JP2007077628A - Joint structure of joint and its construction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a joint structure of a joint, which can enhance constructibility, and which can have sufficient durability by reducing a construction cost and preventing the appearance of a crack in a joint surface of a joint space section. <P>SOLUTION: Two or more precast members, which are elongated toward the joint space section 6 forming the joint, are prestressed in the direction of the elongation of them; end plates 21 and 22 are arranged on the end surfaces of them; joint members 18 and 19, which are composed of a prefabricated fiber-reinforced concrete member, are arranged in the joint space section 6; iron plates 25, which are arranged on opposed surfaces, face the end plates 21 and 22 of the precast member, respectively; and the end plates 21 and 22 of the precast members and the iron plates 25 of the joint members are joined together by being welded to one another. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a joint joint structure such as a truss structure and an arch structure in the technical field of architecture and civil engineering, and a construction method thereof.

  The joints represented by the scoring parts such as the truss structure and arch structure are close to rigid joints, so stresses such as bending, shearing, tension, and compression are concentrated, and the scoring points correspond to those stresses. Reinforcing materials such as reinforcing bars and steel materials are concentrated on the part. FIG. 7 shows a reinforced part of the conventional truss structure. The truss structure scoring portion 111 is formed in a joint space 115 between the diagonal members 1112 and 113 made of two PC piles and the upper chord member or the lower chord member 114. In the joint space 115 forming the grading portion 111, a reinforcing bar 116 and a reinforced portion reinforcing bar 117 of the upper chord member or the lower chord member 114 are arranged, and furthermore, end portions of the diagonal members 112 and 113 made of PC piles. The PC steel material 118 is projected from, the concrete space 119 is filled into the joint space 115, and after the concrete 119 is solidified, a tensile force is applied to the PC steel material 118 via the bearing plate 120 installed at the tip of the PC steel material 118. Part reinforcement structure is implemented.

  However, reinforcement members are concentrated and arranged at the rating part of such a rigid frame structure to cope with stress concentration, making it difficult to assemble reinforcing materials such as reinforcing bars at the rating part, resulting in problems in workability. Moreover, when the reinforcing material concentrates on the grade point portion, when the concrete is filled in the grade point portion, there is a problem that the spread of the concrete is deteriorated.

  In order to solve these problems, conventionally, for example, a grading portion reinforcement structure as shown in Patent Document 1 has been proposed. For example, as shown in FIG. 8, the grading portion reinforcing structure includes an upper chord material or a lower chord material 101 constructed of cast-in-place concrete, a PC pile 102 as an oblique material, and a grading portion 103 of a truss structure.

In the joint space portion 104 that constitutes the scoring portion 103 of the truss structure, a reinforcing bar 105 of the upper chord member or the lower chord member 101 and a reinforcing member 106 of the PC pile projecting from the end of the PC pile 102 as the diagonal member project. A formwork (not shown) is installed in the joint space 104 constituting the grading part 103 of the truss structure, and a fiber reinforced concrete 107 mixed with steel fiber, organic fiber, or a combination thereof is placed. Then, the grading part 103 of the truss structure is constructed by curing. In the upper and lower chord members 101, concrete is usually placed by spotting.

The fiber reinforced concrete 107 filled in the joint space 104 has a high strength against stresses such as bending, shearing, tension, and compression, and is therefore arranged in the joint space 104 of the grading portion 103. The amount of the reinforcing reinforcing bars 105 and 106 used can be reduced, and the use of the fiber reinforced concrete 107 improves the fixing property between the filled concrete and the reinforcing members such as reinforcing bars and steel in the joint space 104. For this reason, the amount of reinforcing members used can be further reduced, the difficulty of bar arrangement work, etc. can be reduced, the workability can be improved, the structure can be reduced in weight and cost, and the durability can be increased. It can be set as a characteristic grading point reinforcement structure.
Japanese Patent Application Laid-Open No. 2004-244989

  However, as in the truss structure disclosed in Patent Document 1 above, when the member axial directions of the PC pile 102 extended to the joint space portion 104 are different from each other, or more than three directions with respect to the joint space portion 104 When the PC pile is extended from the above, if the fiber reinforced concrete 107 is placed in the joint space 104, there is a possibility that a crack is generated on the joint surface. Since this crack is the starting point of destruction, it affects the reliability of the strength of the entire structure that constitutes the truss structure. Therefore, it is necessary to suppress the generation as much as possible.

