JP2017128018A - Fixing plate for tensile material fixation, and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lightweight fixing plate using a string-like fiber-reinforced composite material as a raw material, and usable for fixation of a tensile material such as a PC steel or a ground anchor.SOLUTION: Many fiber-reinforced composite material pieces 4 formed by cutting, at a length within a fixed range in a length direction, a string-like fiber-reinforced composite material 3 molded by impregnating an adhesive synthetic resin into a string-like fiber-reinforced bundle 1, are piled up, and in company with heating, pressurized in a thickness direction and molded tabularly, and then an insertion hole 7a penetrating in the thickness direction is formed on a center part of a plane.SELECTED DRAWING: Figure 1

Description

  The present invention uses a fiber-reinforced composite material piece made of a string-like fiber-reinforced composite material, and a fixing plate for fixing a tensile material that can be used for fixing a fixing side end of a tensile material (tension material). It relates to the manufacturing method.

  Fiber reinforced composites (fiber reinforced plastics) are being used as tension bearing materials to replace PC steel because of their high tensile strength while carbon fibers and other reinforcing fibers themselves are lightweight (Patent Literature) 1-3). Patent Documents 1 to 3 all show examples in which a fiber-reinforced composite material is used as a tension material (tensile material).

  The fiber reinforced composite material may be used for the purpose of imparting tensile resistance to the surface of the concrete member (see Patent Document 4).

JP 2006-97462 A (paragraphs 0035 to 0046, FIG. 1) JP 2010-159562 A (paragraph 0010, FIG. 3, FIG. 5) Japanese Patent Laying-Open No. 2011-236688 (paragraph 0012, FIG. 1) JP 2011-99206 A (paragraphs 0002 to 0004, 0015 to 0019, FIGS. 2 and 3)

  As mentioned above, the fiber-reinforced composite material is characterized by having high tensile strength in the fiber direction, so the products of any of the above examples using this material are limited to applications that make use of the original characteristics of the material. For example, there is no use example as a plate used for the purpose of bearing a compressive force for fixing an end portion of a tensile material such as a PC steel material or a ground anchor.

  The present invention proposes a fixing plate for fixing a tensile material using a fiber reinforced composite material, which bears a compressive force in the thickness direction, and a method of manufacturing the same.

  The fixing plate for fixing a tensile material according to the first aspect of the present invention is a length within a certain range from a string-like fiber reinforced composite material formed by impregnating a string-like reinforcing fiber bundle with an adhesive synthetic resin. It is a constituent requirement that a large number of fiber-reinforced composite material pieces 4 formed in a linear shape with a shape are formed into a plate shape, and an insertion hole penetrating in the thickness direction is formed at the center portion on the plane.

  The term “adhesive synthetic resin” refers to a synthetic resin that exhibits adhesiveness when heated and melted, fluidized, or softened. Synthetic resins are thermoplastic or thermosetting as long as they can be melted when heated, become fluid, or soften and become tacky. It doesn't matter. However, the synthetic resin must be molten, fluid, or softened when the reinforcing fiber bundle 1 is impregnated.

  The performance of “adhesiveness of the synthetic resin” is that the string-like fiber reinforced composite material 3 formed by impregnating the reinforcing fiber bundle 1 with the synthetic resin is cut into an appropriate length to form a fiber reinforced composite material piece 4. It is made use after. That is, when the fiber reinforced composite material pieces 4 are stacked in the lower mold 8 and the upper mold 9 for forming the fixing plate 7 and pressed while being heated (Claim 4), the fiber reinforcement Adhesion exhibits a function for integration by bonding the composite pieces 4 and 4 together.

  A large number of fiber-reinforced composite material pieces 4 formed by cutting the string-like fiber-reinforced composite material 3 can form a plate-like space having a hole in the center when they are combined with each other, and in the opposite direction. It is filled between the lower mold 8 and the upper mold 9 that can move relative to each other (claim 4).

  While the fiber reinforced composite piece 4 is filled between the lower mold 8 and the upper mold 9, the synthetic resin can be melted, fluidized, or softened and heated to a temperature that can be tacky. The lower mold 8 and the upper mold 9 are basically pressed into the center of the lower mold 8 and the upper mold 9 by pressing the lower mold 8 and the upper mold 9 with a pressure that can reduce the volume of the total fiber-reinforced composite piece. This is completed as a fixing plate 7 for fixing a tensile material (hereinafter referred to as a fixing plate 7) having an insertion hole 7a in the portion and capable of bearing a compressive force in the thickness direction (Claim 4).

  The “length within a certain range” at which the fiber reinforced composite material 3 is cut refers to a single piece of the fiber reinforced composite material piece 4 after cutting, as shown in FIG. This length is determined by the shape of the lower mold 8 and the upper mold 9 and the dimensions of the inner periphery. In addition, when the fiber reinforced composite material piece 4 can be softened and have adhesiveness when heated, the fiber reinforced composite material piece 4 is deformed by pressurization, and the synthetic resin has fluidity. That's fine. “Temperature that can have adhesiveness” refers to a temperature at which adhesiveness can be exhibited.

  The insertion hole 7a at the center of the plate-like body which is the plate-like fixing plate 7 is formed by drilling (perforation (cutting out)) after forming the plate-like body by heating and pressurizing the fiber reinforced composite material piece 4. (Claim 5). In that case, when the lower mold 8 and the upper mold 9 are combined with each other, it is not necessary to form a plate-shaped space having a hole in the center, and when combined with each other, a plate-shaped space can be formed. (Claim 5). In this case, after the plate-shaped body is formed by filling the fiber-reinforced composite material piece 4 between the lower mold 8 and the upper mold 9 and heating / pressurizing the fiber-reinforced composite material piece 4, the plate-shaped body is formed. The fixing plate 7 is manufactured by forming an insertion hole 7a at the center of the fixing plate 7 (claim 5). The means for forming the insertion hole 7a after the plate-like body is formed is not limited. “Plate-like body” means “plate (fixing plate)”, but is called “plate-like body” because it is in a state before completion as “fixing plate 7”.

  Also in this case, at the time of heating to the fiber reinforced composite material piece 4, the synthetic resin impregnated in the fiber reinforced composite material piece 4 can be melted, fluidized, or softened to a temperature at which it can have adhesiveness. The fiber reinforced composite piece 4 is heated. While the fiber reinforced composite material piece 4 between the lower die 8 and the upper die 9 is heated, it is pressed with a pressure that can reduce the volume of all the fiber reinforced composite material pieces. The body is molded. An insertion hole 7a is formed in the formed plate-like body by a drill, punching or other means.

