JP6662519B2 - Joint structure - Google Patents

Description

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

  For the joining structure of steel plates, conventionally, a plurality of steel plates arranged close to each other in a butt state are sandwiched by a plurality of attachment plates, and high-strength bolts are penetrated through the attachment plates and the steel plates in a laminated state and tightened with nuts, so-called, A high-strength bolt friction joining structure is common.

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

  On the other hand, as a solution to the problem 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, the “high-strength bolt joining structure” is configured such that a bolt hole of a joined member through which a shaft portion of a high-strength bolt is inserted is formed in a thickness direction of the joined member. It is formed to have a pressure-bearing hole having a tapered hole surface with a diameter gradually reduced toward the inside.

  Further, the supporting plate is provided with a supporting portion which is bent at a concentric bent portion located radially outside the bolt hole and fits into the supporting hole portion. Then, the pair of members to be joined and the attachment plate are tightened with the high-strength bolt, and the supporting portion of the attachment plate is pressed by the washer member, and the bearing portion is pressed against the hole surface of the bearing hole of the member to be joined. By doing so, a “high-strength bolt joint structure” is formed.

JP 2010-53956 A

  The "high-strength bolted joint structure" described in Patent Document 1 can improve the proof stress compared to the conventional high-strength bolted joint structure without applying a 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 attachment plate have complicated shapes, a great deal of labor and time are required to form these shapes. Further, since a washer member having a special shape is required, there is a surface lacking in versatility.

  Therefore, the problem to be solved by the present invention is to exhibit higher strength and rigidity than the conventional high-strength bolted joint structure, to reduce the number of bolts, to reduce the bolt strength, to reduce 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 work and introduction axial force management.

Junction structure of the present invention, the workpieces which bolt holes are opened, the bolt hole and the plurality of served plates disposed so as to sandwich the bonding portion member, the bolt holes are opened in the served plate and A joint structure comprising: a bolt penetrating through a bolt hole of the member to be joined; and a nut fastened to the bolt, wherein one side of the attachment plate is provided around the bolt hole of the attachment plate from the other surface. A step is protruded in a state of protruding in a shearing shape toward the surface ,
The inner peripheral surface of the concave portion of the step portion formed on one surface of the attachment plate forms a right angle with one surface of the attachment plate, and the protrusion of the step portion formed on the other surface of the attachment plate. The outer peripheral surface of the shaped portion forms a right angle with the other surface of the attachment plate,
The convex portion side of the step portion is fitted into the bolt hole of the member to be joined.

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

  Further, it is preferable that the step height of the step portion is 1/6 to 1/2 of the thickness of the attachment 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 step-shaped portion on the convex shape side may be displaced in the radially expanding direction.

  By the present invention, it exerts higher strength than conventional high-strength bolt joint structure, reduces the number of bolts, eases bolt strength, saves surface treatment of joint surface, and manages bolt tightening work and introduction axial force management. A joint structure that can save labor can be provided.

It is sectional drawing which shows the joining structure which is embodiment of this invention. FIG. 2 is a partially omitted perspective view showing a surface portion of an attachment plate constituting the joint structure shown in FIG. 1. FIG. 3 is a partially omitted perspective view showing a back surface portion of the attachment plate shown in FIG. 2. It is sectional drawing in the XX line in FIG. FIG. 2 is a cross-sectional view illustrating a state where an external force is applied to the joint structure illustrated in FIG. 1 and deformed. FIG. 6 is a cross-sectional view showing a state in which an external force is applied to the joint structure shown in FIG. 5 and the joint structure is further deformed. It is sectional drawing which shows the joining structure which is other embodiment. It is sectional drawing which shows the joining structure which is other embodiment.

  Hereinafter, the joining structures 100, 200, and 300 that are embodiments of the present invention will be described with reference to FIGS.