  Further, in the truss structure, where many such grade points are formed, the burden of filling work of the fiber reinforced concrete 107 into the joint space becomes excessive, and the construction period is prolonged accordingly. There was also a point.

  Therefore, the present invention has been devised in view of the above-mentioned problems, and the object is to further improve the workability, reduce the construction cost, and join the joint space portion. It is an object of the present invention to provide a joint structure such as a truss structure, an arch structure, a ramen structure and the like that can provide sufficient durability by preventing cracks on the surface, and a construction method thereof.

  In order to solve the above-described problem, the joint joint structure according to the present invention is extended toward the joint space portion that forms the joint, prestress is introduced in the extension direction, and an end plate is provided on the end surface. It is composed of two or more precast members to be disposed and a fiber reinforced concrete member manufactured in advance, and is disposed in the joint space portion, and an iron plate is disposed on an opposing surface facing the end plate of the precast member. The precast member and the joint member are joined to each other by welding the end plate and the iron plate.

  In order to solve the above-described problem, the construction method of the joint joint structure according to the present invention is applied to two or more precast members that are extended toward the joint space portion that forms the joint portion. In addition, pre-stress is introduced and an end plate is disposed on the end surface, and a joint member made of a fiber reinforced concrete member manufactured in advance is disposed in the joint space portion, and the iron plate disposed on the opposing surface is It is made to oppose the end plate of a precast member, and also it joins by welding the end plate of the said precast member, and the iron plate of the said joint member mutually.

In the joint joint structure to which the present invention is applied, a joint member made of a fiber-reinforced concrete member is disposed in the joint space. For this reason, even at the joint as an intersection of two or more precast members, the fiber reinforced concrete member itself constituting the joint member is resistant to stresses such as bending, shearing, tension, and compression that are applied to the joint space. It becomes possible to do. In addition, in the joint joint structure to which the present invention is applied, since prestress is introduced to the intermediate material and the lower chord material made of the precast member, when a tensile or compressive stress is applied, these are also countered. Can do. On the other hand, when a compressive stress or a bending stress is applied in the joint joint structure, the joint member can counteract it.

  Hereinafter, as a best mode for carrying out the present invention, a joint joint structure applied to a truss structure, an arch structure, a ramen structure, and the like will be described in detail with reference to the drawings.

  The joint joint structure 1 to which the present invention is applied is applied to, for example, a truss structure 2 as shown in FIGS. The arch 2 is disposed on the lower side of the PC floor slab 5, and an upper chord member 13, a lower chord member 14, and an intermediate member 16 represented by a diagonal member, a vertical member and the like are main constituent members. With respect to this truss structure 2, the area around the joint space portion 6 that forms a scoring portion as a joint portion of the truss structure is set as a range where the joint joint structure 1 according to the present invention is applied.

  The mediating material 16 and the lower chord material 14 are each made of a precast member. The intermediary material 16 is extended to the joint space portion 6, prestress is introduced in the extending direction, and an end plate 21 is disposed on the end surface 16a. Further, the lower chord member 14 is also extended to the joint space portion 6, prestress is introduced in the extending direction, and an end plate 22 is disposed on the end face 14a. Incidentally, these end plates 21 and 22 are made of iron plates.

  A joint member 18 made of a fiber-reinforced concrete member manufactured in advance is disposed in the joint space portion 6. FIG. 3 shows the configuration of the joint member 18. When the joint member 18 is disposed in the joint space portion 6, an opposing surface 18 a that faces the end plates 21 and 22 of the mediator material 16 and the lower chord material 14 is formed. Iron plates 25 are disposed on the facing surface 18a. The fiber mixed in the fiber reinforced concrete member constituting the joint member 18 is selected from metal fibers such as steel fibers, vinylon fibers, polypropylene fibers, polyethylene fibers, aramid fibers, and carbon fibers. A combination of one or more fibers is used. Incidentally, the joint member 18 may be mass-produced in advance in a factory or the like according to the specifications of the joint space portion 6 to be disposed.

  When the joint member 18 having such a configuration is disposed in the joint space portion 6, the iron plate 25 disposed on the facing surface 18 a faces the end plates 21 and 22. The joint member 18 is joined to each other by welding the iron plate 25 to the end plates 21 and 22, respectively. A resin mortar 28 is embedded around the iron plate 25 and end plates 21 and 22 welded to each other.

