JP2014015807A - Joint structure of steel beam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a joint structure of a steel beam for enabling stable transmission of a load (shearing force) on the steel beam to a steel member such as a column or a girder without causing the fall of the steel beam when fracture occurs in a high strength bolt due to a fire.SOLUTION: In a joint structure B of the steel beam having an attachment plate 10 integrally protruded on a steel member 1 such as the column or the girder and a web 5 of an H-section steel beam 2 joined thereto via a high strength bolt 6, the attachment plate 10 is formed in an L-shape with a joint plate part 10a arranged along the web 5 of the steel beam 2 and joined to the web 5 via the high strength bolt 6 and a supporting plate part 10b arranged below an upper flange 13 of the steel beam 2 along the upper flange 13.

Description

  The present invention relates to a steel beam joint structure.

  Conventionally, as shown in FIGS. 16 to 18, for example, a steel member 1 is used as a joint (joint part) 3 that joins a steel beam 2 of H-shaped steel to a steel member 1 such as a column or a large beam of a steel building. A structure A is often used in which a single plate (gusset plate) 4 is integrally protruded and a web 5 of the steel beam 2 is joined with a high strength bolt 6 (for example, Patent Document 1). reference).

Japanese Patent Laid-Open No. 08-068112

  On the other hand, it is known that the high-strength bolt 6 is deteriorated in strength as compared with ordinary steel materials when exposed to a high temperature. The high-strength bolt 6 may break, and the steel beam 2 may fall along with this. For this reason, in actual design, in consideration of a fire, the number of high-strength bolts 6 is increased or a fireproof coating is allocated so that the temperature of the joint 3 (high-strength bolt 6) does not exceed 550 ° C., for example. I try to increase.

  The phenomenon in which the high-strength bolt 6 breaks due to a fire is a tensile action that acts on the high-strength bolt 6 as the steel beam 2 is cooled and contracted when the steel beam 2 heated by the fire is gradually cooled. It may be caused by shearing force due to force.

  In view of the above circumstances, the present invention can prevent a steel beam from falling even when a high-strength bolt breaks due to a fire, and stabilizes the load (shearing force) acting on the steel beam. It aims at providing the joining structure of the steel beam which can be transmitted to steel members, such as a big beam.

  In order to achieve the above object, the present invention provides the following means.

  The steel beam joint structure of the present invention is a steel beam joint structure in which a spliced plate integrally projecting to a steel member of a column or a beam and a steel beam web of H-shaped steel are joined with a high-strength bolt. The splicing plate is disposed along the web of the steel beam, joined to the web with the high-strength bolt, below the upper flange of the steel beam, and on the upper flange It is characterized by being formed in an L-shape with a supporting plate portion disposed along.

  In this invention, when a high-strength bolt at a joint for joining a steel member of a column or a beam to a steel beam is heated by a fire and the high-strength bolt is broken by any chance, the support plate portion of the accessory plate The upper flange of the steel beam abuts and the steel beam can be supported by the attached plate. As a result, even if a high-strength bolt breaks due to a fire, the steel beam can be prevented from falling, and the load (shearing force) acting on the steel beam can be transmitted to the steel member through the attachment plate. Can do.

  In the steel beam joining structure according to the present invention, the steel beam is integrally formed on the steel member, and the web is interposed below the upper flange on the side opposite to the attachment plate and along the upper flange. It is desirable to provide a side-to-side fall prevention member.

  In this invention, when a high-strength bolt breaks due to a fire, the upper flange on one side abuts the support plate portion of the attachment plate between the steel beam webs, and the steel beam is supported by the attachment plate. The upper flange on the opposite side comes into contact with the side-falling prevention member, and the steel beam can be supported also by this side-falling prevention member. In this way, the both sides of the web are supported by the supporting plate portion of the attachment plate and the side-falling prevention member, so that the steel beam can be prevented from falling down. As a result, even when a high-strength bolt breaks due to a fire, it is possible to reliably prevent the steel beam from falling and to transmit the load acting on the steel beam to the steel member through the attachment plate. it can.

  Furthermore, in the steel beam joining structure according to the present invention, one attachment plate for joining one end of the steel beam in the axial direction to the steel member, and one side of the web of the steel beam between the one side. The other attachment plate for joining the other end portion of the steel beam to the steel member may be arranged on the other side with the web in between.

  In this invention, one end of the steel beam is joined to one side plate having a web disposed on one side, and the other end of the steel beam is joined to the other side having the web disposed on the other side. Since it is joined to the attachment plate, both sides of the steel beam are supported by the support plate portion of each attachment plate, and the steel beam can be prevented from falling down. As a result, even when a high-strength bolt breaks due to a fire, it is possible to reliably prevent the steel beam from falling and to transmit the load acting on the steel beam to the steel member through the attachment plate. it can.

  Further, in the steel beam joining structure of the present invention, one attachment plate for joining one end of the steel beam in the axial direction to the steel member, and the other end of the steel beam as the steel member And the other splicing plate for joining to the steel plate are arranged on one side with the web of the steel beam interposed therebetween, and bolts are respectively attached to the upper flange of the steel beam and the support plate portion of the splicing plate An insertion hole is formed, and the upper flange of the steel beam and the support plate portion of the accessory plate are joined to each other by a side-falling prevention bolt inserted into the bolt insertion hole of the upper flange and the support plate portion. It is preferable that the bolt insertion hole of at least one of the upper flange and the support plate portion is formed as a long hole extending in the material axis direction of the steel beam.

