin mainly composed of vinyl ester as the joint material. Although the front wall M4F, which is a vertical wall, was shown in Fig. 5(A), this front wall M4F can be replaced with the top plate Mt, which is a horizontal wall. The following description will continue with reference to Fig. 5(A). In the flat mold installed on the top plate Mt of the rectangular portion M4, the joint material is more likely to drip than in the flat mold installed on the vertical wall, and the effect of the resin support sheet 30 is exerted. That is, if the resin support sheet 30 is filled with resin so as to completely fill the communication space of the resin support sheet 30, although there is no resin oozing upward, the resin flowing downward is blocked by the end portion 15 of the flat plate portion 10 in the inserted flat mold shown in Fig. 5(A). For this reason, the gap between the lap portion 22 of the flat mold shown on the left side and the end portion 15 of the flat plate portion 10 of the flat mold shown on the right side is filled with resin, and the lap portion 22 of the flat mold shown on the left side and the end portion 15 of the flat plate portion 10 of the flat mold shown on the right side are firmly adhered over a length of 50 mm. Also, the sealing performance is improved. Further, in the joint treatment of step S12, resin is pushed into the gap GL shown in Fig. 5(A) with a spatula, and an operation is performed to level the resin that is about to drip from this gap GL.

[0091] In step S13 shown in FIG. 2, a filler is filled into the filling space S secured by the protruding portion 11 between the top plate of the rectangular portion M4 and the flat mold 10. When filling the filler, an injection hole for injecting the filler is drilled. The injection hole here is drilled at one end side in the longitudinal direction orthogonal to the width direction of the flat mold or the mold piece for width adjustment. Since the top plate Mt is a horizontal wall, unlike the vertical wall, it is difficult to fill the filler. Even if an attempt is made to fill the filler from the central portion in the longitudinal direction, the flow path of the filler is not determined, and the filling does not succeed well. When filling from one end side in the longitudinal direction, the filling space expands toward the other end side, and the filler is injected toward the other end side by the pressure of the pump. In addition, the protruding portion 11 provided on the outer surface OS of the flat mold and extending from one end side to the other end side may be made to gradually increase the protruding amount from one end side to the other end side so as to ensure an inclination. However, even if it is called an inclination, it is a very slight inclination with an inclination angle of about several degrees. Further, the injection holes do not have to be drilled in all the flat molds and the mold pieces for width adjustment, and may be drilled at only one location or may be drilled every other one. However, since the wrap portion 22 is closer to the manhole M side as described above, the filling space S is also thinner accordingly. In order to more surely distribute the filler to this thinner portion, it is preferable to drill injection holes in all the flat molds. Further, when drilling the anchor holes in step S9, the injection holes may be drilled together.

[0092] Also, as the filler here, a room temperature curable resin mainly composed of an epoxy resin is used, and the filler is injected in multiple portions by the force of the pump from the injection hole. That is, the resin is pushed from the one end side provided with the injection hole toward the other end side, and the curing of the resin proceeds from the other end side toward the one end side.

[0093] Note that the pressing jig is removed after the filled resin is completely cured.

[0094] Next, install the straight-wall mold (step S14). The straight-wall mold is a cylindrical one installed inside the straight-wall portion M3 shown in FIG. 1, but it is an arc-shaped sheet body at the stage of being inserted from the opening of the manhole inlet Mi. That is, it is inserted from the opening of the manhole inlet Mi in a reduced-diameter state where the circumferential ends of the arc-shaped sheet body are overlapped. This sheet body for the straight-wall mold is also made of a resin with vinyl ester as the main component, and protruding portions protruding outward are evenly distributed at intervals.

[0095] Fit the lower end of the sheet body for the straight-wall mold inserted into the manhole inside the opening Mto (see FIG. 1) that connects the rectangular portion M4 and the straight-wall portion M3 of the top plate Mt. The operator expands the sheet body by hand until the protruding portions of the straight-wall mold contact the inner peripheral wall of the straight-wall portion. The sheet body becomes a cylindrical straight-wall mold with one circumferential end overlapping the other. Then, in a state where one circumferential end overlaps the other, anchor bolts are driven into the inner peripheral wall of the straight-wall portion M3 at some of the protruding portions selected to be evenly scattered in the circumferential direction among the plurality of provided protruding portions, and the straight-wall mold is fixed to the inner peripheral wall of the straight-wall portion M3. Next, install a pressing jig on the inner peripheral side of the straight-wall mold. Although the straight-wall mold is fixed to the inner peripheral wall of the straight-wall portion M3 with anchor bolts, when the filling material is filled into the filling space secured by the protruding portions between the inner peripheral wall of the straight-wall portion M3 and the straight-wall mold, the straight-wall mold may bulge inward or collapse due to the weight of the filling material, and it is necessary to press the straight-wall mold from the inside with the pressing jig. When the installation of the pressing jig is completed, step S14 is completed.