  The joint structure 100 shown in FIG. 1 includes a member 10 having a bolt hole 11 formed therein, and two attachment plates 20, 20 disposed so as to sandwich both surfaces of the member 10 including the bolt hole 11. A bolt 30 penetrates the bolt holes 21, 21 formed in the attachment plates 20, 20 and the bolt hole 11 of the member 10 to be joined, and a nut 31 tightened by the bolt 30. The projecting portions 22 b of the step portions 22 protruding around the bolt holes 21, 21 of the two attachment plates 20, 20 are fitted into the bolt holes 11 of the member 10 to be joined. A washer 32 is inserted into the bolt 30 between the nut 31 and the attachment plate 20.

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

  As shown in FIGS. 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 attachment plate 20. And a circular shape. The method of manufacturing the attachment plate 20 is not limited. For example, a steel plate having a bolt hole 21 is placed on a die, and the periphery of the bolt hole 21 is forcibly deformed by a die punch to form a step 22. A processing method called a stepping press for forming a sheet can be used. The attachment plate 20 formed by the stepping press may be referred to as a "stepped opening steel sheet", and the distance indicated by an arrow Y in FIG. 4 may be referred to as a "stepped height". It is desirable that the stepped height Y of the step portion 22 be 1/6 to 1/2 of the thickness of the attachment plate 20.

  Here, a deformation mechanism and the like when an external force acts on the joint structure 100 shown in FIG. 1 will be described with reference to FIGS. As shown in FIG. 5, external forces P1 and P2, which are parallel to each other and have directions different by 180 degrees, act on the member to be bonded 10 and the attachment plates 20 and 20, which constitute the bonding structure 100, and the external forces P1 and P2 are When the frictional resistance between the member 10 and the attachment plates 20, 20 is exceeded, the bolt hole 11 of the member 10 to be joined and the step portion 22 relatively move in opposite directions, and are indicated by an arrow A. At the point where the inner peripheral surface 11a of the bolt hole 11 of the member 10 to be joined comes into contact with the outer peripheral surface 22be (see FIG. 4) of the convex portion 22b of the step portion 22 of the attachment plate 20, the movement is temporarily stopped. Stop.

  As described above, after the inner peripheral surface 11a and the outer peripheral surface 22be come into contact with each other, when the external forces P1 and P2 further increase, as shown in FIG. 6, one side of the step portion 22 (in FIG. (Left side) is deformed in the shearing direction with respect to the main body of the auxiliary plate 20, and the bolt holes 21 of the auxiliary plate 20 are deformed so as to be flat. 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 attachment 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 step portion 22 is sheared or crushed and the shaft portion of the bolt 30 is sheared, and the strength of the external force at that point becomes the maximum proof stress.

  The joint structure 100 shown in FIG. 1 exhibits an excellent proof strength in which the maximum proof stress is about 1.2 to 1.5 times that of the conventional high-strength bolted joint structure. Mitigation, labor saving in surface treatment of the joint surface, and labor saving in bolt tightening work and introduction axial force management can be achieved.

  Next, joining structures 200 and 300 according to another embodiment of the present invention will be described with reference to FIGS. In the joining structures 200 and 300 shown in FIGS. 7 and 8, parts having the same structures and functions as those constituting the joining structure 100 shown in FIG. 1 are denoted by the same reference numerals as those shown in FIG. 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 located in the bolt hole 11 of the member 10 to be joined. As shown in FIG. 7, the plurality of washers 33 are sandwiched between the convex portions 22 b of the step portions 22 of the two attachment plates 20 without any gap. The washer 33 may be singular.

  In the case where the washer 33 is not provided, when the tightening axial force of the bolt 30 is introduced, the stepped height Y (see FIG. 4) of the step portion 22 increases, but the washer 33 is provided as in the joint structure 200 shown in FIG. In this case, deformation of the step height Y can be suppressed. Further, when the bolt 30 is tightened in a case where the washer 33 is not provided and the ratio of the step-out height Y to the thickness of the attachment plate 20 (steel plate) is large, the standard bolt axial force of the current high-strength bolt friction joining is introduced. Before this, the axial deformation of the bolt 30 of the step portion 22 becomes excessive, which may cause shear failure.

