JP2017067093A - Junction structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a junction structure capable of realizing a proof strength superior to that of a prior art high strength bolt junction structure, reducing the number of bolts, releasing a bolt strength, saving energy of a surface treatment at a junction surface, performing a bolt fastening work, and saving energy for management of fed axial force.SOLUTION: A junction structure 100 comprises: a connected member 10 having a bolt hole 11; two additional plates 20, 20 arranged to hold both surfaces of the connected member 10 including the bolt hole 11 therebetween; a bolt 30 passing through bolt holes 21, 21 opened in the additional plates 20, 20 and the bolt hole 11 of the connected member 10; and a nut 31 fastened by the bolt 30. A salient part 22a of a step part 22 protruded around the bolt holes 21, 21 of the two additional plates 20, 20 is fitted into an inside part of the bolt hole 11 of the connected member 10.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a structure of a portion where steel plates, steel frames, and the like constituting various steel structures are joined to each other.

  About the joining structure of steel plates, conventionally, a plurality of steel plates placed close to each other in a butt state are sandwiched between a plurality of accessory plates, and high strength bolts are passed through the accessory plates and steel plates in a laminated state and tightened with nuts, so-called, A high-strength bolt friction joint structure is common.

  However, the yield strength of the joint in the conventional high strength bolt joint structure is almost always determined by the slip strength of the high strength bolt, and in order to increase the yield strength (ie, slip strength) It is necessary to increase the bolt shaft diameter, adopt high-strength bolts, and devise friction surface treatment.

  On the other hand, as a means for improving the problems of the conventional high-strength bolt joint structure, for example, there is a “high-strength bolt joint structure” described in Patent Document 1. As described in FIG. 2 and the like in Patent Document 1, this “high-strength bolt joint structure” has a bolt hole of a member to be joined through which a shaft portion of the high-strength bolt is inserted, in the thickness direction of the member to be joined. The pressure supporting hole portion is formed so as to be gradually reduced in diameter toward the inner side and the hole surface is formed in a tapered shape.

  In addition, the supporting plate is provided with a pressure supporting portion that is bent at a concentric bent portion positioned on the radially outer side of the bolt hole and fitted into the pressure supporting hole portion. Then, the pair of members to be joined and the accessory plate are fastened with a high-strength bolt, and the supporting pressure portion of the accessory plate is pressed with a washer member, and the supporting pressure portion is pressed against the hole surface of the supporting pressure hole portion of the subject member. By doing so, a “high-strength bolt joint structure” is formed.

JP 2010-53956 A

  The “high-strength bolt joint structure” described in Patent Document 1 can improve the proof stress over the conventional high-strength bolt joint structure without applying friction surface treatment and without increasing the strength of the high-strength bolt. However, since the periphery of the bolt hole of the member to be joined and the periphery of the bolt hole of the accessory plate have complicated shapes, it takes a lot of labor and time to form these shapes. Further, since a washer member having a special shape is also necessary, there is a lack of versatility.

  Therefore, the problem to be solved by the present invention is to demonstrate the proof stress and rigidity superior to the conventional high strength bolted joint structure, reduce the number of bolts, relax the bolt strength, save labor in the surface treatment of the joint surface, and Another object of the present invention is to provide a joint structure capable of saving labor for bolt tightening construction and introduction axial force management.

  The joining structure of the present invention includes a plurality of members to be joined that are arranged on the same plane with their end faces facing each other with a predetermined space therebetween, and a plurality of attachments that are arranged so as to sandwich the member to be joined and the space between them. A joint structure comprising: a plate; a bolt hole formed in the accessory plate; and a bolt penetrating a space between the members to be joined; and a nut fastened to the bolt, wherein the bolt of the accessory plate A stepped portion protruding around the hole toward the member to be joined is fitted into the bolt hole of the member to be joined.

  Here, it is desirable that the outer peripheral shape of the step portion is a circular shape concentric with the bolt hole of the accessory plate.