[0096] In step S15, joint treatment of the straight-wall mold is performed. Also in the joint treatment here, a resin with vinyl ester as the main component is used.

[0097] When the joint process in step S15 is completed, a filler is filled into the filling space secured by the protruding portion between the inner peripheral wall of the straight wall portion M3 and the straight wall mold (step S16). Here too, as the filler, a room temperature curable resin mainly composed of epoxy resin is used. The filler is poured into the filling space by utilizing gravity from between the upper edge of the straight wall mold and the inner peripheral wall of the straight wall portion M3.

[0098] In step S17, an inclined wall mold is installed. The inclined wall mold is formed by combining a plurality of divided sheet bodies. The inclined wall mold is installed inside the height adjusting member M1 and the inclined wall portion M2 shown in Fig. 1(B). The collar mold installed inside the height adjusting member M1 is a sheet body made of resin mainly composed of arc-shaped vinyl ester, similar to the sheet body of the straight wall mold. However, the lower end portion is bent radially outward and extends obliquely downward. Further, on this sheet body, protrusions are evenly provided at intervals in the circumferential direction immediately above the bent lower end portion. The main body mold installed inside the inclined wall portion M2 is a sheet body made of resin mainly composed of vinyl ester, which is divided into a plurality of pieces in the circumferential direction.

[0099] In step S17, first, the sheet body of the collar mold is inserted from the opening of the manhole inlet Mi in a reduced diameter state with both circumferential ends overlapped. Next, the operator expands the sheet body of the collar mold by hand until the protrusion abuts against the inner peripheral wall of the height adjusting member M1 inside the height adjusting member M1, and the sheet body becomes a cylindrical collar mold with one circumferential end overlapping the other end. In this state, anchor bolts are driven into the inner peripheral wall of the height adjusting member M1 at some or all of the plurality of provided protrusions. As a result, the collar mold is fixed to the inner peripheral wall of the height adjusting member M1 with the filling space secured.

[0100] Next, insert the sheet body of the main body mold through the opening of the manhole inlet Mi. The sheet body of the main body mold is divided into a plurality (here, three) in the circumferential direction. Hereinafter, the sheet body divided into three will be referred to as the first sheet body, the second sheet body, and the third sheet body. First, fit the lower end portion of the first sheet body inside the upper end portion of the straight wall mold, and drive an anchor bolt into the fitted portion. Next, arrange the second sheet body so that one end portion in the circumferential direction of the first sheet body overlaps with the other end portion in the circumferential direction of the second sheet body. Also for the second sheet body, fit the lower end portion inside the upper end portion of the straight wall mold, and drive an anchor bolt into the fitted portion. Finally, arrange the third sheet body between the other end portion in the circumferential direction of the first sheet body and one end portion in the circumferential direction of the second sheet body. One end portion in the circumferential direction of the third sheet body overlaps with the other end portion in the circumferential direction of the first sheet body, and the other end portion in the circumferential direction of the third sheet body also overlaps with one end portion in the circumferential direction of the second sheet body. Also for the third sheet body, fit the lower end portion inside the upper end portion of the straight wall mold, and drive an anchor bolt into the fitted portion. The outer peripheral surfaces of the upper edge portions of the first sheet body, the second sheet body, and the third sheet body respectively come into contact with the inner peripheral surface of the lower end portion of the previously installed neck mold.

[0101] The first sheet body, the second sheet body, and the third sheet body are not provided with protruding portions, but the upper end portion of the straight wall mold into which the lower end portions of each are fitted is provided with protruding portions, and the filling spaces of the lower portions of each of the three sheet bodies are ensured by these protruding portions. On the other hand, the filling spaces of the upper portions of each of the three sheet bodies are ensured by the protruding portions of the neck mold.

[0102] In step S18, perform the joint treatment of the inclined wall mold. In the joint treatment of the inclined wall mold, perform joint treatment on the portions where one end portion and the other end portion in the circumferential direction of the sheet body of the neck mold overlap, the portion where the first sheet body and the second sheet body overlap in the circumferential direction, the portion where the second sheet body and the third sheet body overlap in the circumferential direction, and the portion where the first sheet body and the third sheet body overlap in the circumferential direction. Also here, as the joint material, a resin mainly composed of a vinyl ester resistant to hydrogen sulfide is used.