  “Plate shape” that specifies the shape of the fixing plate 7 means that the front and back surfaces (upper and lower surfaces) are substantially or substantially flat plate shapes (flat plate shapes), and the outer shape is rectangular. It does not matter whether the shape is circular or polygonal. “Substantially flat” means that the front and back surfaces have a concave curved surface or a convex curved surface, and includes a completely flat surface. The “center portion on the plane” is the center portion when the fixing plate 7 is viewed in the thickness direction, and the “hole” is an insertion hole 7a for inserting a tensile material (tension material) such as PC steel material, The shape of the hole includes a circular shape and a polygonal shape. The “flat plate” in claim 5 refers to the plate-like fixing plate 7 before the insertion hole 7a is formed as described above, and the shape thereof is “plate (flat plate)”.

  The reinforcing fiber bundle 1 is a bundle of fibers formed by bundling thousands to millions of yarns of reinforcing fibers such as carbon fibers, glass fibers, and aramid fibers. The fiber reinforced composite material 3 is configured by impregnating the reinforced fiber bundle 1 with a fluid synthetic resin. Here, a sizing agent may be provided in the reinforcing fiber bundle 1 made of reinforcing fiber yarns in order to enhance the integrity between the reinforcing fiber yarns.

  It is considered that the degree of integration or the state of integration of a large number of fiber-reinforced composite pieces 4 and 4 due to the adhesiveness of the synthetic resin depends on the amount of synthetic resin impregnated into the reinforcing fiber bundle 1.

  In addition, when a partial concentrated load in the thickness direction or a distributed load is applied to the surface of the fixing plate 7 formed by integration with the assembly of a large number of fiber-reinforced composite pieces 4, that is, the upper surface in the use state, The lower surface (rear surface) which is the surface opposite to that portion is likely to be a weak point in strength, and it can be assumed that the surface may be damaged by a tensile force. In such a case, particularly by concentrating the fiber reinforced composite material pieces 4 on the back surface (lower surface) of the fixing plate 7, that is, by increasing the density of the fiber reinforced composite material pieces 4 on the back surface (lower surface) of the fixing plate 7, It is possible to reinforce the back surface (lower surface) of the fixing plate 7 against a concentrated load or the like.

  In this case, the density of the reinforcing fibers is increased by increasing the ratio of the reinforcing fibers in the back surface (lower surface) side of the fixing plate 7 formed from a large number of fiber reinforced composite material pieces 4, and the density of the synthetic resin is relatively increased. Therefore, the safety against damage to the back surface (lower surface) due to concentrated load received on the surface (upper surface) of the fixing plate 7 is improved.

  In the state where the synthetic resin occupies most of the rear surface (lower surface) side portion of the fixing plate 7 and the density of the fibers is low, the synthetic resin tends to flow due to concentrated load (pressure), and therefore the fixing plate 7 is easily deformed. it is conceivable that. On the other hand, since the fibers are densely present on the back surface side of the fixing plate 7, the fibers are bonded to each other, and the fibers that are resistance elements against the tensile force work to restrain the flow of the synthetic resin, so that the density of the fibers is low. In comparison with the case, it is considered that the flow of the synthetic resin is less likely to occur. As a result, the fixing plate 7 is less likely to be deformed, and the safety against damage to the back surface due to a concentrated load received on the surface of the fixing plate 7 is improved.

  In order to reinforce the back surface (lower surface (back surface)) on the side receiving the tensile force of the fixing plate 7 against a concentrated load or the like, the reinforcing fiber sheet 71 is attached to one surface in the thickness direction of the fixing plate 7. (Claims 3 and 6). One surface in the thickness direction of the fixing plate 7 indicates a back surface (lower surface) in a use state, which is a surface on the side receiving a tensile force with respect to a load in the thickness direction on the fixing plate 7 in principle. “Adhesion” means that the fixing plate 7 is integrated with the fixing plate 7 body by adhesion, compression, or adhesion (crimping) with compression and heat. As the reinforcing fiber sheet 71, a carbon fiber sheet, an aramid fiber sheet or the like is mainly used. In addition, the reinforcing fiber sheet 71 also includes a woven fabric, a knitted fabric, a non-woven fabric, or a composite of these and a synthetic resin. In this case, it is appropriate that the synthetic resin has adhesiveness similar to that of the fiber reinforced composite material 4.

  The fixing plate 7 is formed by pressurization accompanied by heating to the fiber reinforced composite material piece 4 formed by cutting the fiber reinforced composite material 3 impregnated with an adhesive synthetic resin (claims 2, 4). ), By placing the reinforcing fiber sheet 71 on at least one side of the fiber reinforced composite piece 4 to be the fixing plate 7 and pressurizing both at the same time when pressurizing the fiber reinforced composite piece 4, The reinforcing fiber sheet 71 is integrated with the main body of the fixing plate 7 by adhesion accompanied by compression, and the fixing plate 7 to which the reinforcing fiber sheet 71 is adhered is manufactured (Claim 6). 6. “With heating to a temperature at which the synthetic resin can be melted” in claims 4 and 5 means “pressurizing while continuing heating” and “stopping the heating operation after the heating temperature reaches a certain temperature” And pressurizing ". This is because after the heating temperature reaches a certain temperature, the temperature is maintained even if the heating is stopped, and “pressurization in a heated state” is realized.

  In this case, in the process of filling the fiber reinforced composite material piece 4 between the lower die 8 and the upper die 9 in the manufacturing method of claim 4 or claim 5, the fiber reinforced composite material piece 4 is placed on the lower die 8. The reinforcing fiber sheet 71 is disposed before the filling, or the reinforcing fiber sheet 71 is disposed on the fiber reinforced composite piece 4 filled on the lower mold 8, and the lower mold 8 and the upper mold 9 are pressed as they are. Thus, the fixing plate 7 in which the reinforcing fiber sheet 71 is adhered to at least one side in the thickness direction is manufactured (Claim 6).