  In this invention, when a high-strength bolt breaks due to a fire, one end side and the other end of the steel beam are attached to the support plate portions of both attachment plates arranged on one side with the web of the steel beam in between. The upper flange on one side of the part side can contact to support the steel beam. In addition, since the upper flange of the steel beam and the support plate portion of the accessory plate are joined by the bolt and nut for preventing the horizontal collapse, the steel beam can be prevented from falling down. As a result, even when a high-strength bolt breaks due to a fire, it is possible to reliably prevent the steel beam from falling and to transmit the load acting on the steel beam to the steel member through the attachment plate. it can.

  In addition, the steel beam is complicated when installing the steel beam by installing a splicing plate on one side between the web on one end side and the other end side of the steel beam. A steel beam can be installed at a predetermined position without being routed, and can be joined to the supporting plate with a high-strength bolt. As a result, even if the high-strength bolt breaks due to a fire, even if it is configured to reliably prevent the steel beam from falling, the workability of the conventional steel beam is ensured. be able to.

  Furthermore, since the bolt insertion hole of at least one of the upper flange on one side and the support plate portion is formed as a long hole extending in the material axis direction of the steel beam, the upper flange of the steel beam is secured with a bolt and nut for preventing the lateral collapse. Even when the support plate portion of the accessory plate is joined, the relative movement of the steel beam and the accessory plate can be allowed by the length of the long hole in the material axis direction. As a result, when the steel beam is thermally stretched due to a fire, or when the steel beam is gradually cooled and contracted after the fire, a large shearing force does not act on the rollover prevention bolt, and the steel beam will surely fall over. It is possible to prevent breakage of the prevention bolt.

  In addition, by connecting the upper flange of the steel beam and the supporting plate part of the supporting plate with the bolts for falling down in the event of a fire, the bolts for falling down will break due to heat during the fire. Can also be prevented. Therefore, even when a high-strength bolt breaks due to a fire, the steel beam can be more reliably prevented from falling and the load acting on the steel beam can be transmitted to the steel member through the attachment plate. it can.

  In the steel beam joint structure of the present invention, when a high-strength bolt of a joint portion breaks due to a fire, the upper flange comes into contact with the support plate portion of the accessory plate, and the steel beam is supported by the accessory plate. Can do. Thereby, even when a high-strength bolt breaks due to a fire, the steel beam can be prevented from falling, and a load acting on the steel beam can be transmitted to the steel member through the attachment plate. Therefore, it is possible to reliably avoid the damage to the steel structure building due to the breakage of the high-strength bolt due to the fire. Furthermore, even if a high-strength bolt placed on the steel beam web breaks in the event of a fire, the shear force can be transmitted reliably, so it is possible to reduce or eliminate the fire-resistant coating of the joint, simplifying the fire-resistant coating work, Can be made into a non-fire-resistant coating connection structure that does not require fire-resistant coating.

It is a front view which shows the joining structure of the steel beam which concerns on 1st Embodiment of this invention. It is the X1-X1 arrow view figure of FIG. FIG. 2 is an X2-X2 arrow view of FIG. 1. It is a figure which shows the condition where the joining structure of the steel beam which concerns on 1st Embodiment of this invention received the fire, and the high strength bolt fractured | ruptured. It is a front view which shows the joining structure of the steel beam which concerns on 2nd Embodiment of this invention. FIG. 6 is a view taken along line X1-X1 in FIG. 5. FIG. 6 is a view taken along line X2-X2 in FIG. 5. It is a figure which shows the condition where the joining structure of the steel beam which concerns on 2nd Embodiment of this invention received the fire, and the high strength bolt fractured | ruptured. It is a front view which shows the joining structure of the steel beam which concerns on 3rd Embodiment of this invention. FIG. 10 is a view taken along line X1-X1 in FIG. 9. It is a front view which shows the joining structure of the steel beam which concerns on 4th Embodiment of this invention. It is a X1-X1 line arrow directional view of FIG. It is the X2-X2 line arrow directional view of FIG. It is a figure which shows the test result which confirmed each part temperature of the steel beam at the time of a fire. It is a front view which shows the example of a change of the joining structure of the steel beam which concerns on 4th Embodiment of this invention. It is a front view which shows the joining structure of the conventional steel beam. It is a X1-X1 line arrow directional view of FIG. It is the X2-X2 line arrow directional view of FIG.

  Hereinafter, a steel beam joining structure according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 4.

  As shown in FIGS. 1 to 3, the steel beam joint structure B of the present embodiment joins a steel column (steel member) 1 such as a square steel pipe of a steel structure building and a steel beam 2 that is an H-shaped steel. A connecting portion (joint portion) 3 that has one side 1a connected to one side 1a of the steel column 1 by welding or the like, and protrudes in the lateral direction T1 and is integrally provided, A plurality of high-strength bolts 6 (and nuts 7) for joining the web 5 of the steel beam 2 and the splicing plate 10 disposed at a predetermined position in the direction T2 with the material axis direction O1 in the transverse direction T1. Configured.

