JP2008266963A - Pole and beam junction structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pole and beam junction structure, solving the problem of the prior art, simply constructing a pole and beam junction part in a steel rigid frame structure with high quality, and further easily coping with alteration of joining level of some beams. <P>SOLUTION: This pole and beam junction structure adopts bolt junction in a multi-layer steel structure rigid frame. The pole is formed of a square steel pipe having uniform wall thickness, and the wall thickness of the square steel pipe is set based on the pulling force of a bolt to which the tensile force joining the pole and the beam is applied. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a joint structure between columns and beams in a steel frame frame.

  When connecting columns and beams with bolts such as high-strength bolts in steel-framed structures, the connection with the column-side beam (hereinafter referred to as “the connection with the column-side beam”) It has been common practice to increase the stiffness of a beam joint by increasing the thickness of the "joint". For example, Patent Document 1 discloses a technology for increasing the rigidity of a beam joint by attaching a metal fitting 3 made of cast steel thicker than the square steel pipe column 2 to the beam joint of the square steel tube column 2 by welding. . Patent Document 2 discloses a technique in which a thick portion 11a is provided on a part of the longitudinal direction of the steel pipe column 11 by induction heating and compression, and a beam is joined to the thick portion 11a.

  On the other hand, in a detached house that is often built in an area where the height of the building is severely limited, as disclosed in Patent Document 3, as a device for constructing a comfortable and effective living space within the range of the height restriction. It has been proposed to change the floor level of the middle floor in the grid of the part, use the lower floor with increased floor height as a public space such as a living room, and use the upper floor with reduced floor height as storage space Yes. By adopting such a space configuration, it is possible to configure a comfortable space on the lower floor with a high ceiling and easy to secure sunlight and lighting without increasing the height of the building, and the ceiling height of the upper part is reduced. The space that is not suitable for living can also be used effectively.

JP 61-1113941 A Japanese Patent Laid-Open No. 7-292771 JP-A-6-323010

  However, in the case of the technique disclosed in Patent Document 1, there is a problem that a process of welding the joint metal is required for the number of beam joints, which is troublesome and leads to an increase in cost. In addition, since it involves welding work near the beam joint where a large bending moment acts, careful attention should be paid to all beam joints so as not to cause problems such as material deterioration and welding defects due to the effects of heat. It was necessary to conduct quality control.

  Further, the technique disclosed in Patent Document 2 requires a special and complicated thick wall processing apparatus including the heating device 9, the compression device 4, and the like, and cannot be easily performed at high cost. In addition, it is actually difficult to control the apparatus so that the thickness of the thick portion 11a is kept constant. Furthermore, although the welding process can be omitted, the problem of welding defects is solved, but the thickness increases by compressing the steel pipe, so that internal strain remains in the steel pipe. Therefore, it was necessary to remove the strain by performing a heat treatment as a subsequent process.

  Further, in order to obtain a space configuration as disclosed in Patent Document 3 in a steel frame structure building, it is necessary to change the joining level of some beams in the intermediate layer. In this case, even if any of the techniques of Patent Documents 1 and 2 is used, the connection between the column and the beam is limited to a thick beam joint that has been specially processed. There is a problem in that it has to be provided for each beam joint level, and further labor and cost are increased.

  In particular, in industrialized houses where the cross-sectional dimensions of members such as columns and beams are standardized, multiple thick-walled joints are formed in advance according to the set beam level, or multiple column variations are prepared. There is a problem that the number of member varieties becomes enormous. In addition, in order to eliminate the level difference between the floor surface of a Japanese-style room or bathroom and the floor surface of the general part, when the level of a part of the floor is lowered by about 50 mm to 100 mm, the level of the beam supporting the floor depends on the level of the floor lowering In this case, if you try to support a configuration in which multiple beams joined to a single column wrap in the height direction, the variation of thick-walled beam joints will also increase. It was not possible to obtain it, and it was necessary to use a more complicated member structure. Therefore, there has been a problem that the cost reduction effect due to the standardization of the members, which is one of the merits of the industrialized house, is diminished.

  The present invention solves the problems of the prior art, and can easily and high-quality structures for the connection between columns and beams in a steel frame structure, and can easily change the connection level of some beams. An object of the present invention is to provide a joint structure between a column and a beam that can be used.