  FIG. 4 shows an example in which the intermediate material 16 is extended from the vertical direction and the lower chord material 14 is extended from the horizontal direction in the joint space portion 6 constituting the grading portion of the truss structure. That is, in the example of FIG. 4, a configuration in which three precast members are extended in the joint space portion 6 is shown, and the same components and members as those in FIG. Therefore, the description below is omitted.

  FIG. 5 shows the configuration of the joint member 19 arranged in the joint space portion 6. When the joint member 19 is disposed in the joint space portion 6, opposing surfaces 19 a that face the end plates 21 and 22 of the mediator material 16 and the lower chord material 14 are formed across the three surfaces of the vertical direction and the horizontal direction. . Iron plates 25 are disposed on the facing surface 19a.

  Next, regarding the construction method of the joint joint structure 1 to which the present invention is applied, the case where the joint member 19 is disposed in the joint space portion 6 where the three precast members are extended as shown in FIG. 4 is taken as an example. Explain.

  First, prestress is introduced in the extending direction with respect to the intermediate member 16 and the lower chord member 14 that are extended toward the joint space portion 6 that forms the rating portion of the truss structure. At this time, when the end plates 21 and 22 are not disposed on the end surfaces 16a and 14a, they may be disposed at this stage.

  Next, the joint member 19 manufactured in advance is arranged in the joint space portion 6. And the iron plate 25 arrange | positioned by the opposing surface 19a in the joint member 19 is made to oppose the intermediate plates 16 and the end plates 21 and 22 of the lower chord material 14. The surface of the iron plate 25 and the surfaces of the end plates 21 and 22 to be opposed to each other are preferably parallel to each other in order to improve the bondability. Furthermore, the end plates 21 and 22 and the iron plate 25 of the joint member 19 are joined together by welding. Finally, the periphery of the end plates 21 and 22 and the iron plate 25 fixed by welding is embedded with resin mortar 28.

  As described above, in the joint joint structure 1 to which the present invention is applied, the joint member 19 made of a fiber-reinforced concrete member is disposed in the joint space portion 4. For this reason, even in the grading point as an intersection of two or more precast members, the fiber reinforced concrete member itself constituting the joint member 19 is subjected to stress such as bending, shearing, tension, and compression that is applied to the joint space portion 6. It becomes possible to oppose. Further, in the joint joint structure 1 to which the present invention is applied, since prestress is introduced into the intermediate member 16 and the lower chord member 14 made of a precast member, when tensile or compressive stress is applied, these are also used. You can counter it. On the other hand, when a compressive stress or a bending stress is applied in the joint joint structure 1, the joint member 19 can counter the stress.

In particular, in the present invention, the fiber reinforced concrete members constituting the joint members 18 and 19 are configured to have a fiber mixing ratio in the range of 0.5 to 5.0%, for example, fiber reinforcement having a design standard strength of 36 N / mm ² . For concrete, a tensile resistance of 1.38 N / mm ² can be taken into account. If the fiber mixing rate is too high, mixing of the fibers becomes difficult.

In the fiber reinforced concrete member constituting the joint members 18 and 19, it is possible to improve the fracture energy G _F representing the crack resistance performance of the concrete. For example, normal concrete having a compressive strength of about 30 N / mm ^{2 is} about 100 N / m, but fiber reinforced concrete having a fiber mixing rate of about 1% can be improved to about 10000 N / m.

  In the joint joint structure 1 to which the present invention is applied, the iron plate 25 and the end plates 21 and 22 are welded and fixed at the joint portion between the joint member 19, the mediating material 16, and the lower chord material 14. As a result, it is possible to prevent cracks generated on the joint surface, which has been a problem in the past, and it is possible to improve the reliability of the entire truss structure.

  Further, in the joint joint structure 1 to which the present invention is applied, the work can be completed only by bringing the joint member 19 manufactured in advance in a factory or the like to the site and arranging it. For this reason, since the burden of the filling operation | work of the fiber reinforced concrete with respect to the joint space part 6 can be eliminated and it becomes possible to improve workability, it becomes possible to shorten a construction period. In particular, the greater the number of rating points present in the truss structure, the greater the effect.

