JP5922993B2 - Structure and lining method using multiple fine crack type fiber reinforced cement composites - Google Patents

Description

  The present invention relates to a structure and a lining method using a plurality of microcracked fiber reinforced cement composite materials, and more particularly, to effectively exhibit the strain hardening characteristics of a plurality of microcracked fiber reinforced cement composite materials. The present invention relates to a structure and a lining method for further improving the bending strength of the steel.

  When reinforcing steel pipe piles supporting steel piers and road bridges, pillar members such as steel pipe piers and reinforced concrete columns, and beam members such as steel girders and reinforced concrete girders that form piers and road bridges, for example, reinforcement objects (column members) In addition, concrete is applied to the surface of the beam member). However, since concrete hardly stretches, it cannot resist the tensile force, and the concrete that has been struck up exclusively resists the compressive force. Therefore, reinforcement that can sufficiently resist the tensile force is performed by winding a steel plate around the surface of the concrete that has been beaten.

  On the other hand, there is a lining method or structure using a short fiber reinforced cement composite material or a multi-fine cracked fiber reinforced cement composite material (hereinafter referred to as HPFRCC) whose elongation strain is increased by mixing reinforcing fibers into concrete. It has been proposed (see Patent Document 1). Short fiber reinforced cement composites and HPFRCC are superior in deformation performance to tensile force compared to ordinary concrete, and form multiple fine cracks to show pseudo-strain hardening characteristics, so expect to improve tensile strength and toughness be able to.

  By the way, in the conventional reinforcement structure by concrete or mortar hoisting for pillar members, etc., the lining part that becomes the reinforcement layer is generally formed only up to the joint surface (boundary surface) with the superstructure and substructure. It is. When a horizontal force is applied to the structure due to an earthquake or the like, a maximum bending moment is usually generated at the joint surface between the column member and the superstructure or substructure (section where the cross section changes greatly). Therefore, in the conventional reinforcement structure where the lining part is formed only up to the joint surface (boundary surface) with the superstructure or substructure, the lining part resists bending compressive stress when a horizontal force acts on the structure. By doing so, resistance to bending tensile stress cannot be expected. That is, even if HPFRCC is used for the lining portion, the conventional reinforcing structure cannot sufficiently exhibit the strain hardening characteristics of HPFRCC, and there is a problem that it is difficult to improve the bending strength of the structure.

JP 2011-184859 A

  An object of the present invention is to provide a structure and a lining method that can effectively exhibit the strain hardening characteristics of a plurality of fine crack-type fiber reinforced cement composites and further improve the bending strength of the object to be reinforced.

  In order to achieve the above object, the structure using the multiple fine crack type fiber reinforced cement composite material of the present invention extends in the axial direction of the object to be reinforced on the surface of the object to be erected to support the superstructure. A reinforcing layer composed of a metal-made stress transmission member fixed and a plurality of microcracked fiber reinforced cement composites covering the surface of the object to be reinforced together with the stress transmitting member is fixed to the object to be reinforced. And the plurality of fine crack type fiber reinforced cement composite materials are inserted into the concrete forming the superstructure, and the concrete and the reinforcing layer are integrated.

Further, another structure of the present invention includes a metal stress transmission member that is fixed to the surface of a reinforcement object to be erected and extends in the axial direction of the reinforcement object, and a reinforcement object together with the stress transmission member. a reinforcing layer composed of a plurality fine cracks type fiber-reinforced cement composite material covering the surface of the body, it is integrated and fixed to the reinforcement subject, further, the reinforcing this plurality fine cracks type fiber-reinforced cement composite material An upper work supported by the object is formed, and the upper work and the reinforcing layer are continuously integrated.