  A first configuration of a column-to-beam joint structure according to the present invention for solving the above-described problems of the prior art is a column-to-beam joint structure by bolt joint in a multi-layer steel frame structure. The column is made of a square steel pipe having a uniform thickness, and the thickness of the square steel pipe is set based on a pulling force of a bolt on which a tensile force for joining the column and the beam acts.

  In the second configuration of the column-to-beam joint structure according to the present invention, a plurality of beam joints in a predetermined layer are formed in advance in the height direction on the column, and the plurality of beam joints It is characterized in that a beam is joined to a beam joint selected from the inside.

  According to the first configuration of the joint structure between the pillar and the beam according to the present invention, the pillar is composed of a square steel pipe at the beam joint and the thickness thereof is set based on the pulling force of the bolt. On the other hand, it is possible to configure the beam joint by a simple operation of drilling a bolt hole without adding a reinforcing member such as a high strength joint metal or providing a thick part. Therefore, the process of processing the beam joint can be greatly simplified.

  In addition, since there is no need to join the members by welding or the like in the beam joint processing step, there is no risk that the dimensional accuracy of the members will be lowered due to the joining accuracy, and there will be no deterioration of the material due to heating, so strength Reliability is improved.

  Furthermore, the thickness of a square steel pipe having a uniform thickness is set based on the pulling-out force of the bolt on which the tensile force used for joining the column and the beam acts, and is uniform at any position on the same cross-section. Therefore, the beam joint can be constructed without any structural problem by simply drilling the bolt holes at arbitrary positions within the range of the rectangular steel pipe having a uniform thickness. Therefore, the floor height of the building can be easily set without taking time and cost as in the prior art.

  In particular, when the present invention is applied to a building in which a member such as an industrialized house is standardized, the floor height can be set freely only by adding a bolt hole, so that the number of members can be increased without increasing the number of members. It is possible to increase the ability to respond to the needs of various customers with a single type of pillar.

  According to the second configuration of the column-to-beam joint structure according to the present invention, a plurality of beam joints in a predetermined hierarchy are provided in advance in the height direction in a portion made of a square steel pipe having a uniform thickness of the column. Since the beam is joined to the beam joint selected from the plurality of beam joints, it is possible to easily change the joint level of the beam using exactly the same column.

  Further, in general, a large-scale work of changing the floor level not only in a new construction but also in a renovation work can be performed relatively easily because no member processing such as welding is required.

  Below, the most preferable form of the junction part structure of the pillar and beam which concerns on this invention is demonstrated. The present invention provides a structure in which a column and a beam are joined to each other by bolting of a multi-layered steel frame frame structure. In particular, the column is composed of a square steel pipe having a uniform wall thickness, while ensuring structural safety. The configuration is realized. The steel frame frame to which the present invention is applied is not particularly limited as long as it is a multi-layered structure of two or more stories.

  The column used in the present invention has a portion made of a square steel pipe having a uniform wall thickness, and if it is constituted to have at least one beam joint in the portion made of this square steel pipe. Good. Except for this condition, there is no limitation on the position and number of joints between the above-mentioned square steel pipe and other square steel pipes, and it may be appropriately determined in consideration of the stress acting on the structure, the manufacturing cost of the column, and the like.

  A square steel pipe having a uniform wall thickness means that there is no difference in wall thickness between the seam portion and the general portion, and the thickness is equal. As the square steel pipe having such a configuration, there is no seamless, that is, a square steel pipe (so-called seamless pipe) having no welded seam in the cross section, a welded box-shaped cross section column, a cold-formed square steel pipe, a hot-formed square steel pipe. However, a seamless pipe that does not require welding in the manufacturing process is preferable.

  When a square steel pipe having a uniform wall thickness is joined to another square steel pipe of approximately the same external shape and the cross section of the column is changed halfway, the joint (hereinafter referred to as the joint between the square steel pipes is referred to as “column / column joint”). Part ”) may be joined by any method of welding and bolt joining, and can be constructed using a known technique. It should be noted that the column / column joint is preferably joined at an intermediate portion where the stress acting is small and the influence is small, avoiding the vicinity of the beam joint where a large stress acts.

