Wood-clad steel frame and method of constructing the same

Abstract

The present invention provides a wood-covered steel frame and a method for constructing the same, which do not involve large joints and require minimal construction effort. [Solution] The wood-covered steel frame 1 according to the present invention comprises a wood-covered column member 7 in which wood material is covered on a steel column 3, a wood-covered beam member 13 in which wood material is covered on a steel beam 9 having an upper flange 9a, a web 9b, and a lower flange 9c, and a joining member 15. The plate-shaped member has a through hole for the joining member, the extended web portion of the steel beam 9 has a web through hole, and the wood material covering the steel beam 9 has a slit that opens towards the lower flange 9c side in the range of the web extension portion, and a wood through hole. With the web extension portion inserted into the gap of the joining member 15, the wood-covered column member 7 and the wood-covered beam member 13 are joined by pin members 26 inserted into the wood through hole, the joining member through hole and the web through hole.

Description

Technical Field

[0001] The present invention relates to a framework of a workpiece and a method for constructing the same, and particularly to a framework made of steel columns and steel beams covered with wood and a method for constructing the same.

Background Art

[0002] From the viewpoint of reducing carbon dioxide emissions and carbon fixation, the use of wood in buildings has been actively promoted, and its use has increased from small-scale buildings to large-scale buildings. On the other hand, there are limitations to increasing the height and size of pure wooden structures. For example, when exceeding seven floors, hybridization with steel materials is required. Examples of hybridization methods include utilization of wood as a non-load-bearing member based on a steel structure, composite structuring with steel materials based on a wooden structure, composite structuring with wood based on a lightweight steel frame structure, and a mixed structure of a steel structure and a wooden structure.

[0003] However, for hybrid members obtained by hybridizing steel materials and wood, there is a problem with the joint structure for how to join the members together. For hybrid members of steel materials and wood, except for the case where wood is separately coated after assembling the steel materials, welding cannot be used, so it is necessary to consider mechanical joining methods.

[0004] Here, conventional column-beam joint structures and hybrid members will be described. <Normal Column-Beam Joint of Steel Structure> In the case of pin joint, the web of the H-shaped steel beam is aligned with the gusset plate provided on the steel column and bolted. Alternatively, it is bolted to the gusset plate via a splice plate. In the case of rigid joint, the upper and lower flanges and the web of a bracket having the same cross-sectional dimensions or more as the H-shaped steel beam provided on the steel column are joined with high-strength bolts via a splice plate. Alternatively, the upper and lower flanges are welded to the diaphragm, and the web is welded to the column skin plate.

[0005] <Joining of Wooden Beam> When joining a wooden beam to a steel column, for example, as disclosed in Patent Document 1, a beam support fitting equipped with a support plate is used to integrally join the steel column and the wooden beam at the joint. Specifically, the ends of the wooden beams have longitudinal slits that penetrate vertically, the beam support hardware has a guide plate with multiple through holes and a support plate that receives and supports the lower surface of the beam, the beam is supported by the support frame by inserting the slits into the guide plate, and multiple drift pins are inserted through the through holes in the guide plate from pin holes provided on the side of the beam.

[0006] <Wood-steel hybrid components> As an example of a wood-steel hybrid member, Patent Document 2 discloses one comprising a steel frame member, wooden members provided on both outer sides of the steel frame member, and fixing members for fixing the steel frame member and the wooden members. When using this wood-steel hybrid member as a beam, the joints are constructed on-site.

[0007] Furthermore, Patent Document 3 discloses a wood-fire-resistant covering surface that forms a wood-fire-resistant covering surface on a steel column using a wood-based component having multiple wood-based materials bonded to it with a thermoplastic resin, while suppressing the shedding of the wood-based component. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Patent No. 6403025 [Patent Document 2] Japanese Patent Publication No. 2022-042750 [Patent Document 3] Patent No. 7369250 [Overview of the project] [Problems that the invention aims to solve]

[0009] When joining column members and beam members, if the wood covering of the beam members is applied after joining the steel beams, the wood covering installation process increases, leading to increased management and construction management effort for the wood materials. When beams and timber materials are pre-integrated, the area to be cut out in the splice plate must be cut out beforehand, and then the timber material must be used to cover it after bolting. This creates additional work steps, increases the scope of post-construction work, and makes it difficult to use the timber material as an exposed element for aesthetic purposes.