  In the structure of the present invention, for example, the stress transmission member is set to extend to a portion formed of the plurality of fine crack type fiber reinforced cement composite materials of the superstructure. The part of the reinforcing layer that becomes a boundary with the superstructure may be made wider than another part of the reinforcing layer. The multi-fine crack type fiber reinforced cement composite material is an ultra high strength strain hardening type cementitious material having a compressive strength of 90 MPa or more and a tensile ultimate strain of 0.5% or more, and the reinforcing fiber is a high strength polyethylene fiber. It can be a certain specification. For example, a deformed reinforcing bar is used as the stress transmission member.

  The lining method using a plurality of microcracked fiber reinforced cement composite material according to the present invention includes a metal stress transmission member placed on the surface of a reinforcement object that is erected while supporting the superstructure of the structure. After extending and fixing in a direction, a mold frame is arranged outside the surface of the object to be reinforced, and a plurality of fine crack type fiber reinforced cement composite materials are placed between the mold frame and the surface of the object to be reinforced Then, a reinforcing layer is formed by covering and solidifying the stress transmission member, and the reinforcing layer and the object to be reinforced are integrated, and the concrete having the superstructure is formed on the plurality of fine crack-type fibers. A reinforced cement composite material is inserted to integrate the concrete and the reinforcing layer.

According to another lining method of the present invention, after a metal stress transmission member is extended and fixed in the axial direction of the object to be reinforced on the surface of the object to be reinforced, A mold is disposed outside the target portion corresponding to the superstructure of the structure supported by the reinforcement object, and a plurality of fine crack type fiber reinforcements are provided between the mold and the surface of the reinforcement object and in the object portion. A cement composite material is placed , and the stress transmission member is covered and solidified to form a reinforcing layer, and the reinforcing layer and the object to be reinforced are integrated. The target portion is formed of a cement composite material, and the reinforcing layer and the superstructure are continuously integrated.

  In the lining method of the present invention, for example, the stress transmission member is extended to a portion of the superstructure made of the multiple fine cracked fiber reinforced cement composite material. As the plural fine crack type fiber reinforced cement composite material, for example, an ultra high strength strain hardening type cement system having a compressive strength of 90 MPa or more and a tensile ultimate strain of 0.5% or more, and the reinforcing fiber is a high strength polyethylene fiber. A material is used, and a deformed reinforcing bar is used as the stress transmission member.

  According to the present invention, the reinforcing layer formed by the multiple fine crack type fiber reinforced cement composite material and the superstructure are integrated. As a result, the joint surface between the superstructure that generates the maximum bending moment when a horizontal force is applied to the structure and the object to be reinforced (the part where the cross-sectional area changes greatly) is reinforced with multiple microcracked fiber reinforced cement composites. Is done. Therefore, the bending strength of the structure can be further improved by sufficiently resisting the bending compressive stress and bending tensile stress generated by the horizontal force.

It is a front view which illustrates the internal structure of the structure of this invention. It is AA sectional drawing of FIG. When manufacturing the structure of FIG. 1, it is a front view which illustrates the state which fixed the stress transmission member to the surface of the steel pipe pile, and pinched the lower end part of the superstructure. It is a front view which illustrates the state which arranged the formwork in the surface outside of a steel pipe pile. It is a front view which illustrates the structure which extended the stress transmission member to the lower end part of the upper work. It is a front view which illustrates the internal structure of the structure in which the part of the reinforcing layer used as the boundary with the superstructure is wider than the other part of the reinforcing layer. It is a front view which illustrates the internal structure of the structure which the part of the reinforcement layer used as the boundary with the superstructure becomes the taper part wider than the other part of the reinforcement layer. It is a front view which illustrates the internal structure of the structure which made the superstructure and reinforcement layer formed with the multiple fine crack type fiber reinforced cement composite material continue and integrated. It is BB sectional drawing of FIG. FIG. 9 is a front view illustrating a state in which a stress transmission member is fixed to the surface of a steel pipe pier and a reinforcing bar is disposed at the upper end of the steel pipe pier when the structure of FIG. 8 is manufactured. It is a front view which illustrates the state which has arrange | positioned the formwork in the surface outer side of the steel pipe pier of FIG. 10, and the outer side of the object part corresponded to superstructure. It is a front view which illustrates the internal structure of the structure manufactured by making superstructure and a reinforcement layer integrate continuously. It is a front view which illustrates the internal structure of the structure at the time of applying this invention to a steel pipe pier. It is explanatory drawing of a bending test. It is sectional drawing which illustrates the test sample (comparative example) of a bending test. It is sectional drawing which illustrates the test sample (Example 1) of a bending test. It is sectional drawing which illustrates the test sample (Example 2) of a bending test. It is sectional drawing which illustrates the test sample (Example 3) of a bending test. It is sectional drawing which illustrates the test sample (Example 4) of a bending test. 10 is a graph illustrating the bending test result of Comparative Example 1. FIG. 3 is a graph illustrating the bending test result of Example 1. FIG. 6 is a graph illustrating the bending test result of Example 2. FIG. 6 is a graph illustrating the bending test result of Example 3. FIG. 6 is a graph illustrating the bending test result of Example 4. FIG.