  The splicing plate 10 has one end connected to the upper end of the joining plate portion 10a and the flat joining plate portion 10a disposed along the web 5 so as to be in surface contact with the one surface 5a of the web 5 of the steel beam 2. And a flat support plate portion 10b extending so as to be orthogonal to the bonding plate portion 10a, and is formed in an L shape. Further, a plurality of bolt insertion holes 11 penetrating from one surface to the other surface and arranged at a predetermined interval in the vertical direction T2 are formed in the joining plate portion 10a.

  The splicing plate 10 formed in this way has the support plate portion 10b disposed upward and the joining plate portion 10a disposed in the vertical direction T2, and is connected to a predetermined position substantially at the center in the width direction of one side surface 1a of the steel column 1. And it is protruding.

  Further, the steel beam 2 is disposed on the end 2a side of the web 5 to be joined to the steel column 1 so as to penetrate from the one surface 5a to the other surface 5b of the web 5 with a predetermined interval in the vertical direction T2. A plurality of bolt insertion holes 12 are formed.

  In the steel beam joining structure B of the present embodiment, when the steel beam 2 is disposed at a predetermined position while the one surface 5a of the web 5 is in surface contact with the joining plate portion 10a of the attachment plate 10, the web 5 of the steel beam 2 is disposed. Each of the plurality of bolt insertion holes 12 formed in the communication with the bolt insertion holes 11 formed in the joining plate portion 10a of the accessory plate 10 communicates with each other. The high-strength bolt 6 is inserted into the steel beam 2 and the bolt insertion holes 11, 12 of the accessory plate 10 that are in communication with each other, and passes through the joining plate portion 10 a of the accessory plate 10 and the web 5 of the steel beam 2. By tightening the nut 7 to the shaft portion 6, the steel beam 2 is joined to a predetermined position of the steel column 1 via the accessory plate 10.

  In addition, the steel beam 2 and the attachment plate 10 are joined in this way, and the support plate portion 10b of the attachment plate 10 is located below the upper flange 13a (13) of the one side S1 with the web 5 of the steel beam 2 interposed therebetween. A predetermined interval is provided in the up-down direction T2, and the first side S1 is disposed along the upper flange 13a.

  In the steel beam joining structure B of the present embodiment in which the splicing plate 10 integrally projecting on the steel column 1 and the web 5 of the steel beam 2 are joined by the high-strength bolt 6, FIG. As shown, since the support plate portion 10b of the accessory plate 10 is disposed below the upper flange 13 of the steel beam 2, the high strength bolt 6 of the joint portion 3 is heated by a fire, and the high strength bolt 6 is broken. In this case, the upper flange 13 of the steel beam 2 to be dropped comes into contact with the support plate portion 10b of the attachment plate 10, and the steel beam 2 can be supported by the attachment plate 10.

  Therefore, according to the steel beam joint structure B of the present embodiment, even if the high-strength bolt 6 is broken by a fire, the steel beam 2 can be prevented from falling, The load (shearing force) to be transmitted can be transmitted to the steel column 1 through the attachment plate 10. Therefore, it is possible to reliably avoid the damage to the steel structure building and the steel member due to the breakage of the high-strength bolt 6 due to the fire.

  Moreover, even if the high-strength bolt 6 arranged on the web 5 of the steel beam 2 is broken in the event of a fire, the shearing force can be transmitted reliably, so it is possible to reduce or eliminate the fire-resistant coating of the joint, and simplify the fire-resistant coating work. Furthermore, it is possible to obtain a non-fireproof coating joint structure B that does not require fireproof coating work.

  Next, a steel beam joint structure according to a second embodiment of the present invention will be described with reference to FIGS. Similar to the first embodiment, the steel beam joint structure of the present embodiment relates to the structure of the joint part that joins the steel column (steel member) and the steel beam. Therefore, in this embodiment, the same code | symbol is attached | subjected with respect to the structure similar to 1st Embodiment, and the detailed description is abbreviate | omitted.

  As shown in FIGS. 5 to 7, the steel beam joint structure C of the present embodiment has one end connected to one side 1 a of the steel column 1 and protrudes in the lateral direction T <b> 1, as in the first embodiment. And a plurality of high strength bolts 6 for joining the web 5 of the steel beam 2 disposed in the vertical direction T2 with the material axis direction O1 facing the axial direction O1 in the vertical direction T2 And a nut 7).

  Similarly to the first embodiment, the joining plate 10 is disposed along the web 5 so as to be in surface contact with the one surface 5a of the web 5 of the steel beam 2, and the joining plate 10a. And a flat plate-like support plate portion 10b extending perpendicularly to the portion 10a.