[0010] The beam support hardware described in Patent Document 1 is for joining wooden beams, and would need to be enlarged to support steel beams. Furthermore, if the web of a steel beam were to be joined using drift pins in a similar manner, a much larger number of drift pins would be required compared to bolted connections. In addition, during rotational deformation of the beam end, bearing failure may occur sequentially from the outer drift pins, ultimately posing a risk of collapse.

[0011] The wood-steel hybrid member described in Patent Document 2 is a pre-constructed combination of a steel beam and a wood-based material. While it is conceivable to join the steel beams together at the joint using plates and bolts, this would require separate construction, similar to the bolted joints in the aforementioned steel structure. Furthermore, since the bolt heads and threads protrude from the flange and web surfaces, the thickness of the wood cladding must be reduced by the amount of these protruding bolt heads and threads. If the thickness of the wood cladding is reduced, in the event of a fire, this wood cladding may burn through quickly, causing combustion to progress from the joints and potentially failing to achieve the required fire resistance performance.

[0012] Patent Document 3 describes a covering structure for steel pipe columns using wood-based materials, but it does not mention the floor boundary portion. Even if there is no premature layered delamination of the wood-based materials and the specified fire resistance performance (effect of suppressing the temperature rise of the steel material in the steel column) is obtained in the cross-sectional portion disclosed in the same document, the volume of the wood-based materials will decrease due to combustion, so it cannot be said that the risk of penetration between upper and lower floors is eliminated.

[0013] This invention was made to solve the aforementioned problems, and aims to provide a wood-covered steel frame and a method for constructing the same, which do not require large joints and do not require much effort to construct. [Means for solving the problem]

[0014] (1) The wood-covered steel frame according to the present invention comprises a wood-covered column member in which a steel column is covered with wood material, and a wood-covered beam member in which a steel beam having an upper flange, a web, and a lower flange is covered with wood material, The steel column has a jointing member provided at the joint surface with the wood-covered beam member, which protrudes toward the wood-covered beam member side. The joining member has two plate-shaped members arranged parallel to each other with a gap corresponding to the thickness of the web of the steel beam, and each plate-shaped member has a joining member through hole in its protruding portion for joining to the wood-covered beam member. In the steel beam, at the end where it is joined to the wood-covered column member, the upper flange and web extend beyond the lower flange, and the extended web portion is provided with a web through-hole for joining to the joining member. The wood material covering the steel beam is provided with a slit open to the lower flange side within the web extension portion into which the joining member can be inserted, and a wood material through-hole is provided at a position opposite to the web through-hole when the joining member is inserted. With the web extension inserted into the gap of the joining member, the wood-covered column member and the wood-covered beam member are joined by pin members inserted into the wood-through hole, the joining member through hole, and the web through hole.

[0015] (2) In addition, in the case described in (1) above, the wood covering of the wood-covered column member is discontinuous in a predetermined range above the joint member, and an inorganic material is provided in the discontinuous portion.

[0016] (3) Furthermore, a method for constructing a wood-covered steel frame as described in (1) or (2) above, With respect to the joining member provided on the wooden material-covered column member, the wooden material-covered beam member is dropped with the open portion of the slit provided in the wooden material-covered beam member aligned, and in a state where the positions of the joining member through-hole and the web through-hole are aligned, the pin member is inserted and joined.

[0017] (4) Also, a wooden material-covered steel frame having a first wooden material-covered beam member obtained by covering a first steel beam with a wooden material, and a second wooden material-covered beam member obtained by covering a second steel beam having an upper flange, a web, and a lower flange with a wooden material, On the joint surface of the first steel beam with the second wooden material-covered beam member, there is a joining member provided so as to protrude toward the second wooden material-covered beam member side. The joining member has two plate-like members arranged in parallel with a gap corresponding to the thickness of the web of the second steel beam, and the plate-like members have one joining member through-hole for joining with the second wooden material-covered beam member at its protruding portion. At the end of the second steel beam joined to the first wooden material-covered beam member, the upper flange and the web are extended more than the lower flange, and one web through-hole for joining with the joining member is provided in the extended web extension portion. In the wooden material covering the second steel beam, within the range of the web extension portion, a slit into which the joining member can be inserted is provided with an opening on the lower flange side, and a wooden material through-hole is provided at a position facing the web through-hole in a state where the joining member is inserted. With the web extension portion inserted into the gap of the joining member, the first wooden material-covered beam member and the second wooden material-covered beam member are joined by pin members inserted into the wooden material through-hole, the joining member through-hole, and the web through-hole.