  Hereinafter, a structure and a lining method using the multiple fine crack type fiber reinforced cement composite material of the present invention will be described based on the embodiments shown in the drawings.

  As illustrated in FIGS. 1 and 2, the structure 1 of the present invention includes a metal stress transmission member 5 fixed to the surface of a reinforcement object 2 that is erected while supporting the superstructure 6, and a reinforcement object. The reinforcing layer 3 composed of a plurality of microcracked fiber reinforced cement composite material 4 (hereinafter referred to as HPFRCC 4) covering the surface of 2 and the concrete forming the upper work 6 are integrated and constructed. In this embodiment, the steel pipe pile 2a that supports the superstructure 6 such as a pier formed by the concrete 6a and the reinforcing bar 6b is the object 2 to be reinforced. The inside of the steel pipe pile 2a is filled with filled concrete 2c.

  The stress transmission member 5 is extended in the axial direction of the steel pipe pile 2a. The reinforcing layer 3 composed of the stress transmission member 5 and the HPFRCC 4 is fixed to and integrated with the steel pipe pile 2a. Further, the HPFRCC 4 enters the concrete 6a forming the superstructure 6, and the concrete 6a and the reinforcing layer 3 are integrated.

  For example, a deformed reinforcing bar is used as the stress transmission member 5. In addition, various metal bars such as round bar reinforcing bars, steel molds, and the like can be used. The stress transmission member 5 is arrange | positioned at the circumferential direction equal intervals with respect to the steel pipe pile 2a of a cylindrical cross section. For example, twelve deformed reinforcing bars are arranged at equal intervals in the circumferential direction with respect to the steel pipe pile 2a having a cylindrical cross section, and extend parallel to the axial direction (pipe longitudinal direction) of the steel pipe pile 2a. Each stress transmission member 5 is fixed to the outer peripheral surface of the steel pipe pile 2a by spot welding. A symbol W in the drawing indicates a spot welded portion between the steel pipe pile 2 a and the stress transmission member 5. The number and arrangement of the stress transmission members 5 are not limited to this embodiment, and can be determined as appropriate. When the stress transmission member 5 is a deformed reinforcing bar, for example, the specifications of nominal names D6 to D19 are used, and they are arranged at equal intervals of 300 mm to 500 mm.

  The fixing of the stress transmission member 5 to the steel pipe pile 2a is not limited to spot welding, and the stress transmission member 5 can be welded over the entire length. Moreover, the stress transmission member 5 can also be fixed to the steel pipe pile 2a using fixing members, such as a volt | bolt, and a magnet.

  The constituent materials of HPFRCC4 are cement, fine aggregate, admixture, admixture, reinforcing fiber, and water. For example, ordinary Portland cement is used as the cement. For example, silica sand is used as the fine aggregate. For example, fly ash is used as the admixture. As the admixture, for example, a high performance AE water reducing agent and an antifoaming agent are used. As the reinforcing fibers, for example, polyvinyl alcohol (PVA) fibers and high-strength polyethylene fibers are used. The diameters of these fibers are about 0.04 mm, the length is about 12 mm, the elastic modulus is about 40.6 GPa, and the tensile breaking strength is about 1690 MPa. It is. The reinforcing fiber mixing rate is about 0.5% to 2.0% by volume.