  In the steel beam joint structure C of the present embodiment, the steel beam 2 is disposed at a predetermined position while the one surface 5a of the web 5 is in surface contact with the joint plate portion 10a of the attachment plate 10, and the steel beams communicated with each other. The steel beam 2 is joined to a predetermined position of the steel column 1 through the support plate 10 by inserting the high strength bolt 6 into the bolt insertion holes 11 and 12 of the support plate 10 and the nut 7 and tightening the nut 7. In addition, the steel beam 2 and the attachment plate 10 are joined in this way, and the support plate portion 10b of the attachment plate 10 is located below the upper flange 13a (13) on one side S1 across the web 5 of the steel beam 2. A predetermined interval is provided in the up-down direction T2, and the first side S1 is disposed along the upper flange 13a.

  On the other hand, in the steel beam joining structure C of the present embodiment, as shown in FIGS. 6 and 7, the side-falling prevention member 15 that is integrally protruded with one end connected to one side surface 1a of the steel column 1 is provided. It is prepared for. The side-falling prevention member 15 is formed in a flat plate shape so that the web 5 of the steel beam 2 is interposed below the upper flange 13b (13) on the side opposite to the attachment plate 10 and along the upper flange 13b. The plate surface is disposed in the vertical direction T2. Further, at this time, the lateral fall prevention member 15 is provided so that the upper end surface thereof is disposed at the same position in the vertical direction T2 with the upper surface of the support plate portion 10b of the accessory plate 10.

  In the steel beam joint structure C of the present embodiment, as shown in FIG. 8, first, the support plate portion 10b of the accessory plate 10 is disposed below the upper flange 13 of the steel beam 2, Similar to the first embodiment, when the high-strength bolt 6 of the joint portion 3 is heated by a fire and the high-strength bolt 6 is broken, the steel beam 2 is about to fall onto the support plate portion 10b of the attachment plate 10. The flange 13 abuts and the steel beam 2 is supported by the attachment plate 10.

  Here, since the high-strength bolt 6 is broken and the restraint of the end portion 2a of the steel beam 2 is weakened at a stroke, one of the steel beam 2 is attached to the support plate portion 10b of the accessory plate 10 as in the first embodiment. When the steel beam 2 is supported with only the upper flange 13a in contact, the steel beam 2 may fall down and fall off.

  On the other hand, in the steel beam joint structure C of the present embodiment, the side-falling prevention member 15 is disposed below the upper flange 13b of the other side S2 opposite to the splicing plate 10 with the web 5 of the steel beam 2 interposed therebetween. Therefore, when the high-strength bolt 6 breaks due to a fire, the upper flange 13a on one side abuts the support plate portion 10b of the support plate 10 with the web 5 of the steel beam 2 interposed therebetween, and the steel beam 2 is supported, and the upper flange 13b on the opposite side contacts the side-falling prevention member 15, and the steel beam 2 can be supported also by the side-falling prevention member 15.

  Therefore, according to the steel beam joint structure C of the present embodiment, the both sides S1 and S2 are supported by the support plate portion 10b of the attachment plate 10 and the side-falling prevention member 15 with the web 5 interposed therebetween, so that the steel beam 2 can be prevented from falling off due to a lateral fall, and even when the high-strength bolt 6 is broken by a fire, the steel beam 2 can be reliably prevented from falling.

 As a result, even when the high-strength bolt 6 is broken due to a fire, it is possible to prevent the steel beam 2 from falling more reliably and load acting on the steel beam 2 as compared with the first embodiment. Can be transmitted to the steel column 1 through the attachment plate 10. Therefore, it is possible to reliably avoid the damage to the steel structure building and the steel member due to the breakage of the high-strength bolt 6 due to the fire.

  Further, as in the first embodiment, even if the high-strength bolt 6 arranged on the web 5 of the steel beam 2 is broken in the event of a fire, the shearing force can be transmitted reliably, so that the fireproof coating of the joint can be reduced or eliminated. Thus, it becomes possible to simplify the fireproof coating work and further to make the joint structure C of the fireproof coating that does not require the fireproof coating work.

  Next, with reference to FIGS. 9 and 10 (and FIGS. 1 to 4), a steel beam joining structure according to a third embodiment of the present invention will be described. The steel beam joint structure of this embodiment relates to the structure of the joint part that joins the steel column and the steel beam, as in the first and second embodiments. Therefore, in this embodiment, the same code | symbol is attached | subjected with respect to the structure similar to 1st, 2nd embodiment, and the detailed description is abbreviate | omitted.

  As shown in FIGS. 9 and 10 (see FIGS. 1 to 4), the steel beam joint structure D of the present embodiment is connected to one side 1a of the steel column 1 in the lateral direction as in the first embodiment. The splicing plate 10 is provided so as to protrude integrally with T2, and includes a plurality of high-strength bolts 6 (and nuts 7) for joining the web 5 of the steel beam 2 and the splicing plate 10.

  Further, in the steel beam joining structure D of the present embodiment, as in the first embodiment, the accessory plate 10 is joined to the flat joint plate portion 10a disposed along the web 5 of the steel beam 2. A flat plate-like support plate portion 10b disposed orthogonal to the plate portion 10a is formed in an L shape.

  In the steel beam joining structure D of the present embodiment, the steel beam 2 is disposed at a predetermined position while the one surface 5a of the web 5 is brought into surface contact with the joining plate portion 10a of the attachment plate 10, and the steel beams communicated with each other. The steel beam 2 is joined to a predetermined position of the steel column 1 through the support plate 10 by inserting the high strength bolt 6 into the bolt insertion holes 11 and 12 of the support plate 10 and the nut 7 and tightening the nut 7.