Effect of the Invention

[0018] The present invention provides a wood-covered steel frame and a method for constructing the same, comprising a wood-covered column member, which is a steel column covered with wood material, and a wood-covered beam member, which is a steel beam having an upper flange, a web, and a lower flange, and is covered with wood material. The steel column has a joining member consisting of two plate-shaped members arranged parallel to the joint surface with the wood-covered beam member, the plate-shaped members have through holes for the joining member, the extended web portion of the steel beam has a web through hole, and the wood material covering the steel beam has a slit that opens towards the lower flange in the range of the web extension portion, and is also provided with a wood through hole. With the web extension portion inserted into the gap of the joining member, the wood-covered column member and the wood-covered beam member are joined by pin members inserted into the wood through hole, the joining member through hole, and the web through hole, thus preventing the joint from becoming large and reducing the effort required for construction. [Brief explanation of the drawing]

[0019] [Figure 1] This is an explanatory diagram of a wood-covered steel frame according to this embodiment, where Figure 1(a) is an external view and Figure 1(b) is a perspective view of Figure 1(a). [Figure 2] Figure 1 is an explanatory diagram of the steel columns used in the wood-covered steel frame and the connecting members attached to the steel columns. [Figure 3] Figure 2 is a side view (Figure 3(a)), and Figure 3(b) is a cross-sectional view taken along arrow AA in Figure 3(a). [Figure 4] Figure 1 shows a side view (Figure 4(a)) of a wood-clad column member used in a wood-clad steel frame, and Figure 4(b) shows a cross-sectional view (Figure 4(b)) taken along the arrow AA in Figure 4(a). [Figure 5] This diagram illustrates the structure of wood-covered column members used in the wood-covered steel frame shown in Figure 1, and is a cross-sectional view CC (Figure 5(a)) and a longitudinal cross-sectional view BB (Figure 5(b)) (Part 1). [Figure 6] This diagram illustrates the structure of wood-clad column members used in the wood-clad steel frame shown in Figure 1, and is a cross-sectional view CC (Figure 6(a)) and a longitudinal cross-sectional view BB (Figure 6(b)) (Part 2). [Figure 7] This diagram illustrates the structure of wood-covered column members used in the wood-covered steel frame shown in Figure 1, and is a cross-sectional view of line CC (Figure 7(a)) and a longitudinal cross-sectional view of line BB (Figure 7(b)) (Part 3). [Figure 8] This is a plan view illustrating the arrangement of the connecting members used in the wood-covered steel frame shown in Figure 1, and the steel beams and wood-covered beam members. [Figure 9] This is a side view illustrating the arrangement relationship between the connecting members used in the wood-covered steel frame shown in Figure 1, and the steel beams and wood-covered beam members. [Figure 10] This is a bottom view illustrating the arrangement of the connecting members used in the wood-covered steel frame shown in Figure 1, and the steel beams and wood-covered beam members. [Figure 11] This is a perspective view (Figure 11(a): external view, Figure 11(b): perspective view) of the wooden material covering the steel beam, viewed from the joint end. [Figure 12] This is a perspective view (Figure 12(a): external view, Figure 12(b): perspective view) of the wooden material covering the steel beam, viewed from the opposite side of the joint end. [Figure 13] This is an explanatory diagram (external view) of the construction method for a steel frame covered with wood. [Figure 14] This is an explanatory diagram (perspective view) of the construction method for a steel frame covered with wood. [Figure 15] This is an explanatory diagram of the construction method for a steel frame covered with wood (with the wood material removed). [Figure 16] This is an explanatory diagram of another embodiment of the wood-covered steel frame according to this embodiment. [Modes for carrying out the invention]

[0020] [Embodiment 1] As shown in Figure 1, the wood-covered steel frame 1 according to this embodiment includes a wood-covered column member 7 in which a steel column 3 is covered with wood material (column-covering wood material 5), and a wood-covered beam member 13 in which a steel beam 9 having an upper flange 9a, a web 9b, and a lower flange 9c is covered with wood material (beam-covering wood material 11). The following describes each component in detail.