  The step height of the stepped portion is preferably 1/6 to 1/2 of the thickness of the accessory plate.

  On the other hand, a washer can be attached to a portion of the bolt located in the bolt hole of the member to be joined.

  Further, the outer periphery of the stepped portion on the convex shape side may be displaced in the diameter increasing direction.

  The present invention demonstrates superior proof strength than conventional high-strength bolt joint structures, reduces the number of bolts, eases bolt strength, saves the surface treatment of the joint surface, and tightens bolts and introduces axial force management. A joining structure capable of saving labor can be provided.

It is sectional drawing which shows the joining structure which is embodiment of this invention. It is a partially-omission perspective view which shows the surface part of the attachment board which comprises the joining structure shown in FIG. It is a partially-omission perspective view which shows the back surface part of the attachment board shown in FIG. It is sectional drawing in the XX line in FIG. It is sectional drawing which shows the state which applied external force to the joining structure shown in FIG. 1, and deform | transformed. It is sectional drawing which shows the state which applied the external force to the joining structure shown in FIG. 5, and further deform | transformed. It is sectional drawing which shows the junction structure which is other embodiment. It is sectional drawing which shows the junction structure which is other embodiment.

  Hereinafter, based on FIGS. 1-7, the junction structure 100,200,300 which is embodiment of this invention is demonstrated.

  A joining structure 100 shown in FIG. 1 includes a joined member 10 in which a bolt hole 11 is opened, and two attachment plates 20 and 20 arranged so as to sandwich both surfaces of the joined member 10 including the bolt hole 11. A bolt 30 passing through the bolt holes 21, 21 provided in the attachment plates 20, 20 and the bolt hole 11 of the member to be joined 10, and a nut 31 tightened with the bolt 30 are provided. The projecting portion 22 b side of the stepped portion 22 projecting around the bolt holes 21, 21 of the two attachment plates 20, 20 is fitted into the bolt hole 11 of the joined member 10. A washer 32 is inserted into the bolt 30 between the nut 31 and the accessory plate 20.

  The two splicing plates 20 and 20 constituting the joining structure 100 shown in FIG. 1 are formed of plate members (steel plates). As shown in FIGS. 2, 3, and 4, the step portion 22 extends around the bolt hole 21 of the accessory plate 20 from one surface (front surface 20 a) to the other surface (back surface 20 b). It is formed in a protruding state. That is, as shown in FIG. 2, the concave portion 22a of the step portion 22 is formed on the surface 20a of the splicing plate 20, and the convex portion 22b of the step portion 22 is formed on the back surface 20b side of the splicing plate 20 as shown in FIG. Is formed.

  2 to 4, the shape of the outer periphery 22as of the concave portion 22a of the step portion 22 and the shape of the outer periphery 22bs of the convex portion 22b of the step portion 22 are concentric with the center line 21c of the bolt hole 21 of the accessory plate 20. It has a circular shape. Although the manufacturing method of the attachment plate 20 is not limited, for example, a steel plate having a bolt hole 21 is placed on a die, and the stepped portion 22 is forcibly subjected to shear deformation around the bolt hole 21 by a die punch. A forming method called a step-out press can be used. The splicing plate 20 formed by the stepping press may be referred to as “stepping opening steel plate”, and the distance indicated by the arrow Y in FIG. 4 may be referred to as “stepping height”. The step height Y of the step portion 22 is preferably 1/6 to 1/2 of the thickness of the support plate 20.