  However, when a plurality of washers 33 are attached to the bolt 30 as in the joint 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 washer 33 and the washer 33. If the total thickness of the plurality of washers 33 is made smaller than the gap between the attachment plates 20 (the gap between the opposing convex portions 22, 22), the tightening force of the bolt 30 and the nut 31 is reduced. By changing it, the amount of deformation of the step height Y (see FIG. 4) can be easily controlled.

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

  In the joining structure 300 shown in FIG. 8, as a method of displacing the outer periphery 22bs of the convex portion 22b of the step portion 22, 22 of the two attachment plates 20, 20, in the radially increasing direction, for example, a nut 31 is attached to the bolt 30. When tightening, there is a method in which the bolts 21 of the two step portions 22 are deformed so that the portions of the bolt holes 21 approach each other. In this case, if the washer 40 having the pressing surface 41 on one surface forming a part of the side surface of the truncated cone is used instead of the washers 32 and 34, the above-described deformation in the diameter-expanding direction is facilitated. Can be.

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

  Further, in the joint structure 300, since the deformation mechanism shown in FIG. 6 can be expected to occur from the initial stage when the external forces P1 and P2 shown in FIG. 5 start to be applied, the proof stress is reduced once in the deformation process. The maximum proof stress can be exerted with a small deformation without any deformation. From the above, it can be said that the joint structure 300 is a joint structure having high rigidity and high proof stress.

  The joining structures 100, 200, and 300 described with reference to FIGS. 1 to 8 are examples of the joining structure of the present invention, and the joining structure of the present invention is limited to the above-described joining structures 100, 200, and 300. Not done. Also, in the embodiments shown in FIGS. 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. However, various types of bolts such as a hexagonal high-strength bolt, a torcia-type high-strength bolt, and a normal bolt can be used.

  Further, the attachment plate 20 having the step portion 22 around the bolt hole 11 is not limited to various steel frame structures (joint structure between steel and steel), but also includes a joint structure between steel and concrete, and a joint between steel and wood. It can be widely used in a joint structure, a joint structure between concrete, a joint structure between woods, or a joint structure of other materials (for example, FRP or the like).

  INDUSTRIAL APPLICABILITY The joining structure of the present invention can be widely used in fields such as civil engineering and construction as a joining structure of steel plates and steel frames in various steel frame structures.

DESCRIPTION OF SYMBOLS 10 To-be-joined member 11, 21 Bolt hole 20 Attached plate 20a Surface 20b Back surface 21a Inner peripheral surface 21c Center line 22 Step 22a Concave portion 22as, 22bs Outer surface 22b Convex portion 22be Outer surface 30 Bolt 30a Outer surface 31 Nut 32, 33 , 34,40 Washer 41 Pressing 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 disposed so as to sandwich the bolt hole and the member to be joined, and a bolt hole formed in the attachment plate and a bolt hole of the member to be joined are A joint structure comprising a bolt that penetrates and a nut fastened to the bolt, the joint structure being formed in a shear deformation shape from one surface of the attachment plate toward the other surface around a bolt hole of the attachment plate. A step is protruded in a state where it protrudes,
The inner peripheral surface of the concave portion of the step portion formed on one surface of the attachment plate forms a right angle with one surface of the attachment plate, and the protrusion of the step portion formed on the other surface of the attachment plate. The outer peripheral surface of the shaped portion forms a right angle with the other surface of the attachment plate,
A joining structure in which the convex portion side of the step portion is fitted into the bolt hole of the member to be joined.   The joint structure according to claim 1, wherein an outer peripheral shape of the step portion is a circular shape concentric with a bolt hole of the attachment plate.   The joint structure according to claim 1, wherein a stepped height of the step portion is 1/6 to の 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 located in the 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 step portion is displaced in a radially expanding direction.

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