[0103] Note that the inclined wall mold may be an arcuate sheet body that is not obtained by dividing the main body mold into three parts and is integrated with the neck mold.

[0104] When the joint treatment of the inclined wall mold is completed, a filler is filled into the filling space secured by the protruding portion between the inner peripheral walls of the height adjustment member M1 and the inclined wall portion M2 and the inclined wall mold (step S19). The filling of the filler here is a continuation of the filling of the filler in step S16, and the same filler as that used in step S16 is poured using gravity. When the filler is filled up to the upper edge of the neck mold, a sealing treatment is performed with a putty mainly composed of a vinyl ester resistant to hydrogen sulfide, which is the same as the joint material used in the joint treatment, and step S19 ends.

[0105] In step S20, machining is performed from the inner peripheral surface of the mold to install a new footrest fitting. Also, the inner peripheral surface of the mold is cleaned. Thus, the manhole lining method is completed.

[0106] By the manhole lining method described above, a manhole lining structure covering the inner peripheral wall of the manhole M is completed. In the completed manhole lining structure, the strength is maintained by various molds such as the flat molds 1 and 6 and the cured filler, and the inner surfaces of the various molds become the new inner walls of the manhole with a backing.

[0107] In the vertical walls (front wall M4F, right side wall M4R, back wall, left side wall) of the rectangular portion M4 of the present embodiment, the tensile strength of the overlapping portions of the flat molds 1 and the tensile strength of the overlapping portions of the flat molds 6 in the ceiling wall (top plate Mt) of the rectangular portion M4 have been confirmed to be improved to the same level as the tensile strength of the flat portions 10 of the flat molds 1 and 6. Contributing to this effect are the adhesion by the resin retained by the resin support sheet 30 described above, the pressing by the covering portion 21, and the reinforcement by the glass roving cloth sheet GC of the lap portion. By improving the tensile strength, the resin cured at the overlapping portions of the flat molds is less likely to be broken. As a result, the sealing property is maintained, and it is possible to prevent hydrogen sulfide from entering the filler and corroding even the filler.

[0108] FIG. 5(B) is a view of a first modification of the structure of the overlapping portions of the flat molds, sectioned horizontally in the same manner as in FIG. 5(A) and viewed from above. Hereinafter, the description will focus on the differences from the example shown in FIG. 5(A). Also, components having the same name as the components described so far will be described with the same reference numerals as those given so far.

[0109] The length of the covering portion 21 in the lateral width direction shown in Fig. 5(A) was 10 mm, whereas the length of the covering portion 21 in the lateral width direction in this first modification example is 25 mm, which is half of the length of the 50 mm wrap portion 22. In a flat mold with a height of 3000 mm, for example, even if the end portion 15 of the flat portion 10 of the other flat mold is firmly inserted into the bifurcated portion 20 of one flat mold at the upper part, there is a risk that the other flat mold will slip out just by being slightly inclined at the lower part. In order to ensure that it is inserted firmly over the entire height, the length of the covering portion 21 in the lateral width direction is set to 25 mm in this first modification example. Note that the longer the length of the covering portion 21 in the lateral width direction, the more difficult it becomes to insert the other flat mold into the bifurcated portion 20. Moreover, not only does it become difficult to manufacture the bifurcated portion 20 itself, but it also becomes difficult to perform the operation of attaching the resin support sheet 30 and the operation of incorporating resin into the attached resin support sheet 30. For these reasons, it is preferable to keep the length of the covering portion 21 in the lateral width direction at 1 / 2 or less of the length of the wrap portion 22 in the lateral width direction.

[0110] Further, the first modification example is an example in which the resin-supported sheet 30 is attached to the inner peripheral surface of the bifurcated portion 20 as much as possible. That is, in addition to the inner peripheral surface of the wrap portion 22 (the surface on the covering portion 21 side), the resin-supported sheet 30 is attached to the inner peripheral surface of the connecting portion 23 and the inner peripheral surface of the covering portion 21 (the surface on the wrap portion 22 side) with double-sided tape 31. The thickness of each resin-supported sheet 30 is 1 mm. The resin-supported sheet 30 provided on the inner peripheral surface of the wrap portion 22 contacts the outer surface of the end portion 15 of the flat portion 10 of the flat mold 1 shown on the right side. The resin-supported sheet 30 provided on the inner peripheral surface of the connecting portion 23 contacts at least a part of the edge 15e of the end portion 15 in the flat portion 10 of the flat mold 1 shown on the right side. The resin-supported sheet 30 provided on the inner peripheral surface of the covering portion 21 contacts the inner surface of the end portion 15 in the flat portion 10 of the flat mold 1 shown on the right side. The resin contained in each resin-supported sheet 30 does not easily drip downward, oozes out from both sides of each resin-supported sheet 30, and the gap between the inner peripheral surface of the bifurcated portion 20 of the flat mold 1 shown on the left side and the end portion 15 of the flat portion 10 of the flat mold 1 shown on the right side is filled with resin, and the bifurcated portion 20 of the flat mold 1 shown on the left side and the end portion 15 of the flat portion 10 of the flat mold 1 shown on the right side are firmly adhered as a whole. Also, the sealing property is improved, and it is possible to prevent hydrogen sulfide from entering the filler and corroding even the filler.