  Here, based on FIGS. 5 and 6, a deformation mechanism and the like when an external force is applied to the joining structure 100 shown in FIG. 1 will be described. As shown in FIG. 5, external forces P1 and P2 that are parallel to each other and are 180 degrees different from each other act on the member to be joined 10 and the accessory plates 20 and 20 constituting the joining structure 100, and the external forces P1 and P2 are joined. When the frictional resistance force between the member 10 and the supporting plates 20 and 20 is exceeded, the bolt hole 11 of the member to be joined 10 and the stepped portion 22 move relatively in opposite directions, and are indicated by an arrow A. When the inner peripheral surface 11a of the bolt hole 11 of the joined member 10 and the outer peripheral surface 22be (see FIG. 4) of the convex portion 22b of the stepped portion 22 of the accessory plate 20 come into contact with each other, the movement is temporarily performed. Stop.

  As described above, when the external forces P1 and P2 further increase after the inner peripheral surface 11a and the outer peripheral surface 22be come into contact with each other, as shown in FIG. The left side) is deformed in a shearing direction with respect to the main body of the attachment plate 20 and is deformed so that the bolt hole 21 of the attachment plate 20 is flattened. When the above-described deformation occurs, the outer peripheral surface 30a of the bolt 30 and the inner peripheral surface 21a of the bolt hole 21 of the accessory plates 20 and 20 come into contact with each other at portions indicated by arrows B and C in FIG. Thereafter, when the external forces P1 and P2 further increase, the stepped portion 22 undergoes shear failure or bearing failure, and the shaft portion of the bolt 30 undergoes shear failure, and the magnitude of the external force at that time becomes the maximum yield strength.

  The joint structure 100 shown in FIG. 1 exhibits excellent proof stress, with a maximum proof stress approximately 1.2 to 1.5 times that of a conventional high-strength bolt joint structure. , The labor saving of the surface treatment of the joint surface, and the labor saving of the bolt tightening construction and the introduction axial force management can be achieved.

  Next, based on FIG. 7, FIG. 8, the joining structures 200 and 300 which are other embodiment of this invention are demonstrated. 7 and 8, the same structure and function as those constituting the joining structure 100 shown in FIG. 1 are denoted by the same reference numerals as those shown in FIG. 1. Description is omitted.

  In the joining structure 200 shown in FIG. 7, a plurality of washers 33 are attached to a portion 30 b of the bolt 30 that is located in the bolt hole 11 of the member to be joined 10. As shown in FIG. 7, the plurality of washers 33 are sandwiched between the convex portions 22 b and 22 b of the step portions 22 and 22 of the two attachment plates 20 and 20 without any gap. The washer 33 may be singular.

  In the absence of the washer 33, when the tightening axial force of the bolt 30 is introduced, the step-up height Y (see FIG. 4) of the stepped portion 22 increases, but there is a washer 33 as in the joining structure 200 shown in FIG. In this case, deformation of the step-out height Y can be suppressed. Also, when the bolt 30 is tightened when there is no washer 33 and the ratio of the step-up height Y to the plate thickness of the accessory plate 20 (steel plate) is large, the standard bolt axial force of the current high-strength bolt friction joint is introduced. Before being done, the deformation in the axial direction of the bolt 30 of the stepped portion 22 may become excessive, resulting in shear failure.

  However, when a plurality of washers 33 are attached to the bolt 30 as in the joining structure 200 shown in FIG. 7, the shear fracture can be prevented, and a standard bolt axial force can be introduced. It can be expected that a frictional force is generated between the screw and the washer 33. Further, if the total thickness of the plurality of washers 33 is made smaller than the gap between the attachment plates 20 and 20 (the gap between the opposing convex portions 22 and 22), the tightening force of the bolt 30 and the nut 31 can be increased. By changing it, the deformation amount of the step-up height Y (see FIG. 4) can be easily controlled.

  Next, in the joining structure 300 shown in FIG. 8, the outer periphery 22bs of the convex portions 22b of the step portions 22 and 22 of the two attachment plates 20 and 20 are displaced in the diameter increasing direction. In the case of the joining structure 300, the outer periphery 22bs of the convex portion 22b of the splicing plate 20 is in contact with the inner peripheral surface 11a of the bolt hole 11 of the member to be joined 10 in the initial stage. There is an advantage that rigidity is high when external forces P1 and P2 shown in FIG.