[0021] <Steel pillar> Although the steel column 3 shown in Figure 1 has a rectangular cross-section, it can also have an H-shaped, rectangular, or circular cross-section. In the case of a rectangular cross-section, concrete may be filled inside.

[0022] As shown in Figure 2, a joint member 15 is provided at the joint surface of the steel column 3 with the wood-covered beam member 13 so as to protrude toward the wood-covered beam member 13. The joining member 15 has two plate-shaped members arranged parallel to each other with a gap corresponding to the thickness of the web 9b of the steel beam 9, and each plate-shaped member has a joining member through hole 17 into which a pin for joining to the wood-covered beam member 13 is fitted at its protruding portion.

[0023] The spacing between the two plate-like members should take into account the web plate thickness of the steel beam 9, as well as the clearance required during construction. The shape of the protruding part is not specifically defined; it may be rectangular, or the tip may be semicircular. If it is rectangular, the corner of the tip may be chamfered into an arc shape. In addition, in the steel column 3, a diaphragm may be provided as needed to prevent stress transmission between the left and right beams and deformation of the column-beam joint, and the skin plate in that part may be thickened.

[0024] The through-hole 17 of the connecting member may be reinforced with a plate if necessary. The size of the through-hole 17 of the connecting member is determined by considering the shear force acting on that part and the plate thickness of the connecting member 15, but the same calculation is used for the web through-hole 21 provided in the web 9b of the steel beam 9 described later, and the size is adjusted to match the larger diameter.

[0025] Furthermore, if the steel column 3 has an H-shaped cross-section, a connecting member 15 may be provided on the web of the H-shaped steel column. In particular, when the wood covering is arranged in a rectangular shape, it is preferable to place a diaphragm and a skin plate at the joint to form a rectangular cross-section at that part.

[0026] <Wooden material used to cover pillars> The column covering wood material 5, which covers the column, consists of a wood-based plate-like body and, as shown in Figures 4 to 7, is attached to the steel column 3 by mechanical joining or by using a separate base material. The type of plate-like material can be either sawn lumber veneer or laminated timber, and any wood-based material such as CLT or LVL can be arbitrarily selected. The column covering wood material 5 can be continuous across the column members of the upper and lower floors, unless there are specific fire-resistant restrictions.

[0027] As shown in Figure 4(b), the column covering wood material 5 is attached around the entire circumference of the steel column 3, in contact with it, except for the portion of the connecting member 15. Regarding the area where the joint member 15 is attached, as shown in Figure 5, it is also possible to omit the installation of the column covering wood material 5. In this case, in order to ensure fire resistance, inorganic fiber insulation material or mortar may be separately filled into the area where the column covering wood material 5 is not installed.

[0028] The specification shown in Figure 6 is one in which the back surface of the column covering wood material 5 is processed so that the joint member 15 is housed inside the column covering wood material 5. The example shown in Figure 7 is one in which the column covering wood material 5 is placed via a base material 19 such as lightweight steel frame, and the steel column 3 and the column covering wood material 5 are not in contact but are separated. In this specification, instead of the base material 19, a fire-resistant material such as gypsum board or calcium silicate board may be interposed between the column covering wood material 5 and the steel column 3.

[0029] <Steel beam> As shown in Figures 8 to 10, at the end of the steel beam 9 that is joined to the wood-covered column member 7, the upper flange 9a and web 9b extend beyond the lower flange 9c, and a single web through-hole 21 is provided in the extended web portion for joining with the joining member 15. If the beam cross-section is large, the web extension may be cut out on the lower side, as shown in Figure 9(ii). The web through-hole 21 may be reinforced with a plate if necessary. The size of the web through-hole 21 is calculated in the same way as the through-hole of the joint member 15, but as mentioned above, it must be adjusted to match the larger diameter of the pin. Furthermore, the load-bearing capacity of the wood penetration holes 25 in the beam covering wood material 11, which will be described later, does not need to be considered. Furthermore, while the steel beams 9 are arranged along the entire length, if they are replacing wooden beams, they may be placed only near the joints at both ends.

[0030] <Wooden material used to cover beams> As shown in Figures 11 and 12, the beam covering wood material 11 that covers the beam has a slit 23 in the web extension portion that is open to the lower flange 9c side into which a joining member 15 can be inserted, and a wood material through hole 25 is provided at a position opposite to the web through hole 21 when the joining member 15 is inserted. As shown in Figure 9, the height of the slit 23 is aligned with the upper end position and depth of the joining member 15. Furthermore, the size of the wood through-hole 25 is the same as the diameter of the joint member through-hole 17 and the web through-hole 21.