Among HPFRCC4, an ultrahigh strength strain-hardening cement material (hereinafter referred to as UHP-SHCC) having both ultrahigh strength and ultrahigh toughness may be used. The constituent materials of UHP-SHCC are cement, fine aggregate, admixture, admixture, reinforcing fiber, and water. For example, ordinary Portland cement is used as the cement. For example, silica sand is used as the fine aggregate. As the admixture, for example, silica fume and an expansion material are used. As the admixture, for example, a high performance AE water reducing agent and an antifoaming agent are used. As the reinforcing fibers, for example, high-strength polyethylene fibers (diameter of about 0.012 mm, density of about 0.97 g / cm ² , elastic modulus of about 88 GPa, and tensile breaking strength of about 2700 MPa) are used.

  The layer thickness of the reinforcing layer 3 (HPFRCC 4) is determined on the basis of the strength necessary for reinforcement, but the cover thickness is 30 mm or more in order to prevent corrosion of the stress transmission member 5 or the like.

  When the HPFRCC 4 is used for the reinforcing layer 3, when the steel pipe pile 2a is deformed under a load, a plurality of fine cracks are generated in the HPFRCC 4 under a tensile stress. Demonstrate strength. Furthermore, the steel pipe pile 2a and the HPFRCC 4 are continuously integrated in the extending direction of the stress transmitting member 5 by the stress transmitting member 5 fixed to the outer peripheral surface of the steel pipe pile 2a so as to extend in the axial direction of the steel pipe pile 2a. Therefore, peeling between the steel pipe pile 2a and the HPFRCC 4 is difficult to occur. Therefore, fine cracks are dispersed in a wider range of the HPFRCC 4, and the pseudo strain hardening characteristic of the HPFRCC 4 can be effectively exhibited, and reinforcement with further improved proof stress becomes possible.

  In addition, in the structure 1 of the present invention, the HPFRCC 4 is inserted into the concrete 6a forming the superstructure 6, and the concrete 6a and the reinforcing layer 3 are integrated, so that a horizontal force acts on the structure 1. When this occurs, the joint surface (the portion where the cross-sectional area greatly changes) between the superstructure 6 and the steel pipe pile 2a that generates the maximum bending moment is reinforced by the HPFRCC 4. Therefore, the HPFRCC 4 constituting the reinforcing layer 3 can counter not only the bending compressive stress at the joint surface between the superstructure 6 and the steel pipe pile 2a generated by the horizontal force but also the bending tensile stress. That is, it is possible to further improve the bending strength of the structure 1 by sharing this bending compressive stress over a wide range of the reinforcing layer 3. In this way, the structure can effectively exhibit the strain hardening characteristics of HPFRCC4.

  If the depth (vertical length) at which the HPFRCC 4 is inserted into the concrete 6a forming the superstructure 6 is 10 cm or more, a certain effect can be obtained. For example, the depth is set to 10 cm to 30 cm.

  The procedure for constructing the structure 1 and reinforcing the steel pipe pile 2a is as follows.

  First, as illustrated in FIG. 3, the stress transmission member 5 is spot-welded to the outer peripheral surface of the existing steel pipe pile 2a. Thereby, the stress transmission member 5 is fixed so as to extend in the axial direction of the steel pipe pile 2a over substantially the entire length of the portion to be reinforced. Moreover, the lower end part (concrete 6a) of the existing superstructure 6 is stuck.