  When the reinforcing fiber sheet 71 is attached to the fixing plate 7 (Claims 3 and 6), the reinforcing fiber sheet 71 serving as a resistance element against the tensile force bears the tensile force. Since the burden is reduced, the stability of the fixing plate 7 against the concentrated load is improved, and the possibility that the fixing plate 7 is damaged by receiving a load in the thickness direction is reduced.

  Since the fiber-reinforced composite material 3 is formed by impregnating the reinforcing fiber bundle 1 or the like with the synthetic resin as shown in FIG. 1 while maintaining the shape of the string-like reinforcing fiber bundle 1 as the original material (Claim 4). When the reinforcing fiber bundle 1 is impregnated with the synthetic resin, for example, the reinforcing fiber bundle 1 has a linearly continuous shape in the axial direction or a spirally twisted shape. As shown in FIG. 1, after impregnating the reinforcing fiber bundle 1 with the synthetic resin, the synthetic resin is dried and cured, and then the fiber reinforced composite material 3 is cut into fiber reinforced composite material pieces 4 having a length within a certain range. Then, the fiber-reinforced composite material piece 4 generated by this cutting is filled between the lower mold 8 and the upper mold 9 as shown in FIG. The “length within a certain range” means a size that allows the single fiber-reinforced composite material piece 4 to be accommodated between the lower mold 8 and the upper mold 9 as described above.

  The shapes of the lower die 8 and the upper die 9 may be any shape as long as the space formed between the lower die 8 and the upper die 9 becomes a plate shape such as a disk shape or a polygonal plate shape. The shape of the space formed between the lower mold 8 and the upper mold 9 is the shape of the fixing plate 7 that is filled in this space and compressed. The fixing plate 7 may have a uniform thickness as a whole, or may vary in thickness as a whole or in part, depending on the part to be used. “Plate shape” means a shape including a plate (flat plate) whose upper and lower surfaces (front and back surfaces) are completely flat and a three-dimensional shape close to a plate of this shape.

  When the fixing plate 7 having the insertion hole 7a is formed by heating and pressurization after filling the fiber reinforced composite material piece 4 between the lower mold 8 and the upper mold 9 (Claim 4), the lower mold 8 and the upper mold 9 As shown in FIG. 3- (a), an insertion hole 7a is formed in the central portion on the plane of the fixing plate 7 formed by pressing in the thickness direction. The convex part 81 shown in FIG. 2- (c) which becomes an intermediate | middle type | mold for doing is arrange | positioned or formed. The convex portion 81 for forming the insertion hole 7 a in the fixing plate 7 may be formed on the upper plate 9 a of the upper die 9 facing the bottom plate 8 a of the lower die 8. The insertion hole 7a of the fixing plate 7 is basically formed at one place, but a plurality of insertion holes 7a may be formed at a plurality of places at the center on the plane.

  When a plate-shaped body is formed by heating and pressurization after filling the fiber-reinforced composite material piece 4 between the lower mold 8 and the upper mold 9, and then an insertion hole 7a is formed (pierced) in the plate-shaped body ( According to the fifth aspect of the present invention, it is not necessary for the convex portion 81 to be disposed or formed between the lower mold 8 and the upper mold 9. When the lower mold 8 and the upper mold 9 are combined with each other, a plate-like space is provided. (Claim 5). The “plate-like body” referred to here does not need to be a plate whose upper and lower surfaces are completely flat as described above, and refers to a plate (flat plate) before the insertion hole 7a is formed.

  In FIG. 3, a columnar convex portion 81, which is separate from the lower die 8 and the upper die 9, is installed on the bottom plate 8 a of the lower die 8, and an insertion hole 9 b into which the convex portion 81 can be inserted is formed in the upper die 9. Although an example of the case is shown, even when the convex portion 81 is formed on the bottom surface of the lower mold 8, the upper die 9 has an insertion hole 9 b through which the convex portion 81 can be inserted or a concave portion into which the convex portion 81 can be fitted. It is formed. When the thickness of the fixing plate 7 to be manufactured is set small, the adjusting plate 10 shown in FIG. 2E is used to reduce the filling amount of the fiber reinforced composite material piece 4 on the bottom surface of the lower mold 8. Is placed. The adjustment plate 10 is also formed with an insertion hole 10a through which the convex portion 81 can be inserted.

  The “plate-shaped space having a hole in the central portion” in claim 4 means that the lower mold 8, the upper mold 9, and the convex portion 81 are formed by the lower mold 8, the convex mold 81, and the convex mold 81. It is a space excluding the portion 81, and the “plate-like space” is a space between the lower mold 8 and the upper mold 9 and sandwiched between both molds 8, 9, The “space having a hole in the portion” refers to a space formed around the convex portion 81. A large number of fiber reinforced composite material pieces 4 are accommodated in a “plate-like space having a hole in the central portion” formed by the lower die 8, the upper die 9 and the convex portion 81, and compressed while being heated. The fixing plate 7 having the shape of the space is formed.

  After the fiber reinforced composite piece 4 is filled between the lower mold 8 and the upper mold 9, the synthetic resin can be heated to a temperature at which the synthetic resin can be melted, fluidized, or softened to have adhesiveness. Accordingly, the lower mold 8 and the upper mold 9 are compressed in a direction facing each other by being pressurized with a pressure that can reduce the volume of all the fiber-reinforced composite pieces in the lower mold 8 and the upper mold 9. The fixing plate 7 is manufactured (claim 4). In addition, the volume of all the fiber reinforced composite material pieces in the lower die 8 and the upper die 9 is such that the fiber reinforced composite material pieces 4 before pressurization filled in the lower die 8 and the upper die 9 are overlapped with each other. This means an apparent volume having a space between the reinforced composite pieces 4, and when the fixing plate 7 is formed, the fiber reinforced composite pieces 4 are pressed while being heated, so that the volume of the reinforced composite pieces 4 is reduced. May not decrease.

  In the step of pressurizing the fiber reinforced composite material piece 4, the fiber reinforced composite material constituting the single fixing plate 7 is formed by compacting the fiber reinforced composite material pieces 4 laminated in the thickness direction of the fixing plate 7 in the thickness direction. In order to increase the density of the material pieces 4 and increase the compressive strength and tensile strength of the fixing plate 7, heating of the fiber reinforced composite material pieces 4 or heating and pressurization may be repeated several times. ). In this case, the density unevenness in the layer of the fiber-reinforced composite piece 4 that is consolidated in the thickness direction of the fixing plate 7 and laminated is also reduced.