[0111] Further, in the first modification example, a glass roving cloth (woven fabric) sheet GC is provided at a location around the connecting portion including the connecting portion 23 from the boundary between the flat portion 10 and the connecting portion 23 to the boundary between the connecting portion 23 and the wrap portion 22. The bent portion that is easily affected by the tensile force is reinforced by the glass roving cloth sheet GC, and it is possible to resist the tensile force caused by earth pressure, earthquake, etc. Also, the connecting portion 23 is reinforced by the glass roving cloth sheet GC. Note that in the wrap portion 22, the glass roving cloth sheet GC may be provided up to the same position as the position of the leading edge 21e of the covering portion 21.

[0112] FIG. 6 is a view of a horizontally cross-sectioned structure of a portion where flat molds overlap each other as viewed from above, similar to FIG. 5(A). The upper side of the figure is the inner wall M4I side of the rectangular portion. Hereinafter, this inner wall M4I side may be referred to as the outer side, and the opposite side may be referred to as the inner side. Hereinafter, the description will focus on the differences from the example shown in FIG. 5(A). Also, components having the same name as the components described so far will be described with the same reference numerals as those previously assigned.

[0113] FIG. 6(A) is a view showing a second modification.

[0114] Even in the second modification, it has a covering portion 21 with a width of 10 mm and a wrapping portion 22 with a width of 50 mm. In this second modification, the covering portion 21 does not extend directly from the flat portion 10, but protrudes in the width direction while maintaining a parallel relationship with the wrapping portion 22 at a position approximately 2 mm inward from the flat portion 10. On the other hand, the wrapping portion 22 extends in the width direction while maintaining a parallel relationship with the covering portion 21 at a position approximately 2 mm outward from the flat portion 10. The connecting portion 23 is a portion that connects the flat portion 10, the covering portion 21, and the wrapping portion 22 respectively.

[0115] In this second modified example as well, similar to the first modified example, it is an example where the resin-supporting sheet 30 is attached to the inner peripheral surface of the bifurcated portion 20 as much as possible. That is, the resin-supporting sheet 30 is attached to the inner peripheral surface of the wrap portion 22 (the surface on the covering portion 21 side), the inner peripheral surface of the connecting portion 23, and the inner peripheral surface of the covering portion 21 (the surface on the wrap portion 22 side) with double-sided tape 31. The edge 15e of the end portion 15 in the flat plate portion 10 of the flat plate mold 1 shown on the right abuts against the resin-supporting sheet 30 attached to the inner peripheral surface of the connecting portion 23. The resin-supporting sheet 30 provided on the inner peripheral surface of the wrap portion 22 is in contact with the outer surface of the end portion 15 of the flat plate portion 10 of the flat plate mold 1 shown on the right. The resin-supporting sheet 30 provided on the inner peripheral surface of the connecting portion 23 is in contact with the entire edge 15e of the end portion 15 in the flat plate portion 10 of the flat plate mold 1 shown on the right. The resin-supporting sheet 30 provided on the inner peripheral surface of the covering portion 21 is in contact with the inner surface of the end portion 15 in the flat plate portion 10 of the flat plate mold 1 shown on the right. The resin contained in each resin-supporting sheet 30 is not likely to drip downward, oozes out from both sides of each resin-supporting sheet 30, and the gap between the inner peripheral surface of the bifurcated portion 20 of the flat plate mold 1 shown on the left and the end portion 15 of the flat plate portion 10 of the flat plate mold 1 shown on the right is filled with resin, and the bifurcated portion 20 of the flat plate mold 1 shown on the left and the end portion 15 of the flat plate portion 10 of the flat plate mold 1 shown on the right are firmly adhered as a whole. Also, the sealing property is improved.