  The pull-out force of the bolt on which the tensile force for joining the column and the beam acts is generated by a bending moment acting on the beam, and causes out-of-plane deformation on the column flange surface facing the beam joint. If there is not enough strength and rigidity on the column flange surface of the beam joint, there will be a problem that the column will be broken, or the beam end will rotate and the horizontal deformation of the building will be excessive. In addition, when a bolt hole with a threaded hole is drilled and a bolt is screwed to join a bolt, the strength of the threaded portion of the bolt hole that can withstand the pulling force of the bolt is required, and when sufficient strength is not ensured, The bolts come off and the connection between the pillars and beams is released, the floor falls and the building collapses. In addition, when bolts are joined using known one-side bolts without cutting screws in the bolt holes, if the strength around the bolt holes is not secured, the bolts come off and the connection between the columns and beams is released and the building is removed. It leads to collapse.

  In general, when a horizontal load assuming seismic force is applied to a multi-story portal frame structure, the bending moment acting on the beam end (joint with the column) of each layer increases as the beam connection level increases (column base) The greater the height from the to the junction, the greater). Therefore, the thickness of the rectangular steel pipe having the uniform wall thickness of the column used in the present invention is such that the column is deformed / ruptured when the stress acting on the beam end is the largest within the range of the assumed beam joint level. It is set so that structural safety can be ensured without doing so. In other words, at the highest level of beam joints assumed for rectangular steel pipes with uniform wall thickness, structural safety is ensured without column deformation or breakage around the bolt hole where the largest pulling force acts near the flange. Is set to be secured.

  The beam used in the present invention is not particularly limited as long as it has a strength capable of establishing a rigid frame structure such as H-shaped steel, groove-shaped steel, and steel pipe. Further, not only the pillars on the second floor or higher, but also the foundation beam connected to the column base on the first floor can be bolted. In that case, it is desirable that at least the end portion of the foundation beam to be joined to the column is made of steel or steel concrete.

  The form of the joint between the column and the beam in the present invention may be any form as long as it is a form that realizes a rigid joint by bolt joining, that is, a form designed to transmit a bending moment between the pillar and the beam. There is no particular limitation. For example, a joining plate having a joining surface with a column at the end of the beam is attached by welding or the like, and the joining plate is in contact with the joining surface with the beam on the column side and is bolted with a high-strength bolt or the like. After joining a pair of T-shaped cross-section joints (so-called split tees) to the joint surface with the beam, the joints and the ends of the upper and lower flanges of the beam are bolted with a high-strength bolt or the like. Can be applied.

The bolt used in the present invention is preferably a one-side bolt that does not require welding such as a nut or a screw plate processed on the inner surface side of the column. Among the one-side bolts, the type in which the bolt protrudes from the inner surface side of the column and the bulge is formed and fastened to the protruding portion is likely to cause a problem of interference between adjacent bolts as the thickness of the column increases. In such a case, it is preferable to use a bolt of a type in which a bolt is cut into a bolt hole of a pillar and screwed. Moreover, it is preferable that it is a Torcia type | mold bolt with easy fastening torque management. As such a bolt, there is a special high-strength bolt disclosed in Japanese Utility Model Publication No. 5-575.
(First embodiment)

  Next, a first embodiment of the present invention will be specifically described with reference to the drawings. A present Example is an example of the junction part structure of a pillar and a beam in the industrialized house of a three-story steel frame ramen structure. FIG. 1 is a diagram showing a planar grid configuration of the frame of this embodiment. FIG. 2 is a diagram showing the overall structure of the frame of this embodiment. FIG. 3 is a view showing a joint portion between a pillar and a large beam used in this embodiment. FIG. 4 is a diagram showing pillars used in this embodiment. FIG. 5 is a side view of a frame in which the same member is used and the floor height (ceiling height) is changed.

  As shown in FIGS. 1 and 2, the house of this embodiment is a three-story building composed of a plurality of planar grids. As shown in FIG. 2, the basic frame is composed of a plurality of columns 1 in the form of continuous columns from one layer to three layers and a plurality of large beams 2 connecting adjacent columns 1 in each layer, and the direction of the carry Is composed of 6 plane grids with 3 spans and 2 spans in the wife direction, and is constructed on the upper part of the foundation 3 that is continuous in a grid pattern. The column base is joined to the foundation by an exposed fixed column base method disclosed in Japanese Patent Laid-Open No. 01-203522.