  “The synthetic resin can be melted, fluidized, or softened to have adhesiveness” means that the synthetic resin is in a liquid state and impregnated in the reinforcing fiber bundle 1 or the like. Is in a state where it softens and exhibits adhesiveness, preferably it has fluidity and can be deformed. “Pressure at which the volume of the entire fiber-reinforced composite piece can be reduced” means that the fiber-reinforced composite piece 4 is not restored by elasticity (plasticized) after the pressure is removed or before being pressed. The pressure is such that the volume when the piece 4 does not retain its original shape and the whole fiber-reinforced composite piece is collected without gaps, for example, can be reduced after pressurization. “Can be reduced” means that the volume of all fiber reinforced composite pieces does not necessarily decrease after pressing.

  As a result of pressurization and heating in the lower mold 8 and the upper mold 9, the fused fiber reinforced composite piece 4 is mixed with a large amount of reinforcing fibers as the raw material of the fiber reinforced composite material 3 in the synthetic resin as the other raw material. In this state, the reinforcing fibers are cured in a plurality of directions in the in-plane direction of the fixing plate 7 and densely arranged in the thickness direction. Since the pressurization at this time is a direction in which the lower mold 8 and the upper mold 9 face each other, the direction of the fibers is mainly directed in a direction perpendicular to the thickness direction (in-plane direction of the fixing plate 7). “The direction in which the lower mold 8 and the upper mold 9 face each other” is the thickness direction of the fixing plate 7.

  Here, as a result of heating and pressurizing a large number of fiber reinforced composite material pieces 4, the thickness of the test piece of the fixing plate 7 having a hole (insertion hole 7 a) at the center and molded to a fixed size is changed. Conditions (CASE) when compressive force is applied in the vertical direction are shown in FIGS. 7- (a) to (d), and the relationship between load and displacement for each condition is shown in FIGS. 8- (a) to (d). Detailed conditions at the time of pressurization are shown in Table 1 below.

  As shown in FIG. 6- (a), which shows the state of a loading test in which a compressive force is applied to the test body (fixing plate 7), the loading test assumes that the test body is actually used as the fixing plate 7, and PC steel It was performed in a form to reproduce the state of receiving the end of a tensile material such as a ground anchor. FIG. 6B shows the state of the back surface (back surface) of the test body in which a strain gauge 16 for measuring the load and strain acting on the test body (fixing plate 7) is connected around the insertion hole 7a. Shows a state in which the reinforcing fiber sheet 71 is attached to one side of the back surface (lower surface) or the front surface (upper surface) of the test body in use. (D) shows the base plate 14 and (e) shows the nut 15.

  Here, the reinforcing fiber sheet 71 is impregnated with an adhesive synthetic resin to enhance the integrity of the test body (fixing plate 7) with the main body. In this case, the reinforcing fiber sheet 71 is heated and pressed together with the fiber reinforced composite material piece 4 in the manner shown in FIGS. 4- (a) and (b), whereby one side of the formed fixing plate 7 (test body). Affixed to. The thickness of the reinforcing fiber sheet 71 used here was about 1.1 mm when impregnated with synthetic resin, but it was compressed to 0.59 mm (about 54%) by being heated and pressurized. ing.

  In FIG. 6- (a), a test body (on a base plate 14 having an opening through which a tensile material is inserted, which is placed on a loading table 18 as a reaction force table that receives a reaction force of the pressurizing device 17. Assuming the case where the fixing plate 7) is placed and the tensile material is fixed to the nut, a nut 15 is arranged on the test body, and a pressurizing device 17 is installed on the nut 15 to pressurize with the nut 15. A load meter 19 is interposed between the devices 17. The base plate 14 is a base material that directly receives the fixing plate 7 or a receiving material that assumes a concrete structure. The test body is in a state of receiving a compressive force from the nut 15 placed around the insertion hole on the upper surface and a reaction force from the base plate 14 supported on the peripheral portion of the lower surface.

  The description and results of each condition are shown in Table 1 below. A plurality of samples are prepared as test specimens for each condition, and average values are described for the maximum load and maximum strain as a result. The dimensions of the test body are about 200 mm long × 200 mm wide × 23 mm thick.

  CASE 4 in Table 1 is from a general structural steel (SS400) used as a fixing plate (anchor plate) for fixing the end of a tensile material such as a ground anchor to be compared with the fixing plate 7 of the present invention. The pressure conditions and results of the molded perforated fixing plate (plate) are shown. The loading test of the fixing plate 7 of the present invention was carried out for the purpose of comparison with the result of CASE 4 (fixing plate).

  Carbon fiber is used as the reinforcing fiber to be the basis of the fiber reinforced composite material 3 constituting the CASE 1-3 specimens (fixing plate 7), and an epoxy resin (thermoplastic epoxy resin) is used as the synthetic resin (adhesive). Is used. The CASE 1 to 3 specimens are 200 mm in length and about 23 mm in thickness, and have an insertion hole 7 a with a diameter of 46 mm that penetrates in the thickness direction at the center on the plane, and the mass is 1.35 kg. is there.

  The fixing plate as a test body is assumed to be a plate (steel plate) having an ability to support a tensile material having a tensile strength of about 261 kN (yield point load: about 222 kN). The “opposite side” in Table 1 for explaining the nut size refers to the distance d between two opposing faces of the hexagon nut, as shown in FIG. The dimensions of the CASE4 (steel) specimen (fixing plate) are almost the same as those of the CASE1 to CASE3 specimens, and the mass is 7.5 kg.

  In CASE 1 and CASE 2, for the purpose of confirming the presence or absence of the effect when the reinforcing fiber sheet 71 as a tensile resistance material is attached to one side of the test body, the reinforcing fiber sheet 71 is respectively connected to the base plate 14 (lower surface) side of the test body, It is stuck to the nut 15 (upper surface) side of the test body. In Table 1, the reinforcing fiber sheet 71 is abbreviated as a sheet. The strain gauge 16 is connected to the bottom surface of the test body as described above. In the test, a carbon fiber sheet having a thickness of 0.59 mm is used as the reinforcing fiber sheet 71.