[0116] Also, in this second modified example, a primer layer PM is provided on the outer surface OS of the flat plate mold 1 that contacts the filler, but it is not provided on the inner peripheral surface of the bifurcated portion 20. In the example shown in Fig. 5(A) as well as in the first modified example, the primer layer PM may be provided on the outer surface OS of the flat plate mold 1 that contacts the filler and not provided at locations where there is no possibility of contacting the filler. Or conversely, in the second modified example, the primer layer PM may also be provided on the inner peripheral surface of the bifurcated portion 20.

[0117] Furthermore, in the second modification example, a glass roving cloth (woven fabric) sheet GC is also provided on the covering portion 21. That is, the glass roving cloth sheet GC shown in Fig. 6(A) is provided from the vicinity of the bifurcated portion 20 of the flat plate portion 10 in the flat plate mold 1 shown on the left side, through the connecting portion 23, to the leading edge 21e of the covering portion 21 and up to the middle of the wrapping portion 22. Also in the second modification example, the strength of the wrapping portion 22 is improved by the glass roving cloth sheet GC, and it can resist tensile forces caused by earth pressure, earthquakes, etc. Furthermore, the strength of the covering portion 21 is also improved by the glass roving cloth sheet GC. For this reason, a deformation in which the end portion 15 of the flat plate portion 10 of the flat plate mold 1 shown on the right side is turned up inward (refer to the thick arrow shown in Fig. 5(A)) due to earth pressure, earthquakes, etc. can be more reliably suppressed by this covering portion 21. Note that the glass roving cloth sheet GC is provided for the same length on the covering portion 21 and the wrapping portion 22, but the glass roving cloth sheet GC may be provided up to the leading edge 22e of the wrapping portion 22. Also, in the second modification example, the covering portion 21 is closer to the inside from the flat plate portion 10. For this reason, in addition to the portion from the bifurcated portion 20 side of the flat plate portion 10 to the flat plate portion 10 side portion of the wrapping portion 22, the glass roving cloth sheet GC is also provided at the portion from the bifurcated portion 20 side of the flat plate portion 10 to the flat plate portion 10 side portion of the covering portion 21 to reinforce those portions.

[0118] Fig. 6(B) is a view showing a third modification example.

[0119] Even in the third modification example, it has a covering portion 21 and a wrapping portion 22. In this third modification example, in the flat mold 1 shown on the left side, the flat plate portion 10, the wrapping portion 22, and the connecting portion 23 connecting the flat plate portion 10 and the wrapping portion 22 are integrally formed, but the covering portion 21 is a separate body. That is, the covering portion 21 of the third modification example has a structure in which three sheets of chopped strand mat (non-woven fabric) are stacked and solidified with a resin mainly composed of vinyl ester, and the lateral width is 30 mm. The length of the portion overlapping the wrapping portion 22 is 15 mm. Note that this separate covering portion 21 may be one in which a glass roving cloth (woven fabric) sheet is disposed between the chopped strand mat sheets.

[0120] On the outer surface of the covering portion 21 shown in FIG. 6(B), a resin-supporting sheet 30 with a lateral width of about 30 mm is attached with a double-sided tape 31. In the joint treatment of the flat mold, a resin mainly composed of vinyl ester is included in this resin-supporting sheet 30, and the covering portion 21 is attached from the inside so as to straddle the flat plate portion 10 of the left flat mold 1 and the flat plate portion 10 of the right flat mold 1, thereby performing the joint treatment. The resin contained in the resin-supporting sheet 30 attached to the separate covering portion 21 also does not easily drip downward, oozes out from both sides of this resin-supporting sheet 30, and the resin fills from the inner surface of the flat plate portion 10 of the flat mold 1 shown on the left side to the inner surface of the end portion 15 of the flat plate portion 10 of the flat mold 1 shown on the right side. As a result, the three parts, i.e., the flat plate portion 10 of the flat mold 1 shown on the left side, the end portion 15 of the flat plate portion 10 of the flat mold 1 shown on the right side, and the separate covering portion 21, are firmly adhered. As a result, even if the covering portion 21 is a separate body, deformation in which the end portion 15 of the flat plate portion 10 of the flat mold 1 shown on the right side turns upward inward (refer to the thick arrow shown in FIG. 5(A)) due to earth pressure, an earthquake, or the like can be suppressed by this covering portion 21. Also, the sealing property is improved, and it is possible to prevent hydrogen sulfide from entering up to the filler and corroding even the filler. Further, in this third modification example, the operation of attaching the resin-supporting sheet 30 and the operation of including the resin in the attached resin-supporting sheet 30 are also easy to perform.