  In the joining structure 300 shown in FIG. 8, as a method of displacing the outer periphery 22bs of the convex portions 22b of the step portions 22 and 22 of the two spur plates 20, 20, for example, a nut 31 is attached to the bolt 30. When tightening, there is a method in which the bolt holes 21 of the two stepped portions 22 and 22 are deformed so as to approach each other with a strong force. In this case, if the washer 40 having the pressing surface 41 that forms a part of the side surface of the truncated cone instead of the washers 32 and 34 is used, the aforementioned deformation in the diameter increasing direction is facilitated. Can do.

  Further, the joint structure 300 shown in FIG. 8 can suppress the occurrence of a deformation mechanism as shown in FIG. 5 when an external force is applied. That is, in the joint structure 300, it is possible to transmit force between the inner peripheral surface 11a of the bolt hole 11 and the outer periphery 22bs of the convex portion 22b of the stepped portion 22 from the stage of a small deformation state when an external force is applied. Therefore, an increase in initial rigidity can be expected.

  Further, in the joining structure 300, since the deformation mechanism shown in FIG. 6 can be expected from the initial stage when the external forces P1 and P2 shown in FIG. 5 start to be applied, the yield strength is reduced even once in the deformation process. The maximum proof stress can be exhibited with a small deformation. From the above, it can be said that the joint structure 300 is a joint structure having high rigidity and high yield strength.

  The joint structures 100, 200, and 300 described with reference to FIGS. 1 to 8 exemplify the joint structure of the present invention, and the joint structure of the present invention is limited to the joint structures 100, 200, and 300 described above. Not. 1, 5, 6, and 7, Torcia-type high-strength bolts are used, and in the embodiment shown in FIG. 8, hexagonal high-strength bolts are used. Therefore, various types of bolts such as hexagonal high-strength bolts, torcia-type high-strength bolts, and ordinary bolts can be used.

  Further, the splicing plate 20 having the stepped portion 22 around the bolt hole 11 is not limited to various steel structures (joint structure of steel and steel), but is a joint structure of steel and concrete, steel and wood. It can be widely used in bonded structures, bonded structures of concrete, bonded structures of wood, or bonded structures of other materials (for example, FRP).

  The joint structure of the present invention can be widely used in the fields of the civil engineering construction industry, the construction industry, and the like as a steel sheet or steel frame joint structure in various steel structures.

DESCRIPTION OF SYMBOLS 10 To-be-joined member 11,21 Bolt hole 20 Bending plate 20a Front surface 20b Back surface 21a Inner peripheral surface 21c Center line 22 Stepped part 22a Concave part 22as, 22bs Outer part 22b Convex part 22be Outer part 30 Bolt 30a Outer part 31 Nuts 32, 33 , 34, 40 Washer 41 Press surface 100, 200, 300 Joint structure P1, P2 External force

Claims (5)

  A member to be joined having a bolt hole, a plurality of attachment plates arranged so as to sandwich the bolt hole and the member to be joined, a bolt hole provided in the attachment plate, and a bolt hole of the member to be joined. A joint structure including a bolt passing therethrough and a nut fastened to the bolt, wherein a stepped portion projecting around the bolt hole of the accessory plate is provided inside the bolt hole of the member to be joined. Inserted joint structure.   The joint structure according to claim 1, wherein an outer peripheral shape of the stepped portion is a circular shape concentric with a bolt hole of the accessory plate.   The joining structure according to claim 1 or 2, wherein a step-up height of the step portion is 1/6 to 1/2 of a thickness of the attachment plate.   The joining structure according to any one of claims 1 to 3, wherein a washer is attached to a portion of the bolt to be joined in a bolt hole of the member to be joined.   The joint structure according to any one of claims 1 to 4, wherein an outer periphery of the convex portion of the stepped portion is displaced in the diameter increasing direction.

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