  On the other hand, as shown in FIGS. 9 and 10, the steel beam joining structure D of the present embodiment is provided with one attachment for joining the one end 2 a side of the material axis direction O1 of the steel beam 2 to one steel column 1. The plate 10 and the high-strength bolt 6, and the other accessory plate 10 and the high-strength bolt 6 for joining the other end 2 b side of the steel beam 2 in the material axial direction O1 to the other steel column 1 are configured. Yes.

  And in this joining structure D, one splicing plate 10 is disposed on one side S1 with the web 5 of the steel beam 2 in between, and the other splicing plate 10 is disposed on the other side S2 with the web 5 in between. Configured.

  That is, one splicing plate 10 has its joining plate portion 10a in surface contact with one surface 5a on the one end portion 2a side of the web 5 of the steel beam 2, and the support plate portion 10b on the one side S1 across the web 5. It arrange | positions under the flange 13a and is joined to the web 5 of the steel beam 2 with the high strength volt | bolt 6. FIG. On the other hand, the other attachment plate 10 has its joining plate portion 10 a in surface contact with the other surface 5 b on the other end portion 2 b side of the web 5 of the steel beam 2, and the support plate portion 10 b sandwiching the web 5 on the other side. It is arranged below the upper flange 13b of the side S2 and is joined to the web 5 of the steel beam 2 by high-strength bolts 6. As a result, the steel beam 2 has one end 2a side and the other end 2b side through one web 10 and the other web 10 disposed on the opposite sides S1 and S2 with the web 5 therebetween. The steel column 1 and the other steel column 1 are joined.

  In the steel beam joint structure D of the present embodiment, when the high-strength bolt 6 of the joint portion 3 is heated by the fire and the high-strength bolt 6 is broken, The upper flange 13a (13) of one side S1 of the steel beam 2 to be dropped comes into contact, and the one end 2a side of the steel beam 2 can be supported by the one side plate 10. Further, the upper flange 13b (13) of the other side S2 of the steel beam 2 to be dropped comes into contact with the support plate part 10b of the other attachment plate 10, and the other end 2b side of the steel beam 2 is brought into contact with the other side S2. The supporting plate 10 can support.

  Therefore, in the steel beam joint structure D of the present embodiment, the one end 2a side of the steel beam 2 is joined to one side plate 10 disposed on the one side S1 with the web 5 interposed therebetween. Since the end portion 2b side is joined to the other side plate 10 disposed on the other side S2 with the web 5 interposed therebetween, both sides S1 of the steel beam 2 are interposed between the webs 5 by the support plate portion 10b of each side plate 10. , S2 are respectively supported, and the steel beam 2 can be prevented from falling over. Thus, even when the high-strength bolt 6 is broken due to a fire, the steel beam 2 can be reliably prevented from falling and the load acting on the steel beam 2 can be prevented from being applied to the steel column 1 through the attachment plate 10. Can be transmitted.

  Therefore, according to the steel beam joint structure D of the present embodiment, the steel beam 2 can be more reliably prevented from falling compared to the first embodiment, and a load acting on the steel beam 2 can be applied. It is possible to transmit to the steel column 1 through, and it is possible to more reliably avoid damage to the steel structure building and the steel member due to the breakage of the high-strength bolt 6 due to the fire.

  Similarly to the first embodiment, even if the high-strength bolt 6 disposed on the web 5 of the steel beam 2 breaks in the event of a fire, the shearing force can be reliably transmitted, so the fireproof coating of the joint is reduced or eliminated. It is also possible to simplify the fireproof coating work, and further to make a non-fireproof coating joint structure D that does not require fireproof coating work.

  Next, a steel beam joint structure according to a fourth embodiment of the present invention will be described with reference to FIGS. 11 to 14 (and FIGS. 1 to 4). As in the first, second, and third embodiments, the steel beam joint structure of this embodiment relates to the structure of the joint that joins the steel column and the steel beam. Therefore, in this embodiment, the same code | symbol is attached | subjected with respect to the structure similar to 1st, 2nd, 3rd embodiment, and the detailed description is abbreviate | omitted.

  As shown in FIG. 11 (see FIGS. 1 to 4), the steel beam joint structure E of the present embodiment is connected to one side 1a of the steel column 1 in the lateral direction as in the first and third embodiments. The splicing plate 10 is provided so as to project integrally with the T1, and includes a plurality of high-strength bolts 6 (and nuts 7) for joining the web 5 of the steel beam 2 and the splicing plate 10.

  Further, in the steel beam joint structure E of the present embodiment, the attachment plate 10 is joined to the flat joint plate portion 10a disposed along the steel beam 2 in the same manner as in the first and third embodiments. A flat plate-like support plate portion 10b disposed orthogonal to the plate portion 10a is formed in an L shape.