[0121] In addition, in the third modification example, the glass roving cross (woven fabric) sheet GC is provided only at two locations, namely, the boundary between the flat plate portion 10 and the connecting portion 23 and the boundary between the connecting portion 23 and the wrap portion 22. This is an example in which the expensive glass roving cross sheet GC is most conserved. However, the bent portions that are easily affected by the tensile force are reinforced by the glass roving cross sheet GC, and it is possible to resist the tensile force caused by earth pressure, earthquake, etc.

[0122] Note that the glass roving cross sheet GC may be provided only at the connecting portion 23 among the flat plate portion 10, the connecting portion 23, and the wrap portion 22. Furthermore, the glass roving cross sheet GC may be provided only at at least a part of the connecting portion instead of the entire connecting portion 23.

[0123] Note that a sheet of glass roving cross (woven fabric) may be sandwiched between sheets of chopped strand mat (non-woven fabric) on a straight wall mold or an inclined wall mold (which may be divided or integrated), and a resin mainly composed of vinyl ester may be used to solidify these three sheets.

[0124] In addition, a resin support structure (for example, a resin support sheet 30) may be provided at the overlapping portion of a straight wall mold or an inclined wall mold (which may be divided or integrated). Furthermore, a bifurcated portion 20 may be provided at one end in the circumferential direction of an arcuate straight wall mold or a neck mold, and the other end in the circumferential direction may be inserted between the bifurcated portions 20 to form a mold connection body. In this case, the base portion is the portion between one end in the circumferential direction and the other end in the circumferential direction. Alternatively, a bifurcated portion 20 may be provided at one end in the circumferential direction of each sheet body (the first sheet body, the second sheet body, the third sheet body) constituting the main body mold, and the other end of the sheet body adjacent in the circumferential direction may be inserted between the bifurcated portions 20 to form a mold connection body.

[0125] Furthermore, a grout material may be used instead of the resin as the filling material. As the grout material, a material obtained by mixing powder cement, a mixture liquid, and water on site or a premix type in which powder cement and a mixture liquid are previously blended is used.

[0126] The above description is noted below as an appendix.

[0127] (Appendix 1) A mold connecting body [for example, the connecting body of the left flat mold 1 and the right flat mold 1 shown in FIGS. 5 and 6] having a first end [for example, the wrap portion 22 shown in FIGS. 5 and 6] and a second end [for example, the end 15 of the right flat mold 1 shown in FIGS. 5 and 6] that are connected to each other and cover the inner wall of the manhole [for example, the front wall M4F, the top plate Mt] from the inside of the inner wall leaving a filling space [for example, the filling space S] therebetween. The first end and the second end overlap each other, and the overlapping portion is adhered by a resin [for example, a resin mainly composed of vinyl ester]. The mold connecting body is characterized in that the first end is provided with a resin supporting structure [for example, the resin supporting sheet 30] for supporting the resin.

[0128] When attempting to adhere the first end and the second end with resin, the resin may flow down, making it impossible to achieve sufficient adhesion and causing a significant reduction in the tensile strength of the adhered portion.

[0129] According to the mold connecting body described in Appendix 1, in the overlapping portion, the resin is likely to stay due to the resin supporting structure provided at the first end, and the first end and the second end are adhered by the retained resin, enabling sufficient tensile strength to be obtained even at the adhered portion. Also, since the resin is less likely to flow down, the sealing property is improved, and it is possible to prevent hydrogen sulfide from entering.

[0130] Note that the inner wall may be a peripheral wall or a ceiling wall.

[0131] Further, the resin support structure may be a structure (matte structure) with a recess provided on the surface of the first end portion facing the second end portion, or a structure with jagged grooves provided thereon. Further, the entire surface of the first end portion may be provided with the resin support structure.

[0132] Also, the first end portion and the second end portion may be the end portions on one side and the other side of a common mold. That is, the mold connector is formed by connecting both end portions in the circumferential direction of a single arc-shaped mold, the first end portion is one end portion in the circumferential direction of the arc-shaped mold, and the second end portion may be the other end portion in the circumferential direction of the arc-shaped mold. Alternatively, the first end portion and the second end portion may be the end portions of different molds.

[0133] (Appendix 2) The mold connector according to Appendix 1, wherein the resin is a resin resistant to hydrogen sulfide [for example, a resin mainly composed of vinyl ester].

[0134] It is preferable that both the first end portion and the second end portion are made of a material resistant to hydrogen sulfide. Also, the resin and the material may be of the same component. For example, both may be mainly composed of vinyl ester resin.