  From the comparison of the results of CASE 1 and CASE 2 (FIGS. 8- (a) and (b)), in CASE 1, the increase in strain accompanying the increase in load is flat and the deformation property is stable, whereas in CASE 2, the distortion is stable. It can be seen that although there is fluctuation and the deformation is not stable, the distortion remains on average about 1/5 of CASE1. In addition, the direction of the large number of fiber reinforced composite material pieces 4 constituting the test body is not necessarily uniformly distributed in the radial direction, and varies from sample to sample. Also, variations are likely to occur. If CASE1 and CASE2 are seen in comparison with CASE3 to which the reinforcing fiber sheet 71 is not adhered, the reinforcing fiber sheet 71 is different in CASE1 and CASE2 but the reinforcing fiber sheet 71 is the fiber-reinforced composite material. It is considered that there is an effect of suppressing variation in distortion caused by variation in the pieces 4.

  CASE1 and CASE2 do not show a clear difference in the maximum load, but in CASE1 in which the reinforcing fiber sheet 71 is adhered to the opposite side of the loading surface, the deformation property is more stable than in CASE2, the reinforcing fiber sheet 71 is By sticking on the tensile surface of the test body, it is thought that there exists a function which stabilizes the deformation | transformation property of a test body. In contrast to CASE1 and CASE2, although there is no clear difference in the maximum load, the maximum load of CASE1 with the reinforcing fiber sheet 71 adhered to the tensile surface of the specimen is about 8% from the maximum load of CASE2 of about 120 kN. Since the degree is large, it can be said that the reinforcing fiber sheet 71 also exhibits a function as a tensile resistance material.

  When a plate-like (flat plate) specimen is supported around the lower surface (back surface) side and receives a concentrated load from the upper surface (front surface) side, the lower surface (back surface) side bears the tensile force, and the upper surface ( From the relationship that the (front surface) side bears the compressive force, the “tensile surface” refers to the lower surface that is the surface opposite to the loading surface on the specimen. Since the reinforcing fiber sheet 71 is a tensile resistance material, it can be said that it is mechanically reasonable that the specimen is attached to the lower surface (back surface) side where the tensile force is borne.

  The difference between CASE 1 and CASE 2 and CASE 3 is that the reinforcing fiber sheet 71 is not attached to the latter (CASE 3) and that the size (opposite side) of the nut 15 is large. The opposite side 72 mm of the nut 15 of CASE 3 is CASE 1 2 of the nut 15 is about 1.3 times larger than the opposite side 55 mm. Mainly due to this difference, CASE 3 achieves a strength of about 200 kN corresponding to 1.53 times the strength (maximum load) of CASE 1 and 1.67 times the strength of CASE 2. This value is about 0.87 times the strength of CASE 4 when the same nut 15 as CASE 1 and 2 is used.

  Considering that the difference in the presence or absence of sticking of the reinforcing fiber sheet 71 does not appear in the clear or extreme difference in strength of the specimen as described above, the size of the opposite side of the nut 15 increases the strength of CASE3. It can be said that there is a high possibility that In CASE3, because the opposite side of the nut 15 is larger than that in CASE1 and 2, the area of the test specimen that receives the load increases, and as a result of the compressive load being dispersed and acting, the strength is increased compared to CASE1 and 2. It is done.

  Although CASE3 (composite piece) and CASE4 (steel) have a difference in the dimensions of the nut 15, the maximum load of CASE3 has achieved about 200 kN, which is 0.87 times the maximum load of CASE4. It can be said that the combination of the test body and the nut 15 can exert the compressive force bearing ability comparable to the case of CASE4. In particular, the mass of the fixing plate 7 of CASE 3 is 1.35 kg, whereas the mass of the steel material of CASE 4 is 7.5 kg. Therefore, if the mass is compared, the fixing plate 7 of CASE 3 is 1.35 / 7.5. Furthermore, it can be said that it exhibits a compressive strength not inferior to that of steel, although it is about 18% of the mass of a fixing plate using CASE 4 steel. Therefore, it can be said that the fixing plate 7 of CASE 3 has an effect of significantly improving handling workability in comparison with the steel material while exhibiting a role in place of the fixing plate of the steel material.

  From the above comparison with the steel material (plate) of the same size, the fixing plate formed by assembling and integrating a large number of fiber-reinforced composite pieces has a mass smaller than 1/5 of the steel material, and the compression strength of the steel material. The ability to bear compressive force comparable to that of the same level can be demonstrated. As a result, while exhibiting the role of replacing the steel fixing plate, it has the effect of significantly improving the handling workability in comparison with the steel material. Therefore, the use as a compressive force bearing material replacing the steel material (plate) is established. be able to. Moreover, there is no worry of rusting like steel materials.

A step of immersing the reinforcing fiber bundle wound in the drum in a synthetic resin solution, a step of drying the reinforcing fiber bundle impregnated with the synthetic resin, and a fiber obtained by cutting the dried reinforcing fiber bundle in the length direction It is the schematic which showed the process of forming a reinforced composite material piece continuously. (A) is a perspective view showing a state in which a large number of fiber-reinforced composite material pieces shown in FIG. 1 are randomly stacked, and (b) is for forming a fixing plate using the fiber-reinforced composite material pieces of (a). The perspective view which showed the lower mold | type, (c) The perspective view which showed the convex part arrange | positioned on a lower mold | type, (d) The perspective view which showed the bottom face of the upper mold | type arrange | positioned facing a lower mold | type. (E) is the perspective view which showed the adjustment board arrange | positioned between a lower mold | type and an upper mold | type in order to adjust the thickness of a fixing plate. (A) is the perspective view which showed a mode that the convex part was arrange | positioned on a lower mold | type, (b) shows a mode that the fiber reinforced composite material piece shown to FIG. 2- (a) was piled up and filled inside the lower mold | type. (C) is a perspective view showing a state in which the upper die is dropped onto the lower die, and the lower die and the upper die are heated and the upper die is pressurized in a direction opposite to the lower die, (d). FIG. 6 is a perspective view showing a fixing plate formed as a result of heating and pressing in (c). The perspective view which showed a mode that the reinforcement fiber sheet was arrange | positioned on the bottom plate of a lower mold | type, when producing the test body (fixing board) to which the reinforcement fiber sheet shown in FIG.6- (c) was affixed, (b) FIG. 3 is a perspective view showing a state in which a fiber reinforced composite material piece is filled on the reinforcing fiber sheet of FIG. (A)-(f) is the perspective view which showed the work procedure in the case of repeating heating of a fiber reinforced composite material piece in multiple times at the process of pressurizing a fiber reinforced composite material piece. (A) is the perspective view which showed the condition of the loading test, (b) is the perspective view which showed a mode that the strain gauge was connected to the test body, (c) is the test body (the reinforcing fiber sheet stuck on one side) ( (F) is a perspective view showing a base plate used in the loading test, and (e) is a perspective view showing a nut used in the loading test. (A)-(d) is the elevation which showed each loading condition of CASE1-CASE4 of Table 1. FIG. (A)-(d) is the graph which showed the relationship between the distortion which arose in the test body at the time of each loading of CASE1-CASE4 of Table 1, and a load.