  Then, the steel beam 2 is arranged at a predetermined position while the surface 5a of the web 5 is in surface contact with the joining plate portion 10a of the splicing plate 10, and the steel beam 2 and the bolt insertion holes 11, 12 of the splicing plate 10 communicate with each other. By inserting the high-strength bolt 6 and tightening the nut 7, the steel beam 2 is joined to a predetermined position of the steel column 1 via the accessory plate 10.

  Furthermore, the steel beam joining structure E of the present embodiment is similar to the third embodiment in that one side plate 10 for joining the material beam direction O1 one end 2a side of the steel beam 2 to one steel column 1 and The high-strength bolt 6, and the other bracing plate 10 and the high-strength bolt 6 for joining the other end 2 b of the steel beam 2 in the material axial direction O1 to the other steel column 1 are configured.

  On the other hand, in the present embodiment, one splicing plate 10 and the other splicing plate 10 are both configured by disposing the web 5 of the steel beam 2 on the one side S1. That is, as for one splicing plate 10 and the other splicing plate 10, the joining plate portion 10 a is in surface contact with the one surface 5 a of the one end 2 a side and the other end 2 b side of the web 5 of the steel beam 2, and the supporting plate The part 10b is arranged below the upper flange 13a (13) of one side S1 with the web 5 interposed therebetween, and is joined to the web 5 of the steel beam 2. As a result, the steel beam 2 is composed of one splint plate 10 and the other splicing plate 10 disposed on the same side S1 with the web 5 interposed therebetween, and the one end 2a side and the other end 2b side are respectively one steel column 1 And the other steel column 1 are joined.

  Furthermore, at this time, as shown in FIGS. 11 to 13, in the steel beam joint structure E of the present embodiment, the bolt insertion holes 16 are formed in the support plate portions 10 b of the respective attachment plates 10. In addition, bolt insertion holes 17 are also formed on the one end 2a side and the other end 2b side of the upper flange 13a on one side S1 of the steel beam 2, respectively. Each of the attachment plates 10 is disposed so that the upper flange 13a of one side S1 of the steel beam 2 and the bolt insertion holes 16 and 17 communicate with each other. Further, by inserting a bolt 18 for side-fall prevention into the bolt insertion holes 16, 17 that are in communication with each other and fastening a nut 19, the support plate portion 10 b of the one attachment plate 10 and the one end portion 2 a side of the steel beam 2 are arranged. The upper flange 13a, the support plate portion 10b of the other accessory plate 10, and the upper flange 13a on the other end 2b side of the steel beam 2 are joined.

  Further, at least one of the bolt insertion holes 16 and 17 formed in the upper flange 13a of the one side S1 and the support plate portion 10b of the accessory plate 10 between the web 5 of the steel beam 2 is inserted. The hole 16 (17) is formed as a long hole extending in the material axis direction O1 of the steel beam 2.

  And in this joining structure E, since one splicing plate 10 and the other splicing plate 10 are both disposed on one side S1 with the web 5 of the steel beam 2 interposed therebetween, the joining portion is caused by a fire. When the high-strength bolt 6 is heated and the high-strength bolt 6 is broken, the one end 2a side and the other end 2b side of the steel beam 2 to be dropped on the support plate portion 10b of the two attachment plates 10 The upper flange 13a contacts and the steel beam 2 is supported.

  In addition, when the steel beam 2 is supported by the two attachment plates 10 disposed on the one side S1 between the webs 5 of the steel beam 2 as described above, the steel beam 2 may fall off due to a sideways fall. However, in the steel beam joint structure E of the present embodiment, the support plate portion 10b of each attachment plate 10 and the upper flange 13a of the steel beam 2 are joined by the side-falling prevention bolts 18 and the nuts 19; The high-strength bolt 6 is broken, and the steel beam 2 supported by the two attachment plates 10 does not fall down.

  Here, an H-section steel beam 2 is installed in the heating furnace, and a load of 0.39 times the normal temperature elastic limit moment of the beam base material is loaded on the steel beam 2 at room temperature, and the load is maintained for 30 minutes. After that, an experiment was conducted in which the steel beam 2 was heated with an ISO834 standard fire temperature curve. And FIG. 14 has shown the result of having measured the temperature change of the upper flange 13 of the steel beam 2, the lower flange, and the web 5. FIG. From this test result, it was confirmed that the temperature of the upper flange 13 is lower than that of the lower flange and the web 5 and the temperature rise of the upper flange 13 is moderately generated during a fire.

  In the steel beam joint structure E of the present embodiment, the support plate portion 10b of each accessory plate 10 is joined to the upper flange 13a of the steel beam 2 having a relatively low temperature in the event of a fire by means of the side-falling prevention bolts 18. I am doing so. For this reason, the side-falling prevention bolt 18 is not easily heated during a fire, and as a result, is not easily broken by a fire. As a result, in the steel beam joint structure E of the present embodiment, the support plate portion 10b of each attachment plate 10 is joined to the upper flange 13a of the steel beam 2 by means of the side-falling prevention bolts 18. It is possible to reliably prevent the steel beam 2 from falling sideways.

  On the other hand, when the steel beam 2 is heated during a fire, the steel beam 2 itself is stretched (linear expansion occurs). Then, when the support plate portion 10b of each attachment plate 10 and the upper flange 13a of the steel beam 2 are joined by the side-falling prevention bolt 18, the side-falling prevention bolt 18 is subjected to a large shear due to the thermal expansion of the steel beam 2 at the time of fire. There is a risk of breaking due to force.