[0135] (Appendix 3) The resin support structure is a structure in which a resin support [for example, a resin support sheet 30] having a first surface [for example, one side surface 30a] located on the first end portion side and a second surface [for example, the other side surface 30b] located on the second end portion side is fixed to the first end portion [for example, a structure attached with a double-sided tape 31]. The mold connector according to Appendix 1 or 2, wherein the resin support has a communication space connecting the first surface to the second surface.

[0136] Incidentally, the resin carrier may be attached to the surface of the first end portion facing the second end portion.

[0137] Further, the mold connector may be arranged vertically, and the resin carrier may extend in the vertical direction of the mold connector. Alternatively, the mold connector may be arranged horizontally, and the resin carrier may extend in the horizontal direction of the mold connector.

[0138] Also, the communication space is not limited to a linear shape and may have a complex shape.

[0139] (Appendix 4) A first mold [for example, the left flat mold 1 shown in FIGS. 5 and 6], and A second mold [for example, the right flat mold 1 shown in FIGS. 5 and 6], and The first mold and the second mold are connected, and The first end portion [for example, the wrap portion 22] is the end portion of the first mold on the second mold side, The second end portion [for example, the end portion 15 of the right flat mold 1 shown in FIGS. 5 and 6] is the end portion of the second mold on the first mold side. The mold connector according to Appendix 1 or 2, characterized in that.

[0140] That is, it can also be applied when connecting different molds together.

[0141] (Appendix A) A mold connector [for example, the connector of the left flat mold 1 and the right flat mold 1 shown in FIGS. 5 and 6] having a first end portion [for example, the wrap portion 22 shown in FIGS. 5 and 6] and a second end portion [for example, the end portion 15 of the right flat mold 1 shown in FIGS. 5 and 6] that are connected to each other and cover the inner wall of the manhole [for example, the front wall M4F, the top plate Mt] from the inside of the inner wall leaving a filling space [for example, the filling space S] therebetween. The first end portion and the second end portion overlap each other, and the overlapping portion is adhered by a resin [for example, a resin mainly composed of vinyl ester]. The first end portion is located closer to the inner wall side than the second end portion. Furthermore, the mold connecting body is characterized in that it has a covering portion [for example, covering portion 21] that covers the second end portion from the side opposite to the inner wall side [for example, the outside] [for example, the inside].

[0142] There is a problem that the tensile strength of the overlapped and adhered portion of the mold is significantly reduced compared to the tensile strength of the mold itself that is not overlapped. Although this problem seems to be solvable by increasing the adhesive strength of the resin, there is a certain limit to increasing the adhesive strength of the resin.

[0143] According to the mold connecting body described in Supplementary Note A, even if the second end portion is likely to be turned up inward due to tensile force caused by earth pressure, earthquake, etc., the second end portion can be held by the covering portion, and the tensile strength of the overlapped and adhered portion is increased.

[0144] Note that the first end portion and the covering portion may be separate bodies.

[0145] (Supplementary Note B) A first mold [for example, the left flat mold 1 shown in FIGS. 5 and 6], and a second mold [for example, the right flat mold 1 shown in FIGS. 5 and 6], wherein the first mold and the second mold are connected, the first end portion [for example, the lap portion 22] is the end portion of the first mold on the second mold side, and the second end portion [for example, the end portion 15 of the right flat mold 1 shown in FIGS. 5 and 6] is the end portion of the second mold on the first mold side. The mold connecting body described in Supplementary Note A is characterized by this.

[0146] Note that both ends in the circumferential direction of a single arc-shaped mold are connected, the first end is one end on one side in the circumferential direction of the arc-shaped mold, and the second end may be the other end on the other side in the circumferential direction of the arc-shaped mold.

[0147] (Appendix C) The first mold has a base [e.g., flat plate portion 10], the first end [e.g., wrap portion], and the covering portion [e.g., covering portion 21], and the base, the first end, and the covering portion are integrally formed [e.g., the left flat plate mold 1 shown in FIG. 5, the left flat plate mold 1 shown in FIG. 6(A)]. The mold connector according to Appendix B, characterized in that.

[0148] Note that the base and the first end may be integral, and the covering portion may be separate from the base and the first end.

[0149] Further, the first mold may have a first connecting portion connecting the base and the first end. Furthermore, the first mold may have a second connecting portion connecting the base and the covering portion.

[0150] (Appendix D) The mold connector according to Appendix C, characterized in that the length of the covering portion extending in a direction opposite to the base is 1 / 5 or more and 1 / 2 or less of the length at the first end.