  After constructing this basic frame, the floor is constructed by placing a small beam between the opposing large beams 2 and placing a floor panel made of ALC (lightweight cellular concrete) on the upper flange of the beam. An outer wall is constructed by attaching a wall panel made of ALC to the large beam 2 of the part, and the housing is completed.

  As shown in FIG. 3, the girder 2 joined to the column 1 is made of H-shaped steel, and all the girder 2 in all the layers are 250 mm in beam formation, 125 mm in flange width, 9 mm in flange thickness, 9 mm in web The thickness is unified to 6 mm. The joint portion of the beam 2 with the column 1 is constituted by a joint plate 2a welded to both ends of the beam 2. The joint plate 2a has two rows symmetrically from the center in the horizontal direction and the like in the vertical direction. A total of eight holes 2b having the same diameter and four steps are formed at intervals. A total of six holes in the upper 2 tiers and the lowermost tier of the holes 2 b are holes for inserting bolts 4 used for joining to the pillar 1. Note that the two holes in the second step from the bottom are holes for inserting and aligning “shino” in the joining operation, and are not used for joining the column and the beam. The said structure is common to all the big beams 2 of all the hierarchy including a dimension.

  As shown in FIG. 4, the column 1 is a through column made of a square steel pipe having an outer dimension of 150 mm square, and is a portion from the junction of the column base plate 1 a to the column / column junction 1 b formed in the middle portion. (The lower column 1c) is a seamless square steel pipe having a thickness of 22 mm (that is, a seamless pipe having no welded seam in the cross section), and is configured without a joint in the length direction. (The upper column 1d) is formed of a square steel pipe having the same outer dimensions as the lower column 1c but a thickness of 4.5 mm to 6.0 mm thinner than the lower column 1c.

  The column 1 has a standard joint level of the large beam 2 so that the standard floor height (space between the upper end surfaces of the large beams) of each layer is 2870 mm. In accordance with the reference joining level, a hole 1h that is threaded so as to correspond to the hole 2b of the joining plate 2a of the large beam 2 is drilled, and the joint portions (first beam joint portions) 1e1, 1f1 with the large beam 2 are formed. 1g1 is formed. Like the holes 2b of the large beam 2, a total of six holes 1h in the upper two steps and the lowermost step are holes into which the bolts 4 to be joined to the large beam 2 are screwed, and the two holes in the second step from the bottom are positions. It is a hole for alignment.

  Further, the second beam joint portion is configured in the same manner as the first beam joint portion 1e1 at a position 1000 mm downward and a position 1000 mm upward from the reference joint level (first beam joint portion 1e1) on the second floor. 1e2 and a third beam joint 1e3 are formed. Similarly, on the third floor, the second beam joint is configured in the same manner as the first beam joint 1f1 at positions 1000 mm downward and 1000 mm above the reference joint level (first beam joint 1f1). A portion 1f2 and a third beam joint portion 1f3 are formed.

  The column / column joint 1b is formed above the third beam joint 1f3 of the third-floor large beam by a known joint structure described in JP-A-6-180026, JP-A-8-60740, and the like. ing.

  As described above, the thickness of the square steel pipe constituting the lower column 1c is such that the largest bending moment acts on the end of the large beam 2 and the largest pulling force (245 kN per high-strength bolt) acts on the bolt. At the level, structural safety is confirmed by the following procedure.

(1) The pulling-out force of the bolt 4 satisfying the retained strength joint (joint so that the collapse of the joint with the column does not precede the collapse of the large beam) is obtained for the large beam 2 having a predetermined material strength and cross-sectional dimension. (That is, the pull-out force of the upper and lower bolts 4 at which the largest pull-out force acts when the beam starts to collapse is obtained.)
(2) A cross section of the column is assumed based on the obtained pulling force of the bolt 4.

(3) Stress is calculated on the assumption that the third-floor beam 2 is joined to the third beam joint 1f3 of the third-floor beam joint, and it is confirmed that the member stress is less than the allowable value.