  In contrast, in the steel beam joint structure E of the present embodiment, the two bolts respectively formed on the upper flange 13a of the steel beam 2 through which the side-falling prevention bolts 18 are inserted and the support plate portion 10b of the accessory plate 10 are provided. At least one bolt insertion hole 16 (17) of the insertion holes 16 and 17 is formed as a long hole. For this reason, the thermal elongation of the steel beam 2 generated in the event of a fire is absorbed by the long bolt insertion hole 16, and a large shearing force is exerted on the side-falling prevention bolt 18 due to the thermal elongation of the steel beam 2 in the event of a fire. Does not work. Thus, even when the support plate portion 10b of each attachment plate 10 and the upper flange 13a of the steel beam 2 are joined by the side-falling prevention bolt 18, the side-falling prevention bolt 18 is broken. There is nothing, and it is possible to reliably prevent the steel beam 2 from falling sideways.

  In addition, when the steel beam 2 heated by the fire is gradually cooled, a tensile force is generated as the steel beam 2 contracts, which may cause a shear force to act on the side-falling prevention bolt 18. However, the contraction of the steel beam 2 can of course be absorbed by the bolt insertion hole 16 being formed as a long hole.

  Further, as in the second embodiment and the third embodiment, a supplementary plate (one supplementary plate) 10 is disposed on one side S1 with the web 5 of the steel beam 2 interposed therebetween, and falls sideways on the other side S2. In the case where the prevention member 15 and the attachment plate (the other attachment plate) 10 are provided, the steel frame 2 is prevented from interfering with the attachment plate 10 and the side-falling prevention member 15 when the steel beam 2 is installed. The beam 2 needs to be handled in a complicated manner, for example, by tilting or rotating the beam 2.

  On the other hand, as in the present embodiment, the upper flange 13a of the steel beam 2 and the support plate portion 10b of the accessory plate 10 are joined by a side-falling prevention bolt 18, whereby one of the accessory plates 10 and the other accessory plate are joined. If both the plates 10 and the web 5 of the steel beam 2 can be disposed on one side S1, the steel beam 2 does not need to be handled in a complicated manner when the steel beam 2 is installed. Thus, the steel beam 2 can be easily attached from one side.

  Therefore, in the steel beam joint structure E of the present embodiment, when the high-strength bolt 6 breaks due to a fire, both splicing plates disposed on one side S1 with the web 5 of the steel beam 2 interposed therebetween Ten upper flanges 13a on both ends 2a, 2b side of the steel beam 2 can come into contact with the 10 support plate portions 10b to support the steel beam 2. In addition, since the upper flange 13a of the steel beam 2 and the support plate portion 10b of the splicing plate 10 are joined by the bolt 18 and the nut 19 for the side collapse, the steel beam 2 rotates (rolls) and falls off due to the side collapse. Even when the high-strength bolt 6 is broken by a fire, the steel beam 2 can be reliably prevented from falling. Therefore, even when the high-strength bolt 6 is broken due to a fire, the steel beam 2 can be more reliably prevented from falling compared to the first embodiment, and the load acting on the steel beam 2 can be reduced. It can be transmitted to the steel column 1 through the attachment plate 10.

  Further, the upper flange 13a and the support plate portion 10b are joined by the side-falling prevention bolts 18 and nuts 19 so as to prevent the side-falling of the steel beam 2 so that the one end 2a side and the other end of the steel beam 2 are prevented. Even if the splicing plate 10 is disposed on the one side S1 with the web 5 between the portions 2b, it is possible to reliably prevent the steel beam 2 from falling sideways. And, when the steel beam 2 is installed, the auxiliary plate 10 is disposed and joined to one side S1 on both the one end 2a side and the other end 2b side of the steel beam 2 in this way. The steel beam 2 can be installed at a predetermined position without being complicated and can be joined to the accessory plate 10 with the high-strength bolt 6 to improve the workability.

  Further, since at least one bolt insertion hole 16 of the upper flange 13a of one side S1 and the support plate portion 10b is formed as a long hole extending in the material axis direction O1 of the steel beam 2, a side-falling prevention bolt 18 and Even when the upper flange 13a and the support plate portion 10b are joined by the nut 19, the steel beam 2 and the attachment plate 10 are relatively moved by the length of the long hole 16 in the material axis direction O1. Can be tolerated. Thereby, when the steel beam 2 is thermally stretched by a fire, or when the steel beam 2 is gradually cooled and contracted after the fire, a large shearing force does not act on the side-falling prevention bolt 18. Therefore, even if it is configured to join the upper flange 13a of the steel beam 2 and the support plate portion 10b of the accessory plate 10 with the side-falling prevention bolt 18, the side-falling prevention bolt 18 will not break. Thus, it is possible to prevent the steel beam 2 from falling down more reliably, and to transmit the load acting on the steel beam 2 to the steel column 1 through the attachment plate 10.