  Next, as illustrated in FIG. 4, the mold 8 is arranged with a gap formed on the outer peripheral surface outside of the steel pipe pile 2 a. In this embodiment, a synthetic resin fiber seal cover is used as the mold 8, but a general rigid mold 8 can also be used. The mold 8 is wound around the outer periphery of the steel pipe pile 2a, and the lower end portion and the like are fastened and fixed by a fixing member 9 such as a binding band. An injection pipe 10a is provided at the lower end of the mold 8 fixed to the outer periphery of the steel pipe pile 2a, and an air vent pipe 10b is provided at the upper end.

  Subsequently, HPFRCC4 is inject | poured from the injection pipe 10a, and HPFRCC4 is driven in the clearance between this formwork 8 and the outer peripheral surface of the steel pipe pile 2a. The HPFRCC 4 is also inserted into the portion where the concrete 6a at the lower end of the superstructure 6 is fitted. The reinforcement layer 3 is formed by covering and solidifying the stress transmission member 5a with the placed HPFRCC 4, and the reinforcement layer 3 and the steel pipe pile 2a are integrated. Furthermore, the structure 1 is constructed by fixing the HPFRCC 4 that has entered the lower end portion of the upper work 6 and the concrete 6a that forms the upper work to integrate the concrete 6a and the reinforcing layer 3 together.

  The HPFRCC 4 can also be driven in a state where the stress transmission member 5 is extended to a portion where the concrete 6a of the superstructure 6 is sandwiched (the portion formed by the HPFRCC 4 thereafter). Thereby, as illustrated in FIG. 5, the structure 1 is constructed in which the stress transmission member 5 is extended to a portion formed by the HPFRCC 4 of the upper work 6. In this specification, since the stress is transmitted to the HPFRCC 4 through the stress transmission member 5 extended to the portion formed by the HPFRCC 4 of the upper work 6, it is possible to further improve the proof stress.

  As illustrated in FIG. 6, the widened portion 3 a in which the portion of the reinforcing layer 3 that becomes the boundary with the superstructure 6 is narrower than the superstructure 6 and wider than another portion of the reinforcing layer 2. It can also be made to have specifications. As illustrated in FIG. 7, the widened portion 3 a can be a tapered portion 3 b that decreases in diameter downward.

  By providing the widened portion 3a and the tapered portion 3b in this manner, stress concentration on the portion of the reinforcing layer 3 that becomes the boundary with the upper work 6 is suppressed, which is advantageous in improving the proof stress. In the case of the specifications shown in FIGS. 6 and 7, the stress transmission member 5 can be extended to the portion formed by the HPFRCC 4 of the superstructure 6.

  8 and 9 illustrate another embodiment of the structure 1 of the present invention. In this embodiment, a newly installed steel pipe pile 2a or the like is used as a reinforcement object 2 instead of an existing one. This structure 1 includes a reinforcing layer 3 composed of a stress transmission member 5 fixed to the surface of a steel pipe pile 2a that is erected while supporting the superstructure 6, and an HPFRCC 4 that covers the surface of the steel pipe pile 2a, and the superstructure. 6 is integrated. The stress transmission member 5 is extended in the axial direction of the steel pipe pile 2a. This reinforcing layer 3 is fixed to and integrated with the steel pipe pile 2a. Furthermore, the superstructure 6 is formed of the reinforcing bars 6b and the HPFRCC 4, and the reinforcing layer 3 and the superstructure 6 are integrated.

  In this embodiment, since the HPFRCC 4 and the reinforcing layer 3 forming the superstructure 6 are integrated, the maximum bending moment is generated when a horizontal force is applied to the structure 1 as in the previous embodiment. The joint surface in the vertical direction between the superstructure 6 and the steel pipe pile 2 a is reinforced by the HPFRCC 4. Therefore, the HPFRCC 4 can further improve the bending strength of the structure 1 against the bending tensile stress as well as the bending compressive stress at the joint surface between the superstructure 6 and the steel pipe pile 2a caused by the horizontal force. It has become.