  FIG. 1 shows a state in which a reinforcing fiber bundle 1 made of a bundle of reinforcing fibers such as carbon fiber and glass fiber is wound around a drum 20 and immersed in a synthetic resin solution tank 21 filled with an adhesive synthetic resin solution. After the reinforcing fiber bundle 1 and the core material 2 are impregnated with synthetic resin to form the string-like fiber reinforced composite material 3, the fiber reinforced composite material 3 is passed through the drying box 22 as it is to dry the synthetic resin. An example of an operation procedure until the fiber-reinforced composite material piece 4 is formed by cutting the fiber-reinforced composite material 3 in the cutting machine 23 is shown.

  FIG. 1 is an example of the procedure, and it is not necessary to impregnate the reinforcing fiber bundle 1 with the synthetic resin in a state in which the reinforcing fiber bundle 1 is wound around the drum 20, and impregnate the synthetic resin in a linear state when the reinforcing fiber bundle 1 is generated. For example, the state of the reinforcing fiber bundle 1 when the reinforcing fiber bundle 1 is impregnated with the synthetic resin is not limited. Other work steps need not be as shown in FIG.

  One reinforcing fiber bundle 1 is formed by bundling several thousand to several million yarns of reinforcing fibers as described above. The diameter of the reinforcing fiber bundle 1 is about 1 to 100 mm, and the length of the reinforcing fiber bundle 1 is about several tens of centimeters to several tens of meters.

  The reinforcing fiber bundle 1 is formed into a fiber reinforced composite material 3 by impregnation with a synthetic resin, and then cut into a fiber reinforced composite material piece 4 by being cut at a cutting surface in a direction intersecting the length direction. Since the fiber-reinforced composite piece 4 is compressed in the lower mold 8 and the upper mold 9, the cross-sectional shape of the reinforcing fiber bundle 1 is not limited, and it is not always necessary to have a circular shape or a shape close to a regular polygon shape.

  The fiber reinforced composite material 3 is formed by impregnating the reinforcing fiber bundle 1 with a synthetic resin having fluidity including a molten state. Examples of the adhesive synthetic resin include polypropylene, polyethylene, polystyrene, ABS resin, acrylic resin, polyester resin, polyamide resin, and epoxy resin.

  3- (a) to (d) cut the dried string-like fiber reinforced composite material 3 into a certain length in the length direction to form a large number of fiber reinforced composite material pieces (chips) 4; The fiber-reinforced composite pieces 4 are filled between the lower mold 8 and the upper mold 9 that can form a plate-like space when they are combined with each other, and are heated and pressed to form a plate-like thickness. The procedure until the fixing plate 7 that can bear the compressive force in the direction will be shown.

  The fiber reinforced composite material piece 4 is cut as a single piece into a size (length) that can be filled between the lower mold 8 and the upper mold 9. Since the string-like fiber reinforced composite material 3 is formed in a cross-sectional shape similar to these, for example, circular, elliptical, polygonal, or flat shape, the fiber-reinforced composite piece 4 has these cross-sectional shapes. It is formed into a three-dimensional shape. The cut surface has a direction orthogonal to the axial direction and other directions. Stability (hardness of rolling) of the fiber reinforced composite piece 4 when filled between the lower mold 8 and the upper mold 9 and the resulting fiber reinforced composite piece 4 in the space between the lower mold 8 and the upper mold 9 From the viewpoint of dispersibility, the fiber reinforced composite piece 4 is preferably a strip having a flat cross-sectional shape.

  The lower mold 8 is formed in a box shape having a bottom plate 8a and a side wall 8b standing from its periphery as shown in FIG. 2 (b) in order to constrain the fiber reinforced composite material piece 4 filled therein in a filled state. Then, a convex portion 81 that forms the insertion hole 7a of the fixing plate 7 is placed on or formed on the bottom plate 8a. The upper die 9 has a shape having at least an upper plate 9a facing the bottom plate 8a of the lower die 8, and an insertion hole 9b through which the convex portion 81 is inserted when the lower die 8 and the upper die 9 are pressed, A recessed portion to be fitted is formed. The upper plate 9a has a shape and a flat area that can be accommodated or inscribed inside the side wall 8b that circulates the lower mold 8.

  The heating temperature of the fiber-reinforced composite piece 4 when the lower mold 8 and the upper mold 9 are pressed in the opposite direction is a temperature at which the synthetic resin can be melted, fluidized, or softened to have adhesiveness. Yes, it is the temperature at which the fiber-reinforced composite piece 4 itself can be deformed. At the time of pressurization, a pressure of a magnitude that can decrease the volume of all the fiber-reinforced composite pieces before pressurization existing in at least the lower mold 8 and the upper mold 9 is given.

  The lower mold 8 and the upper mold 9 are pressurized while being heated or heated after being heated from the upper and lower pressure plates 11 and 12 sandwiching both in the opposing direction as shown in FIG. Since the fiber reinforced composite material piece 4 is indirectly heated from the pressure plates 11 and 12 through the lower mold 8 and the upper mold 9, a large number of fiber reinforced composite material pieces 4 are integrated with the upper and lower pressure plates 11 and 12. As a temperature at which the adhesive synthetic resin that functions to melt can be melted, fluidized, or softened to have tackiness, for example, a temperature higher than the melting point or softening point of the synthetic resin or the glass transition point is given. . Specifically, the melting point of the synthetic resin is about 100 to 150 ° C., but in the example shown in Table 1 using an epoxy resin as the synthetic resin, the melting point (including the softening point and the glass transition point) of the synthetic resin is 150. It is heated to about 240-280 ° C., which is about twice as high as that of ° C.