  In addition, the upper-side flange 13a of the steel beam 2 and the support plate portion 10b of the accessory plate 10 which are relatively low in temperature during the fire are joined by the side-falling prevention bolts 18, so that the side-falling prevention bolts 18 are provided. It can also be prevented from breaking due to heat during a fire. Therefore, it can prevent more reliably that the steel beam 2 falls.

  Moreover, even if the high-strength bolt 6 arranged on the web 5 of the steel beam 2 is broken in the event of a fire, the shearing force can be transmitted reliably, so it is possible to reduce or eliminate the fire-resistant coating of the joint, and simplify the fire-resistant coating work. In addition, it is possible to obtain a non-fire-resistant coating joint structure E that does not require fire-resistant coating work.

  The first to fourth embodiments of the steel beam joining structure according to the present invention have been described above. However, the present invention is not limited to the first to fourth embodiments described above, and does not depart from the spirit of the present invention. It can be changed as appropriate.

  For example, in the first embodiment, the second embodiment, and the third embodiment, the joining structures B and C of the steel beam 2 with a gap between the support plate portion 10b of the accessory plate 10 and the upper flange 13 of the steel beam 2 are provided. , D is configured, but without providing a gap between the support plate portion 10b of the attachment plate 10 and the upper flange 13 of the steel beam 2 (with the support plate portion 10 and the upper flange 13 in contact). The joint structure of the steel beam 2 may be configured, and in this case as well, it is possible to obtain the same effects as those of the first, second, and third embodiments.

  In the first to fourth embodiments, the steel member according to the present invention has been described as the steel column 1. However, the steel member is, of course, the case where the large beam and the small beam are joined together. It may be a beam.

  Moreover, in 4th Embodiment, although demonstrated so that the bolt insertion hole 16 of a long hole was provided in the both sides of the one end part 2a side and the other end part 2b side of the steel beam 2, one junction part was demonstrated. A long bolt insertion hole may be provided only on the third side, and even if configured in this way, it is possible to obtain the same effects as in the fourth embodiment.

  Furthermore, in the fourth embodiment, for example, as shown in FIG. 15, the shaft portion 18 a of the side-falling prevention bolt 18 is greatly protruded upward, and the side-falling prevention bolt 18 is inserted into the concrete slab supported by the steel beam 2. You may make it embed | buy the front end side (protrusion part) of the axial part 18a. And if comprised in this way, at the time of a fire, the heat | fever of the junction part 3 of the steel beam 2 and the fall-down prevention bolt 18 can be radiated to the slab through the fall-down prevention bolt 18, and the high strength bolt 6 and the side An effect of suppressing the breakage of the fall prevention bolt 18 can be obtained.

1 Steel column (steel member)
1a One side surface 2 Steel beam 2a One end portion 2b The other end portion 3 Joint portion (joint portion)
4 Conventional plate (gusset plate)
5 Steel beam web 5a One side 5b Other side 6 High strength bolt 7 Nut 10 Attached plate 10a Joint plate portion 10b Support plate portion 11 Bolt insertion hole 12 Bolt insertion hole 13 Upper flange 13a One side upper flange (one upper flange )
13b Upper flange on the other side (the other upper flange)
15 Side-falling prevention member 16 Bolt insertion hole (long hole)
17 Bolt insertion hole 18 Side fall prevention bolt 18a Shaft portion 19 Nut A Conventional steel beam joint structure B Steel beam joint structure C Steel beam joint structure D Steel beam joint structure E Steel beam joint structure O1 Steel beam Material axis direction S1 One side S2 The other side T1 Horizontal direction T2 Vertical direction

Claims (4)

In the steel beam joint structure, which is formed by joining a spliced plate integrally projecting to a steel member of a column or beam and a steel beam web of H-shaped steel with a high-strength bolt,
The splicing plate is disposed along the steel beam web, joined to the web with the high-strength bolt, below the upper flange of the steel beam, and along the upper flange A steel beam joining structure characterized in that it is formed in an L shape including a support plate portion to be disposed. In the steel beam joint structure according to claim 1,
A side-falling prevention member is provided so as to project integrally with the steel member, and is disposed below the upper flange opposite to the attachment plate and along the upper flange, with the web interposed therebetween. Steel beam joint structure characterized by In the steel beam joint structure according to claim 1,
One attachment plate for joining one end of the steel beam in the axial direction to the steel member is disposed on one side of the web of the steel beam,
A joining structure for a steel beam, wherein the other attachment plate for joining the other end of the steel beam to the steel member is disposed on the other side with the web in between. . In the steel beam joint structure according to claim 1,
One splicing plate for joining one end of the steel beam in the axial direction to the steel member and the other splicing plate for joining the other end of the steel beam to the steel member, Disposed on one side between the webs of the steel beams;
In addition, bolt insertion holes are formed in the upper flange of the steel beam and the support plate portion of the attachment plate, respectively, and a side-falling prevention bolt inserted into the bolt insertion holes of the upper flange and the support plate portion. It is configured to join the upper flange of the steel beam and the support plate portion of the attachment plate,
The steel beam joining structure, wherein the bolt insertion hole of at least one of the upper flange and the support plate portion is formed as a long hole extending in the material axis direction of the steel beam.

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