  Furthermore, since the superstructure 6 and the reinforcing layer 3 are seamlessly formed by the same HPFRCC 4, the stress in the portion of the reinforcing layer 3 that becomes the boundary with the superstructure 6 is shared by the HPFRCC 4 in a wider range. It is advantageous for improving the yield strength by suppressing the stress concentration. In the case of the specification shown in FIG. 8, the stress transmission member 5 can be extended to the superstructure 6 (the portion formed by the HPFRCC 4).

  The procedure for constructing the structure 1 and reinforcing the steel pipe pile 2a is as follows.

  First, as illustrated in FIG. 10, the stress transmission member 5 is spot-welded to the outer peripheral surface of the newly installed steel pipe pile 2 a. Thereby, the stress transmission member 5 is fixed so as to extend in the axial direction of the steel pipe pile 2a over substantially the entire length of the portion to be reinforced. Further, a reinforcing bar 6b is arranged at the upper end of the steel pipe pile 2a forming the superstructure 6.

  Next, as illustrated in FIG. 11, the mold frame 8 is arranged with a gap formed outside the outer peripheral surface of the steel pipe pile 2 a, and the mold frame 8 is also arranged outside the target portion corresponding to the superstructure 6. The mold 8 is wound around the outer periphery of the steel pipe pile 2a, and the lower end portion and the like are fastened and fixed by a fixing member 9 such as a binding band. An injection pipe 10a is provided at the lower end of the mold 8 fixed to the outer periphery of the steel pipe pile 2a.

Next, HPFRCC 4 is injected from the injection pipe 10a, and the HPFRCC 4 is driven in the gap between the mold 8 and the outer peripheral surface of the steel pipe pile 2a and the target portion corresponding to the superstructure 6. As illustrated in FIG. 12, the stress transmission member 5 is covered and solidified by the HPFRCC 4 that has been placed, and the reinforcing layer 3 is formed to integrate the reinforcing layer 3 and the steel pipe pile 2a. Furthermore, the superstructure 6 is formed by the HPFRCC 4, and the reinforcing layer 3 and the superstructure 6 are continuously connected and integrated to construct the structure 1.

  In the case of this embodiment, the specification having the widened portion 3a and the tapered portion 3b described above can also be used. Moreover, it can also be set as the specification which extended the stress transmission member 5 to the part formed by HPFRCC4 of the superstructure 6. FIG.

  As illustrated in FIG. 13, the structure 1 of the present invention can also be a reinforcement object 2 such as a land pile. For example, the steel pipe pier 2b that supports the superstructure 6 such as a road bridge can be used as the object 2 to be reinforced. In this embodiment, similarly to the above-described embodiment, the HPFRCC 4 constituting the reinforcing layer 3 is inserted into the concrete 6a forming the upper work 6 through the lower end portion of the existing upper work 6, and the concrete is formed. 6a and the reinforcement layer 3 can also be integrated. Alternatively, the superstructure 6 can be newly provided by the HPFRCC 4 so that the reinforcing layer 3 and the superstructure 6 can be continuously integrated. In addition, the various specifications described above can be applied.

  It is also possible to integrate the HPFRCC 4 constituting the reinforcing layer 3 into the concrete 7a forming the substructure 7 so that the concrete 6a and the reinforcing layer 3 are integrated.

  In the present invention, not only the steel pipe pile 2a and the steel pipe pier 2b but also the reinforced concrete pile, the reinforced concrete column, and the like can be used as the reinforcement object 2.

  As shown in FIG. 14, a steel pipe having the same specifications (length: 2000 mm, outer diameter: 89.1 mm, thickness: 4.2 mm) is used as reinforcement object 2, and five types are provided with an upper work 6 and a lower work 7 on this steel pipe. A test sample S (comparative example, Examples 1 to 4) of the structure was prepared. Four deformed reinforcing bars (D6) were fixed to the outer peripheral surface of the steel pipe at equal intervals in the circumferential direction as stress transmission members 5 on the outer peripheral surface of the steel pipe and extended in the axial direction of the steel pipe. And the reinforcement layer 3 of thickness 21mm which consists of these deformed reinforcing bars and UHP-SHCC4 was provided so as to be integrated with the steel pipe. Inside the steel pipe is filled concrete. The outer shape of the upper work 6 and the lower work 7 is a square of 300 mm × 300 mm.