  Furthermore, in the truss structure or the arch structure provided with the joint joint structure 1 having such a configuration, prestress is entirely introduced by the outer cable, and no prestress is introduced into the joint space portion 6. If a prestress is to be introduced into the joint space 6 as well, the joining member becomes enormous. For this reason, in this invention, the joint member 19 which consists of a fiber reinforced concrete member is arrange | positioned instead of introducing prestress also with respect to the joint space part 6. FIG. Thereby, since it becomes unnecessary to arrange a large joining member, it is possible to reduce the size of the score portion itself.

  The joint joint structure 1 to which the present invention is applied is not limited to the above-described embodiment. FIG. 6 shows another configuration example in the joint joint structure 1. In this configuration example, the anchor material 31 is fixed to the intermediate material 16 and the lower chord material 14 from the respective end surfaces 16a, 14a toward the inside of the member. The anchor material 31 may be fixed to end plates 21 and 22 disposed on the end surfaces 16a and 14a, respectively.

  Further, the joint member 19 is configured such that the anchor material 32 is fixed from the facing surface 19a toward the inside of the member, and a fiber-reinforced concrete member is embedded thereon. The anchor material 32 may be fixed to the iron plate 25 disposed on the facing surface 19a. Moreover, this anchor material 32 is extended inside the member of the joint member 19, and the front-end | tip may be bend | folded toward the other opposing surface 19a, as shown in FIG. Thereby, the stress transmission performance of the joint member 19 can be further improved.

  Incidentally, in the above-described example, the case where the anchor materials 31 and 32 are respectively fixed in two rows inside the mediator material 16, the lower chord material 14, and the joint member 19 has been described as an example, but the case is limited to this case. This may be fixed by any number of columns.

  Moreover, in the example mentioned above, although the case where 3-4 precast members were extended in the joint space part 6 was demonstrated as an example, it is not limited to this, Two or more in the joint space part 6 It is also possible to arrange the joint joint structure 1 at any arch structure or truss structure where the precast member has been extended.

  In the above-described example, the joint joint structure 1 applied to the truss structure 2 is described as an example. However, the present invention is not limited to such a case, and is applicable to any arch structure or ramen structure. Of course, you may do.

It is a figure which shows the example of the rigid frame structure to which the junction joint structure which concerns on this invention is applied. It is a figure for demonstrating about the structural example of the junction joint structure to which this invention is applied. It is a figure for demonstrating about the example of the coupling member applied to the junction joint structure to which this invention is applied. It is a figure for demonstrating about the other structural example of the junction-joint structure to which this invention is applied. It is a figure for demonstrating about the other example of the coupling member applied to the junction joint structure to which this invention is applied. It is a figure for demonstrating about the case where an anchor material is provided in the joint member 19. FIG. It is a figure which shows the point part reinforcement structure of the conventional ramen structure. It is another figure which shows the point part reinforcement structure of the conventional ramen structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Joint part joint structure 2 Truss structure 5 PC floor slab 6 Joint space part 13 Upper chord material 14 Lower chord material 16 Intermediary material 18, 19 Joint member 21, 22 End plate 25 Iron plate 31 Anchor material

Claims (4)

Two or more precast members that are extended toward the joint space forming the joint, the prestress is introduced in the extension direction, and the end plate is disposed on the end face;
A pre-fabricated fiber reinforced concrete member, and a joint member that is disposed in the joint space and has an iron plate disposed on the opposing surface facing the end plate of the precast member;
The precast member and the joint member are joined to each other by welding the end plate and the iron plate. The joint joint structure according to claim 1, wherein an anchor material is embedded from the iron plate toward the inside of the joint member. For two or more precast members that are extended toward the joint space that forms the joint, a prestress is introduced in the extension direction, and an end plate is disposed on the end surface thereof,
A joint member made of a fiber reinforced concrete member manufactured in advance is disposed in the joint space portion, and an iron plate disposed on the facing surface is opposed to the end plate of the precast member,
Furthermore, the end plate of the said precast member and the iron plate of the said joint member are joined together by welding, The construction method of the junction joint structure characterized by the above-mentioned. The method for constructing a joint joint structure according to claim 3, wherein the joint member in which an anchor material is embedded from the iron plate to the inside is disposed in the joint space portion.

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