[0031] The beam covering wood material 11 consists of wood-based plate-like bodies or square timbers, and is attached to the steel beam 9 by mechanical joining or by using a separate base material. As for the method of attaching the beam covering wood material 11, it may be attached in advance to the area enclosed by the upper and lower flanges 9a, 9c and the web 9b, and the beam covering wood material 11 may be attached so as to cover the ends of the upper and lower flanges 9a, 9c, or any attachment method can be selected, such as cutting out the part that will be included in the flanges in advance and fitting it in.

[0032] The thickness of the beam covering wood material 11 at the ends of the upper and lower flanges 9a and 9c, and on the underside of the lower flange 9c, should be determined by considering the presence or absence of a composite effect, or by considering the burn allowance in the event of a fire. Furthermore, gypsum board, calcium silicate board, or other fire-resistant material may be interposed between the steel beam 9 and the beam covering wood material 11. In this case, that portion can serve as a fire-stopping layer. The type of plate-like material can be either sawn lumber veneer or laminated timber, and any wood-based material such as CLT or LVL can be arbitrarily selected.

[0033] <Construction method for wood-clad steel frames> A method for constructing a wood-covered steel frame 1 by joining wood-covered column members 7 and wood-covered beam members 13 will be explained with reference to Figures 13 to 15. As shown in Figures 13 to 15, the joint member 15 protruding from the column covering wood material 5 of the wood-covered column member 7 is aligned with the slit 23 provided in the beam covering wood material 11, and the wood-covered beam member 13 is dropped in from above. To facilitate understanding of the relationship between the wood-covered column member 7 and the wood-covered beam member 13, Figure 14 shows the column-covered wood material 5 and beam-covered wood material 11 in a transparent view, showing only their outlines, while Figure 15 excludes the column-covered wood material 5 and beam-covered wood material 11.

[0034] As mentioned above, the height of the slit 23 is aligned with the upper end position and depth of the joint member 15 (see Figure 9), so at this stage, the positions of the joint member through hole 17, the web through hole 21, and the wood material through hole 25 coincide. Then, the wood-covered column member 7 and the wood-covered beam member 13 are joined by inserting the pin member 26 through the wood-covered hole 25. The length of the pin member 26 may be the same as the total width of the wood-covered beam member 13, or it may be shorter than the total width of the wood-covered beam member 13, with both ends closed off with wooden plugs or the like.

[0035] Through the above joining method, the wood-covered column member 7 and the wood-covered beam member 13 are joined by pin members 26 inserted into the wood-through holes 25, the joining member through holes 17, and the web through holes 21, with the web extension portion inserted into the gap of the joining member 15. This results in a wood-covered steel frame 1.

[0036] As described above, in the wood-covered steel frame 1 of this embodiment, the wood covering can be done in advance at a factory or the like, rather than on-site, and the joints do not become larger as they would be when constructed on-site. Furthermore, since the beam covering wood material 11 is provided with a slit 23 that opens on the lower flange 9c side into which the connecting member 15 can be inserted, the attachment of the wood covering beam member 13 to the wood covering column member 7 can be done by dropping it in from above, which reduces the effort required for construction. Furthermore, since the web extension is inserted into the gap of the joint member 15, and the pin members 26 are inserted into the wood material through-hole 25, the joint member through-hole 17, and the web through-hole 21 to join them, the joint after the wood material-covered beam member 13 is attached does not use a splice plate, so there is no need to separately attach a considerable area of ​​wood, and it is also aesthetically superior because a large number of drift pins are not driven in.

[0037] [Embodiment 2] In Embodiment 1, an example was shown where the column covering wood material 5 was continuous from floor to floor. However, if fire resistance is required, as shown in Figure 16, the column covering wood material 5 can be made discontinuous in an area equivalent to the thickness of the fire-resistant floor 27 (for example, a concrete floor) placed above it, and fire-resistant material 29 can be placed in that area. This prevents the fire from spreading to the upper and lower floors even if the wooden cladding material 5 on the columns is destroyed by fire.