[0151] To hold down the second end where the covering portion tends to turn up inward, a length of 1 / 5 or more is required. Also, if the length of the covering portion is less than 1 / 5, as the length in the longitudinal direction orthogonal to the overlapping width of the mold connector increases, it becomes difficult for the covering portion to cover the second end over the entire length in the longitudinal direction. On the other hand, if the length of the covering portion exceeds 1 / 2, it becomes difficult to insert the first end between the covering portion and the second end.

[0152] (Appendix α) A mold [flat mold 1, flat mold 6] that covers the inner wall of a manhole [e.g., front wall M4F, top plate Mt] from the inside of the inner wall, leaving a filling space [e.g., filling space S] between the inner wall and the mold. Part [e.g., from near the bifurcated part 20 of the flat part 10, through the connecting part 23 to the leading edge 22e of the wrapping part 22] or all [e.g., over the entire flat mold 1] is a laminate of a woven fabric of glass fibers [e.g., sheet GC of glass roving cloth] and a non-woven fabric of glass fibers [e.g., sheet GM of chopped strand mat], solidified with resin. The mold is characterized by this.

[0153] (Appendix β) The resin is a resin resistant to hydrogen sulfide [e.g., [e.g., a resin mainly composed of vinyl ester]]. The mold according to Appendix α is characterized by this.

[0154] (Appendix γ) Part or all is a structure in which the woven fabric of the glass fiber is sandwiched by the non-woven fabric of the glass fiber [e.g., Fig. 3(B)]. The mold according to Appendix α or β is characterized by this.

[0155] (Appendix ε) A base part [e.g., the flat part 10 of the left flat mold 1 shown in Figs. 5 and 6, the part between the circumferential one end and the circumferential other end of the arc-shaped sheet body], and A first end part closer to the inner wall side than the base part [e.g., the wrapping part 22 of the left flat mold 1 shown in Figs. 5 and 6, the circumferential one end of the arc-shaped sheet body], and A connecting part [e.g., connecting part 23] connecting the base part and the first end part, and The first end part overlaps with a second end part located on the side opposite to the inner wall side [e.g., the end part 15 of the right flat mold 1 shown in Figs. 5 and 6, the circumferential other end of the arc-shaped sheet body]. At least, at each of the boundary between the base portion and the connecting portion and the boundary between the first end portion and the connecting portion, there is a portion where a woven fabric of glass fiber and a non-woven fabric of glass fiber are overlapped and solidified with resin (for example, FIGS. 5(A), 5(B), 6(A), 6(B)). The mold according to appended claim α or β is characterized by this.

[0156] The present invention can be variously modified within the scope described in the claims without being limited to the embodiments, modification examples, and appendices described so far. For example, it can be applied not only to manholes for sewers but also to manholes for water supply, transmission lines, communication lines, or gas pipes. Further, as the filling material, in addition to room temperature curable resins, heat curable resins, thermoplastic resins, or photocurable resins can be used by making the mold transparent. Alternatively, as described above, the filling material may be not limited to resins but may be grout materials or the like.

[0157] Also, even if it is a constituent element included only in each of the descriptions of the embodiments, modification examples, and appendices described above, the constituent element may be applied to the embodiments, other modification examples, and appendices.

Explanation of Signs

[0158] M Manhole M4 Rectangular portion M4F Front wall Mt Top plate S Filling space 1, 6 Flat mold 2, 7 Mold pieces 10 Flat plate portion 15 End portion 20 Fork portion 21 Covering portion 22 Wrapping portion 23 Connecting portion 30 Resin supporting sheet 30a One side surface 30b The other side surface GC Glass roving cloth sheet GM Chopped strand mat sheet

Claims

1. A mold that covers the inner wall of a manhole from the inside while leaving a filling space between the mold and the inner wall, wherein part or all of the mold is formed by laminating a woven fabric of glass fibers and a non-woven fabric of glass fibers and solidifying them with a resin.

2. The mold according to claim 1, wherein the resin is a resin resistant to hydrogen sulfide.

3. The mold according to claim 1 or 2, wherein part or all of the mold is formed by sandwiching the woven fabric of glass fibers with the non-woven fabric of glass fibers.

4. A base, a first end closer to the inner wall side than the base, and a connecting portion connecting the base and the first end, wherein the first end overlaps with a second end located on the side opposite to the inner wall side, and at least at the boundary between the base and the connecting portion and at the boundary between the first end and the connecting portion, there are portions formed by laminating the woven fabric of glass fibers and the non-woven fabric of glass fibers and solidifying them with a resin. The mold according to claim 1 or 2 is characterized by this.

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