  As shown in FIG. 3, the girder 2 and the column 1 are joined by bolts (special high strength bolts) 4 disclosed in Japanese Utility Model Publication No. 5-575.

  The main beam 2 is basically joined to the column 1 using the first beam joints 1e1, 1f1, and 1g1, and is set at the reference joint level. The grid shown in FIG. For the grid G1, the large beam 2 is joined using the third beam joint 1e3 at the second floor level to increase the floor height of the first floor, and the joint level is raised from the reference joint level.

  In addition, the boundary between the grid G1 having the reference floor height and the grid G1 in which the floor height has been changed is configured in accordance with each level by appropriately installing a floor made of an ALC panel (not shown). Therefore, the girder 2 is joined to each joining level, the girder 2 joined using the first beam joining part 1e1 and the girder 2 joined using the third beam joining part 1e3. Are arranged side by side.

  By configuring in this way, the floor height (ceiling height) of the first floor can be partially increased, the first floor window can be arranged at a higher position, and it is difficult to ensure lighting. Can be a bright and open space. Further, the interior space can be utilized without waste by utilizing the second floor portion having a lower floor height as a storage space.

  In the above embodiment, the floor height (ceiling height) of the first floor is partially increased. However, as shown in FIG. 5A, the second-floor beam 2 is connected to the second beam joint 1e2 by using the same member. It is also possible to increase the floor height of the second floor partly by joining using the. In this case, the space on the second floor is used as a living room, and the first floor with a lower floor is used as a piloty garage or storage space that does not require a large floor. It can be used without any problems.

  Further, as shown in FIG. 5 (b), by using the second beam joint portion 1f2 to join the third-floor girder 2, the joining level of the third-floor girder 2 is lowered and the third-floor height is increased. Alternatively, as shown in FIG. 5 (c), the third-floor beam 2 can be joined by using the third beam joint portion 1f3 to increase the joint level of the third-floor beam 2 and increase the second-floor height. Is possible.

  Although the said Example is an example which changed the joining level of the big beam 2 of a part grid, it cannot be overemphasized to change the joining level of the big beam 2 about all the grids.

  As described above, a plurality of beam joints 1e and 1f in a predetermined layer are formed in advance in the height direction, and the large beam 2 is joined with the bolt 4 to the beam joint selected from the plurality of beam joints 1e1 to 1f3. To do.

  As a result, it is possible to easily change the beam joining level using the same column 1. In addition, the floor height can be easily changed with the same member configuration without applying special processing or adding special members according to the set level of the beam 2 to be set. Can be easily performed without the effort and cost as in the prior art. Moreover, it can be set as the junction part structure of the pillar and beam in which structural safety was ensured. In addition, the floor height can be set freely simply by adding the bolt hole 1h, so it is possible to increase the ability to respond to the needs of various customers with a single type of pillar without increasing the number of members. it can.

  In addition, the beam joints 1e and 1f can be formed by a simple operation of drilling the bolt holes 1h without reinforcing the pillar 1 by adding a particularly high-strength joint metal or providing a thick part. Therefore, the processing steps for the beam joints 1e and 1f can be greatly simplified.

  In addition, since it is not necessary to join the members by welding or the like in the processing steps of the beam joint portions 1e and 1f, there is no possibility that the dimensional accuracy of the members may be lowered due to the joining accuracy, and deterioration of the material or welding defects due to heating. Therefore, the reliability in terms of strength is improved.

  Further, in general, a large-scale work of changing the floor level not only in a new construction but also in a renovation work can be performed relatively easily because no member processing such as welding is required.