[0038] As for the fire-resistant material 29, it may be a plate-shaped material such as gypsum board or calcium silicate board, or a fibrous material such as ceramic fiber, alkali earth silicate, or heat-resistant rock wool, or an amorphous material such as mortar, gypsum, sodium silicate filler, or sprayed rock wool, which is then hardened and used. These materials can be selected according to the required fire resistance performance and may be used individually or in combination.

[0039] In the embodiments 1 and 2 described above, the wood-covered steel frame 1 was described as a wood-covered steel frame having columns and beams, i.e., wood-covered column members 7 and wood-covered beam members 13. However, the present invention also includes a wood-clad steel frame formed by joining beams together, in which case it has the following configuration.

[0040] A wood-covered steel frame comprising a first wood-covered beam member, which is a first steel beam covered with wood material, and a second wood-covered beam member, which is a second steel beam having an upper flange, a web, and a lower flange, which is covered with wood material, The first steel beam has a jointing member provided at the joint surface with the second wood-covered beam member so as to protrude toward the second wood-covered beam member, The joining member has two plate-like members arranged parallel to each other with a gap corresponding to the thickness of the web of the second steel beam, and each plate-like member has a joining member through hole in its protruding portion for joining to the second wood-covered beam member. In the second steel beam, at the end where it is joined to the first wood-covered beam member, the upper flange and web extend beyond the lower flange, and the extended web portion is provided with a web through-hole for joining to the joining member. The wood material covering the second steel beam is provided with a slit open to the lower flange side within the web extension portion into which the joining member can be inserted, and a wood material through-hole is provided at a position opposite to the web through-hole when the joining member is inserted. A wood-covered steel frame in which the first wood-covered beam member and the second wood-covered beam member are joined by pin members inserted into the wood-covered through-hole, the joining member through-hole, and the web through-hole, with the web extension inserted into the gap of the joining member. [Examples]

[0041] We have confirmed through a trial design whether the wood-covered steel frame 1 according to the present invention is actually feasible, and will explain below. Table 1 shows an example of structural design for the steel beam 9 and the pin members 26 that connect the column and beam in this construction method.

[0042] [Table 1]

[0043] In conventional steel frame construction, the column-beam joint typically involves welding the upper and lower flanges to the column's diaphragm and welding the web to the column's outer surface. From a structural mechanics perspective, this is often designed as a fixed-end beam. In contrast, the shape of the column-beam joint in this construction method is such that the web 9b of the beam is joined to a joint member 15 consisting of two plate-shaped members provided on the steel column 3 via a pin member 26 (see Figure 1), and structurally it is designed as a beam with pin members 26 at both ends. This design example is a redesign of the main beam in the original design, which was calculated as a beam with fixed ends, by changing it to a beam with pins at both ends.

[0044] The building used in this design is a four-story steel-framed office building. This design example focuses on the main beams from the second floor to the roof (R) floor. The main beams are classified into four types, from Beam 1 to Beam 4, on each floor. The span and load-bearing width are as shown in Table 1. The beam could be a hybrid member with a steel beam covered in wood, where both the steel and wood bear the stress. However, for simplicity, this design example assumes that all stress is borne by the steel (steel beam), as in the original design.

[0045] Regarding the loads, the main beams in the original design bear their own weight, live loads, and short-term loads due to earthquakes and wind, but the main beams in this construction method do not bear short-term loads, bearing only their own weight and live loads, with short-term loads being borne by braces placed separately. Verification was performed for bending stress and deflection. The shape was H-shaped steel, and the steel grade was 325 N / mm2.

[0046] As a result, for example, the cross-section of the main beam 1 on the second floor, which was H-650×250×12×25 in the original design, became H-600×250×12×28 when both ends were pinned. In terms of cross-sectional area, this construction method was 1.04 times that of the original design. Overall, in many cases the cross-section was smaller with this construction method than with the original design, and the average ratio of the cross-sectional areas of all main beams was 0.99. From this, it can be seen that there is not much difference in the cross-sectional area of ​​the main beams between the original design and this construction method. Generally, beams with fixed ends are more structurally efficient and often have a smaller cross-section than beams with pins at both ends. However, this construction method allows for a cross-section equivalent to that of a beam with fixed ends by having the braces bear the short-term load.