The combination of UHP-SHCC4 used in the comparative example and Examples 1 to 4 has a water binder ratio (W / B) of 0.22, a sand binder ratio (S / B) of 0.10, and a reinforcing fiber mixing rate. (Vf) is 1.5%. B represents a binder (cement + silica fume + expansion material). High-strength polyethylene fibers (diameter 0.012 mm, length 6 mm, density 0.97 g / cm ² , elastic modulus 88 GPa, tensile breaking strength 2700 MPa) were used as the reinforcing fibers.

  Each test sample S was supported at both ends by the support member 11 at a support span of 1800 mm, and a bending test was performed by applying a load F at a position 800 mm from the support member 11 on the upper work 6 side. The relationship between the load F at that time and the displacement at the loading point is shown in FIGS.

  As shown in FIG. 15, the comparative example is a specification in which the UHP-SHCC 4 is provided only up to the boundary surfaces of the upper work 6 and the lower work 7. The deformed reinforcing bar was extended from the boundary surface between the steel pipe and the substructure 7 to 100 mm before the boundary surface with the superstructure 6.

  As shown in FIG. 16, Example 1 is a specification in which UHP-SHCC 4 is inserted into a concrete 6 a forming the superstructure 6 to a position of 100 mm from the boundary surface. Other specifications are the same as the comparative example.

  As shown in FIG. 17, the second embodiment is a specification in which the superstructure 6 is formed of UHP-SHCC 4 and is continuous with the reinforcing layer 3 and seamlessly integrated. Other specifications are the same as the comparative example.

  Example 3 is a specification in which the deformed reinforcing bar 5 of Example 1 shown in FIG. 16 is extended from the boundary surface to a position of 100 mm as shown in FIG.

  Example 4 is a specification in which the deformed reinforcing bar 5 of Example 2 shown in FIG. 17 is extended from the boundary surface to a position of 100 mm from the boundary surface as shown in FIG.

  As shown in FIGS. 20 to 24, it can be seen that in Examples 1 to 4, the maximum value of the load F is larger than that of the comparative example, and the proof stress is improved.

  By comparing the results of Examples 1 and 3 (FIGS. 21 and 23) with the results of Examples 2 and 4 (FIGS. 22 and 24), the UHP-SHCC 4 forming the reinforcing layer 3 is replaced with the concrete 6a of the superstructure 6. It can be seen that the same strength improvement effect can be obtained by the specification of entering the upper work 6 and the specification of forming the superstructure 6 by UHP-SHCC4 and integrating it with the reinforcing layer 3 formed by UHP-SHCC4.

  By comparing the results of Examples 1 and 2 (FIGS. 21 and 22) with the results of Examples 3 and 4 (FIGS. 23 and 24), the deformed rebar 5 is extended to UHP-SHCC 4 forming the superstructure 6. It can be seen that, when installed, the proof stress is improved as compared with the case where it is not extended.

DESCRIPTION OF SYMBOLS 1 Structure 2 Reinforcement object 2a Steel pipe pile 2b Steel pipe pier 2c Filled concrete 3 Reinforcement layer 3a Widening part 3b Taper part 4 HPFRCC (UHP-SHCC)
5 Stress transmission member (deformed bar)
6 Superstructure 6a Concrete 6b Reinforcement 7 Substructure 7a Concrete 8 Form 9 Fixing member 10a Injection pipe 10b Air venting pipe 11 Supporting member S Test sample W Spot weld

Claims (10)