In addition, the use of a square steel pipe having a uniform thickness for the column 1 eliminates the need for special and complex thick wall processing, which can hold down costs and increase the internal strain that occurs when the wall thickness is increased. Does not occur.
(Second embodiment)

Next, a second embodiment will be described with reference to FIG. In the first embodiment, the beam joints 1e and 1f of the respective layers on the column 1 side are set apart from each other to form eight holes 1h per beam joint, but the diameters of the holes 1h are the same. Therefore, as shown in FIG. 6, the holes 1h are continuously formed in the vertical direction at five or more steps at equal intervals. Then, by selecting the hole 1h to be used from the plurality of holes 1h, the joining level of the large beam 2 can be changed at a pitch that is an integral multiple of the pitch of the holes 1h in the vertical direction. Therefore, it is possible to set the joining level of the large beams 2 more finely and to slightly shift the joining level between the large beams 2 joined to the same column 1. For example, the vertical pitch of the holes 1h is set to 50 mm, and the floor level is lowered by 50 mm by shifting the joining level of the large beam 2 downward by one pitch in the area of the tatami mat floor having a thickness of about 60 mm. It can be easily finished without a step difference from the floor of a Western-style room that is thinner than a tatami mat.
(Other examples)

  As another embodiment in the same three-layer industrialized house as the first embodiment, it is possible to adopt a column structure as shown in FIGS. 7 (a) to 7 (g). In FIG. 7, the hatched portion is a seamless square steel pipe with the same cross section, the portion not shaded is a normal column, and the position indicated by a triangle is a column / column joint that joins these two columns. Part 1b.

  FIG. 7A shows an example of a seamless square steel pipe having the same cross section over the entire length of three columns of columns. In this case, the frame can have a higher degree of freedom than the first embodiment.

  FIG. 7B is an example in which a column / column joint 1b is provided in the first layer portion, and the upper part from the column / column joint 1b is a seamless square steel pipe having the same cross section.

  FIG. 7C is an example in which a column / column junction 1b is provided in the second layer portion, and the upper part of the column / column junction 1b is a seamless square steel pipe with the same cross section.

  FIG. 7D shows an example in which a column / column junction 1b is provided in the second layer portion, and the lower part of the column / column junction 1b is a seamless square steel pipe having the same cross section.

  FIG. 7E shows an example in which a column / column joint 1b is provided in the first layer portion and the second layer portion, and the intermediate portion is formed into a seamless square steel pipe with the same cross section.

  FIG. 7 (f) shows an example in which a column / column joint portion 1b is provided in the second layer portion and the third layer portion, and the intermediate portion is a seamless square steel pipe having the same cross section.

  FIG. 7G shows an example in which a column / column joint 1b is provided in the first layer portion and the third layer portion, and the intermediate portion is a seamless square steel pipe having the same cross section.

  Although the column configurations shown in FIGS. 7A to 7G are different in the set number of joining levels, the same operations and effects as the first embodiment are exhibited in any case. The

  The present invention is not limited to steel buildings, and can be widely applied to all steel structures in which columns and beams are rigidly connected with bolts.

It is a figure which shows the planar grid structure of the frame concerning 1st Example. It is a figure which shows the whole structure of the frame of 1st Example. It is a figure which shows the junction part of the large beam used for 1st Example, the pillar of a pillar, and a beam. It is a figure which shows the pillar used for 1st Example. It is a side view of the frame which changed the floor height (ceiling height) concerning the 1st example. It is a block diagram of the junction part of the pillar and beam concerning 2nd Example. It is a fragmentary sectional view showing the composition of the frame concerning other examples.

Explanation of symbols

G, G1 ... Grid 1 ... Column 1a ... Column base plate 1b ... Column / column junction 1c ... Lower column 1d ... Upper column 1e ... Second floor large beam junction 1e1 ... First beam junction 1e2 ... Second beam junction Part 1e3 ... third beam joint 1f ... third-floor large beam joint 1f1 ... first beam joint 1f2 ... second beam joint 1f3 ... third beam joint 1g ... R-floor large beam joint 1h ... hole 2 ... Large beam 2a ... Joining plate 2b ... Hole 3 ... Foundation 4 ... Bolt

Claims (2)

It is a joint structure of columns and beams by bolt connection in a multi-layer steel frame frame,
The column includes a square steel pipe having a uniform thickness in a range including at least one beam joint, and the thickness of the square steel pipe is set based on a pulling force of a bolt that joins the column and the beam. The joint structure between the column and the beam.
  A plurality of beam joints in a predetermined layer are formed in advance in a height direction in a portion made of a square steel pipe having a uniform thickness of the column, and a beam joint selected from the plurality of beam joints is formed. The column-to-beam joint structure according to claim 1, wherein the beam is joined.

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