[0047] Next, the joints were designed for the main beams that had been designed as described above. The joint in question here consists of a pin member 26 and a joint member 15 (plate-shaped member) that receives the pin member 26. The steel grade of the pin member 26 and the plate-shaped member is 325 N / mm². 2 Grade steel was used. Regarding the design concept, it was assumed that the pin member 26 and the plate-like member transmit the shear force of the main beam to the column, and their respective cross-sectional areas were calculated to correspond to the cross-sectional area of ​​the main beam's web. The calculation also confirmed that the hole through which the pin member 26 penetrates the plate-like member would not undergo pull-out failure.

[0048] As a result, the largest diameter of the pin member 26 is 140 mm, and the largest thickness of the plate-like member is 22 mm, allowing the joining member 15 to be made thinner. Here, we have shown the results of a study in which the main beam web and connecting member 15 were not particularly reinforced. However, by reinforcing the area around the through-hole with a backing plate, it becomes possible to make the connecting member 15 thinner, or by increasing the strength of the pin member 26 at the same time, the diameter of the pin member 26 can be reduced.

[0049] From the above, it was found that this construction method is fully feasible from a design perspective and is useful as a hybrid material of steel and wood. [Explanation of symbols]

[0050] 1 Wood-coated steel frame 3 steel columns 5. Wooden cladding for pillars 7. Wood-covered column members 9 Steel beam 9a Upper flange 9b Web 9c lower flange 11. Beam cladding wood 13 Wooden covered beam members 15 Joining members 17 Joint member through hole 19. Substrate 21 Web through-holes 23 slits 25 Wood material through hole 26 Pin component 27 floors 29 Fireproof materials

Claims

1. A wood-covered steel frame comprising wood-covered column members, which are steel columns covered with wood-based material, and wood-covered beam members, which are steel beams having an upper flange, a web, and a lower flange, covered with wood-based material, The steel column has a jointing member provided at the joint surface with the wood-covered beam member, which protrudes toward the wood-covered beam member side. The joining member has two plate-shaped members arranged parallel to each other with a gap corresponding to the thickness of the web of the steel beam, and each plate-shaped member has a joining member through hole in its protruding portion for joining to the wood-covered beam member. In the steel beam, at the end where it is joined to the wood-covered column member, the upper flange and web extend beyond the lower flange, and the extended web portion is provided with a web through-hole for joining to the joining member. The wood material covering the steel beam is provided with a slit open to the lower flange side within the web extension portion into which the joining member can be inserted, and a wood material through-hole is provided at a position opposite to the web through-hole when the joining member is inserted. A wood-covered steel frame in which the wood-covered column member and the wood-covered beam member are joined by pin members inserted into the wood-covered through-hole, the joining member through-hole, and the web through-hole, with the web extension inserted into the gap of the joining member.

2. The wood-covered steel frame according to claim 1, characterized in that the wood-covered column member is discontinuous in a predetermined range above the joint member, and an inorganic material is provided in the discontinuous portion.

3. A method for constructing a wood-covered steel frame according to claim 1 or 2, A method for constructing a wood-covered steel frame, characterized in that the wooden-covered beam member is dropped into the wood-covered column member by aligning the opening of the slit provided in the wooden-covered beam member with the joint member provided in the wooden-covered column member, and the pin member is inserted and joined while the positions of the joint member through hole and the web through hole are aligned.

4. A wood-covered steel frame comprising a first wood-covered beam member, which is a first steel beam covered with wood material, and a second wood-covered beam member, which is a second steel beam having an upper flange, a web, and a lower flange, which is covered with wood material, The first steel beam has a jointing member provided at the joint surface with the second wood-covered beam member so as to protrude toward the second wood-covered beam member, The joining member has two plate-like members arranged parallel to each other with a gap corresponding to the thickness of the web of the second steel beam, and each plate-like member has a joining member through hole in its protruding portion for joining to the second wood-covered beam member. In the second steel beam, at the end where it is joined to the first wood-covered beam member, the upper flange and web extend beyond the lower flange, and the extended web portion is provided with a web through-hole for joining with the joining member. The wood material covering the second steel beam is provided with a slit open to the lower flange side within the web extension portion into which the joining member can be inserted, and a wood material through-hole is provided at a position opposite to the web through-hole when the joining member is inserted. A wood-covered steel frame in which the first wood-covered beam member and the second wood-covered beam member are joined by pin members inserted into the wood-covered through-hole, the joining member through-hole, and the web through-hole, with the web extension inserted into the gap of the joining member.

Images