  It is sufficient that at least one of the upper and lower pressure plates 11 and 12 that pressurize the lower mold 8 and the upper mold 9 in a direction opposite to each other is in a state where the lower mold 8 and the upper mold 9 are opposed to each other. The pressure plates 11 and 12 may move together. In any form, the fiber-reinforced composite piece 4 existing between the lower mold 8 and the upper mold 9 is compressed in the pressing direction. Heaters 11a and 12a and temperature sensors 11b and 12b for heating the lower mold 8 and the upper mold 9 are arranged inside the pressure plates 11 and 12 by heating the pressure plates 11 and 12 themselves.

  The pressurization of the lower mold 8 and the upper mold 9 by the pressurizing plates 11 and 12 is caused by a number of fiber-reinforced composites while the pressurizing plates 11 and 12 are raised to the set temperature (240 to 280 ° C.) or after reaching the set temperature. The pressure required for the target thickness of the fixing plate 7 manufactured from the material piece 4 is held (applied) for a certain time. The examples in Table 1 show the results when a pressure of 4 MPa is applied for about 30 minutes in the direction facing the pressure plates 11 and 12 after the pressure plates 11 and 12 reach the set temperature. The pressing time varies depending on the amount (mass) of the fiber reinforced composite piece 4 to be designed and the thickness of the fixing plate 7.

  Each fiber-reinforced composite material piece 4 is not in a state of being present alone by heating and pressurization, and the reinforcing fiber bundle 1 constituting each fiber-reinforced composite material piece 4 or the reinforcing fiber that is a component thereof is each fiber. As a result of being bonded to each other with an adhesive synthetic resin constituting the reinforced composite piece 4 and being consolidated while the reinforcing fiber bundles cross each other, the fixing plate 7 as a molded product shown in FIG. become.

  When the reinforcing fiber sheet 71 is attached to one side of the fixing plate 7 as shown in FIG. 6- (c), for example, as shown in FIGS. A reinforcing fiber sheet 71 is laid on the bottom plate 8a before the reinforcing composite piece 4 is charged. The reinforcing fiber sheet 71 may be placed on the fiber reinforced composite piece 4 filled on the bottom plate 8 a after the fiber reinforced composite piece 4 is put into the lower mold 8. When the reinforcing fiber sheet 7 is stuck on both surfaces of the fixing plate 7, the reinforcing fiber sheet 71 is laid on the bottom plate 8 a before the fiber reinforced composite material piece 4 is put into the lower mold 8. After the fiber reinforced composite piece 4 is put on 71, the fiber reinforced composite piece 4 is placed on the filled fiber reinforced composite piece 4 so as to be covered.

  5- (a)-(f) shows the work procedure in the case of repeating the heating of the fiber reinforced composite material piece 4 a plurality of times in the process of pressurizing the fiber reinforced composite material piece 4. FIG. The fiber reinforced composite material piece 4 is filled around a columnar convex portion 81 disposed at the center on the bottom plate 8a of the lower mold 8 as shown in FIGS. In the example shown in FIG. 5, as shown in FIG. 3B, the fiber reinforced composite material piece 4 is densely filled in the upper die 8 (upper), and the upper die 9 is placed on the lower die 8 as it is. Without reducing the volume of the fiber reinforced composite piece 4 in the lower mold 8 by heating the fiber reinforced composite piece 4 in the lower mold 8 without pressurizing the fiber reinforced composite piece 4 Is shown.

  When the fiber reinforced composite piece 4 is heated in the lower mold 8, the upper mold 9 is placed on the lower mold 8, and the fiber reinforced composite piece 4 is sandwiched between both molds 8, 9. While the upper mold 9 is heated, the pressure may be applied in the opposite direction.

  In the case of the example shown in FIG. 5, the lower die 8 filled with the fiber reinforced composite piece 4 is inserted into the heating / pressurizing device 13 without the upper die 9 being placed as shown in FIG. And heated for a certain time. By heating the fiber reinforced composite piece 4 filled in the lower mold 8, the synthetic resin is melted and the entire volume of the fiber reinforced composite piece 4 in the lower mold 8 is reduced. Thereafter, the lower mold 8 is taken out from the heating / pressurizing device 13 as shown in FIG. 5B, and the fiber-reinforced composite piece 4 is added into the lower mold 8 as shown in FIG.

  Thereafter, the lower mold 8 to which the fiber reinforced composite piece 4 has been added is again inserted into the heating / pressurizing device 13 and heated for a predetermined time. The heating and addition of the fiber reinforced composite piece 4 may be repeated three or more times. In the drawing, the heating / pressurizing device 13 serves as a heating device and a pressurizing device, but the heating device and the pressurizing device may be different.

  The total amount of the fiber reinforced composite material pieces 4 put into the lower mold 8 is determined in advance from the mass of the fixing plate 7 to be finally formed, for example, 1350 g described above. Heating and addition are repeated until the piece of material 4 has entered the lower mold 8.

  After a predetermined amount of the fiber-reinforced composite material piece 4 has been put into the lower mold 8, the upper mold 9 is placed on the lower mold 8 as shown in FIG. Is inserted into the heating / pressurizing device 13, and the lower die 8 and the upper die 9 are pressurized in the opposite direction as shown in FIG. The pressurization is continuously applied to the pressurization plates 11 and 12 after the pressurization plates 11 and 12 reach a preset temperature, for example, about 240 ° C. as described above. In the example of Table 1, as described above, a pressure of 4 MPa is applied to the pressure plates 10 and 11 for about 30 minutes. Further, as described above, the pressure plates 11 and 12 may be pressurized while being raised to a preset temperature.

  After pressurizing the pressure plates 11 and 12, the lower mold 8 and the upper mold 9 are cooled by feeding cold air from the cooling device 24 into the heating / pressurizer 13, for example, as shown in FIG. The fixing plate 7 that is a molded product of the composite material piece 4 is cooled.

  The fixing plate 7 may be cooled with the upper die 9 removed or with the fixing plate 7 detached from the lower die 8. After the fixing plate 7 which is a molded product is cooled, the fixing plate 7 is completed as shown in FIG.