  A metal stress transmission member that is fixed by extending in the axial direction of the reinforcement target body on the surface of the reinforcement target body that is erected while supporting the superstructure, and a plurality that covers the surface of the reinforcement target body together with the stress transmission member A reinforcing layer composed of a fine crack type fiber reinforced cement composite material is fixed and integrated with the object to be reinforced, and the multiple fine crack type fiber reinforced cement composite material is applied to the concrete forming the superstructure. A structure using a plurality of fine crack-type fiber reinforced cement composite materials, characterized in that the concrete and the reinforcing layer are integrated. Metal stress transmission member fixed to the surface of the object to be reinforced extending in the axial direction of the object to be reinforced, and multiple fine crack type fiber reinforcement covering the surface of the object to be reinforced together with the stress transmission member a reinforcing layer composed of a cement composite material, said reinforcing object fixed to be integrated in, addition, this plurality fine cracks type fiber-reinforced cement composite material to form a superstructure that is supported by the reinforcement subject A structure using a multi-fine crack type fiber reinforced cement composite material, wherein the superstructure and the reinforcing layer are continuously integrated.   The multiple microcracked fiber reinforced cement composite material according to claim 1 or 2, wherein the stress transmission member is extended to a portion of the superstructure formed by the multiple microcracked fiber reinforced cement composite material. The structure used.   The portion of the reinforcing layer serving as a boundary with the superstructure is wider than another portion of the reinforcing layer. The multi-fine crack type fiber reinforced cement composite material according to any one of claims 1 to 3 is used. Structure.   The multi-fine crack type fiber reinforced cement composite material is an ultra high strength strain hardening type cementitious material having a compressive strength of 90 MPa or more and a tensile ultimate strain of 0.5% or more, and the reinforcing fiber is a high strength polyethylene fiber. A structure using the multiple fine crack type fiber reinforced cement composite material according to any one of claims 1 to 4.   The structure using the multiple fine crack type fiber reinforced cement composite material according to any one of claims 1 to 5, wherein the stress transmission member is a deformed reinforcing bar.   After a metal stress transmission member is extended and fixed in the axial direction of the object to be reinforced on the surface of the object to be reinforced standing to support the superstructure of the structure, a mold is formed outside the surface of the object to be reinforced. A reinforcing layer is formed by placing a frame, placing a plurality of fine cracked fiber reinforced cement composite materials between the mold and the surface of the object to be reinforced, and covering and solidifying the stress transmission member. The reinforcing layer and the object to be reinforced are integrated, and the concrete that forms the superstructure is inserted into the plurality of microcracked fiber reinforced cement composite material so that the concrete and the reinforcing layer are integrated. A lining method using a plurality of microcracked fiber reinforced cement composites characterized by the above. A structure that is supported by the outer surface of the object to be reinforced and the object to be reinforced after a metal stress transmission member is extended and fixed in the axial direction of the object to be reinforced on the surface of the object to be reinforced. Placing a mold on the outside of the target portion corresponding to the superstructure, and placing a plurality of fine cracked fiber reinforced cement composite material between the mold and the surface of the reinforcing target body and on the target portion, A reinforcing layer is formed by covering and solidifying the stress transmission member, and the reinforcing layer and the object to be reinforced are integrated , and further , the target portion is formed by the multiple fine crack type fiber reinforced cement composite material. Then, the lining method using a plurality of fine crack type fiber reinforced cement composite materials, wherein the reinforcing layer and the superstructure are continuously integrated.   9. The multiple fine crack type fiber reinforced cement composite material according to claim 7 or 8, wherein the stress transmission member is extended to a portion of the superstructure formed by the multiple fine crack type fiber reinforced cement composite material. Lining method.   As the plural fine crack type fiber reinforced cement composite material, an ultra high strength strain hardening type cementitious material having a compressive strength of 90 MPa or more, a tensile ultimate strain of 0.5% or more, and a reinforcing fiber of high strength polyethylene fiber. The lining method using the multiple fine crack type fiber reinforced cement composite material according to any one of claims 7 to 9, wherein a deformed reinforcing bar is used as the stress transmission member.

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