Here, among the examples in Table 1 used for the loading test shown in FIGS. 5A and 7, the fiber reinforcement required for the production of the 200 mm × 200 mm × 23 mm test body (fixing plate 7) of CASE 1 to 3 is used. The amount of the composite piece 4 is calculated. If the average mass per unit volume of the fiber reinforced composite piece 4 is 0.3 g / cm ³ , the mass of the test body (plate-like body 7) is 1350 g as described above. The volume of all fiber-reinforced composite pieces before pressing is 1350 / 0.3 = 4500 cm ³ . Since the volume of the specimen after pressurization is (20 cm × 20 cm−π · 2.3 ² ) × 2.3 cm = 881.78 cm ³ , the volume of the total fiber reinforced composite piece is about 1 as a result of pressurization. / 5 (about 19 to several 20%).

  Since the fixing plate 7 is used as a member replacing the plate made of a steel material at a portion bearing a compressive force in the thickness direction, such as a fixing portion on the tension side of a PC steel material to be described later, the form plate mainly has a central portion. It is formed in the same shape as a base plate having an insertion hole, an anchor plate or the like. In this relation, the fixing plate 7 is basically formed in a flat plate shape having a uniform thickness on both the upper surface and the lower surface. For example, the lower surface (back surface) which is one surface in the thickness direction is installed. Depending on the shape of the surface, the surface is formed into a flat surface, a curved surface, or a polygonal shape, and the upper surface (surface) as the other surface is a free surface. The other surface may be formed in a shape having a plurality of steps.

  An insertion hole 7a through which a tensile material (tension material) such as a PC steel material, an anchor (including a ground anchor), a reinforcing bar, or the like that applies a compressive force in the thickness direction to the fixing plate 7 is shown in FIG. Thus, although one is mainly formed in the central portion, a plurality of insertion holes 7a may be formed in a dispersed manner. As described above, the insertion hole 7a is formed, for example, by arranging the convex portion 81 on the bottom plate 8a of the lower mold 8 or by forming the convex portion 81 as shown in FIG. 81 may be formed on the upper plate 9a of the upper mold 9 toward the lower mold 8 side. The convex part 81 is arranged, or an insertion hole 9b through which the convex part 81 is inserted or a concave part to be fitted is formed in a plate on the opposite side to the side on which the convex part 81 is formed.

1 ... Reinforced fiber bundle,
3 ... Fiber reinforced composite material, 4 ... Fiber reinforced composite material piece,
7: Fixing plate, 7a: Insertion hole, 71: Reinforcing fiber sheet,
8: Lower mold, 8a: Bottom plate, 8b: Side wall, 81: Projection,
9: Upper mold, 9a: Upper plate, 9b: Insertion hole,
10: Adjustment plate, 10a: Insertion hole,
11 ... Pressure plate (top), 11a ... Heater, 11b ... Temperature sensor,
12 ... Pressure plate (bottom), 12a ... Heater, 12b ... Temperature sensor,
13 …… Heating / pressurizing device,
14 …… Base plate, 15 …… Nut,
16 ... Strain gauge, 17 ... Pressure device, 18 ... Loading platform, 19 ... Load meter,
20 ... Drum, 21 ... Synthetic resin solution tank, 22 ... Drying box, 23 ... Continuous cutting machine,
24. Cooling device.

Claims (7)

  Numerous pieces of fiber reinforced composite material formed in a linear shape with a length within a certain range from a fiber reinforced composite material formed by impregnating a string-like reinforcing fiber bundle with an adhesive synthetic resin. A fixing plate for fixing a tensile material, wherein the fixing plate is formed into a plate shape, and an insertion hole penetrating in the thickness direction is formed in a central portion on a plane.   2. The fixing plate for fixing a tensile material according to claim 1, wherein the fixing plate is formed into a plate shape by heating and pressing in the thickness direction with respect to the plurality of fiber reinforced composite material pieces.   The fixing plate for fixing a tensile material according to claim 1, wherein a reinforcing fiber sheet is adhered to one surface in the thickness direction. A string-like fiber reinforced composite material formed by impregnating a string-like reinforcing fiber bundle with an adhesive synthetic resin is cut into lengths within a certain range in the length direction, and a number of fiber-reinforced composite material pieces are cut. Forming, and
A step of filling the fiber-reinforced composite material piece between a lower mold and an upper mold that can form a plate-like space having a hole in the central portion when combined with each other and are relatively movable in opposite directions;
While the lower mold and the fiber reinforced composite material in the upper mold are heated to a temperature at which the synthetic resin can be melted, fluidized, or softened to have adhesiveness, Pressurizing the mold and the upper mold in a direction facing each other with a pressure that can reduce the volume of the total fiber-reinforced composite piece existing in the lower mold and the upper mold,
The fixing plate according to claim 1 or 2, wherein the lower plate and the upper die have a plate-like insertion hole in the center and can bear a compressive force in the thickness direction. A method for manufacturing a fixing plate for fixing a tensile material. A string-like fiber reinforced composite material formed by impregnating a string-like reinforcing fiber bundle with an adhesive synthetic resin is cut into lengths within a certain range in the length direction, and a number of fiber-reinforced composite material pieces are cut. Forming, and
Filling the fiber-reinforced composite material piece between a lower mold and an upper mold that can form a plate-like space when combined with each other and are relatively movable in opposite directions; and
While the lower mold and the fiber reinforced composite material in the upper mold are heated to a temperature at which the synthetic resin can be melted, fluidized, or softened to have adhesiveness, Pressing the mold and the upper mold in a direction facing each other with a pressure capable of reducing the volume of the total fiber-reinforced composite material pieces present in the lower mold and the upper mold, and molding a plate-like body;
Including a step of forming an insertion hole in the center of the plate-like body,
3. A method for producing a fixing plate for fixing a tensile material, wherein the fixing plate according to claim 1 or 2 capable of bearing a compressive force in a thickness direction.   In the step of filling the fiber reinforced composite piece between the lower mold and the upper mold, a reinforcing fiber sheet is disposed on the lower mold before filling the fiber reinforced composite piece, or the lower mold A reinforcing fiber sheet is placed on the fiber-reinforced composite piece filled on the surface, the lower mold and the upper mold are pressed as they are, and the reinforcing fiber sheet is pasted on at least one surface in the thickness direction. 6. The method of manufacturing a fixing plate for fixing a tensile material according to claim 4, wherein the fixing plate according to claim 3 is manufactured. The tension plate fixing fixing plate according to any one of claims 4 to 6, wherein in the step of pressing the fiber reinforced composite material piece, the heating of the fiber reinforced composite material piece is repeated a plurality of times. Production method.

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