Hybrid member, and column-beam structure using the hybrid member

Abstract

To provide a hybrid member easy to construct, suppressed in cost, and capable of efficiently transmitting stress from a steel material to wood, and a column-beam frame using the hybrid member.SOLUTION: A hybrid member 1A is formed by jointing a steel material to wood, and has a steel material part 2 having a flat plate part 22 extended in the material axis direction, a wood part 3 placed side by side with the flat plate part 22, and a steel plate 4 jointed to the flat plate part 22, and fitted to a surface of the wood part 3 by structural machine screws 7. The steel plate 4 is tightened to the flat plate part 22 by a high-strength bolt 5, and the wood part 3 is jointed to the steel material part 2.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a hybrid member formed by joining steel materials and wood, and a column-beam structure using the hybrid member.

Background Art

[0002] In the frameworks of various building structures, hybrid structural materials combining a central steel material made of steel frames and wooden members are used. For example, Patent Document 1 discloses a configuration including a steel frame member having upper and lower flanges and a web, and a wooden member disposed so as to close the space between the upper and lower flanges at a position spaced from the web. In this configuration, the steel frame member and the wooden member are integrally fixed by a connecting member whose tip side is screwed and inserted into the wooden member through a through hole provided in the flange. In the configuration disclosed in Patent Document 1, in order to reduce the quantity of the wooden members used, the wooden members are provided at intervals from the web and are not joined to the web. For this reason, the stress transmission from the steel material to the wood may not be efficiently performed.

[0003] Further, Patent Document 2 discloses a configuration including a central steel material made of steel frames, a wooden member provided along the central steel material, a pressure receiving member that joins the wooden member to the central steel material, and a joining member that extends in the major axis direction of the central steel material, has one end fixed to the wooden member, and the other end fixed to the pressure receiving member to join the pressure receiving member and the wooden member. The central steel material includes side plates provided at intervals from the side surface of the web constituting the central steel material. The wooden member is provided on the side plates, and the pressure receiving member is joined to the side plates. In the configuration disclosed in Patent Document 2, it is necessary to join the wooden member to the web via members such as the pressure receiving member and the side plates, which is time-consuming in construction and increases the cost as the number of parts increases.

[0004] In addition, Patent Document 3 discloses a configuration including a steel member, a plurality of wooden members fixed to the steel member with fastening bolts, shear members disposed in through holes formed in each wooden member, a pressing member disposed in contact with the steel member and outside the shear member disposed in the through hole, and the shear member is pressure-bonded and frictionally joined to the steel member by the tightening force of the fastening bolts inserted through the bolt insertion holes of the steel member, the shear member, and the pressing member, and the pressing member is used to prevent the wooden member from coming off. In the configuration disclosed in Patent Document 3, since it is necessary to use a special joining metal (shear member), the cost increases. In addition, the shear member has to be driven into a through hole having the same inner diameter as the outer diameter of the shear member, and the workability is poor.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0006] The problem to be solved by the present invention is to provide a hybrid member and a column-beam structure using the hybrid member that are easy to construct, can suppress costs, and can efficiently transmit stress from steel to wood.

Means for Solving the Problems

[0007] In order to solve the above problems, the present invention employs the following means. That is, the hybrid member of the present invention is a hybrid member formed by joining a steel material and wood, comprising a steel material part having a flat plate part extending in the material axis direction, a wood part provided along with the flat plate part, and a steel plate attached to the surface of the wood part joined to the flat plate part by structural screws, wherein the steel plate is fastened to the flat plate part with high-strength bolts, and the wood part and the steel material part are joined. According to such a configuration, a steel plate attached to the wood part by structural screws is joined to the flat plate part of the steel material part, whereby a hybrid member in which the steel material part and the wood part are integrated can be constituted. In addition, the steel plate attached to the wood part is fastened to the flat plate part of the steel material part with high-strength bolts, so that the wood part and the steel material part are joined. Further, the steel plate is joined to the wood part by structural screws. Therefore, a special joining alloy is not required for joining the wood part and the steel material part, and the construction cost can be suppressed. Also, in construction, the steel plate attached to the wood part and the flat plate part of the steel material part may be joined with high-strength bolts, so the construction is easy and the management of the tightening force of the high-strength bolts is also easy. Thus, since the steel plate attached to the wood part is friction-joined to the steel material part with high-strength bolts, the axial force acting on the steel material part is efficiently transmitted to the wood part via the steel plate and the structural screws. Therefore, part of the axial force acting on the steel material part is borne by the wood part, and the axial rigidity of the entire hybrid member can be improved. In this way, it is possible to provide a hybrid member that is easy to construct, can suppress costs, and can efficiently transmit stress from steel to wood.

[0008] In one aspect of the present invention, the wood part is disposed on both sides of the flat plate part. According to such a configuration, by arranging the xylem on both sides of the flat plate portion of the steel member, the steel member can be efficiently stiffened by the xylem and buckling reinforcement can be achieved. Further, since the steel member is at least partially fire-resistant coated by the xylem arranged on both sides of the flat plate portion, a hybrid member excellent in fire resistance performance can be realized.

[0009] In one aspect of the present invention, in the xylem, through holes are formed in a direction perpendicular to the flat plate portion at positions where the high-strength bolts are arranged, the high-strength bolts are provided in the through holes, and the outside of the through holes is blocked by a plugging material. According to such a configuration, the high-strength bolts for joining the steel member and the xylem are arranged in the through holes formed in the xylem, and the through holes are blocked by a plugging material. Thereby, it is possible to suppress the exposure of the high-strength bolts to the outside. Therefore, the appearance of the hybrid member can be enhanced. Further, the high-strength bolts do not directly contact the outside air, and it is possible to suppress rust.

[0010] The present invention also provides a column-beam structure using a hybrid member, which includes a steel column and a beam installed between the columns, and the beam is formed of the hybrid member as described above. According to such a configuration, by using the hybrid member as described above, construction is easy and costs can be suppressed. Further, in the beam, by using the hybrid member, a structure capable of efficiently transmitting stress from steel to wood can be achieved.

Effects of the Invention

[0011] According to the present invention, it is possible to provide a hybrid member and a column-beam structure using the hybrid member that are easy to construct, can suppress costs, and can efficiently transmit stress from steel to wood.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

Figure 19

Embodiment for Carrying Out the Invention

[0013] Hereinafter, with reference to the accompanying drawings, embodiments for implementing the hybrid member according to the present invention will be described based on the drawings. A side view showing a part of the hybrid member according to an embodiment of the present invention is shown in FIG. 1. FIG. 2 is a plan view of the hybrid member of FIG. 1. The hybrid member 1A according to the present embodiment is used as a beam constituting the frame of the structure, as will be described later. The hybrid member 1A may be used as another member such as a column. The hybrid member 1A is formed by joining a steel member 2 made of steel and a wooden member 3 made of wood. The hybrid member 1A mainly includes a steel member 2, a wooden member 3, a steel plate 4, and high-strength bolts 5.

[0014] The steel member 2 is made of a long-shaped steel section. FIG. 3 is a cross-sectional view of the portion of the hybrid member that does not include the steel plate in the A-A portion of FIGS. 1 and 2. FIG. 4 is a cross-sectional view of the portion of the hybrid member that includes the steel plate in the B-B portion of FIGS. 1 and 2. In the present embodiment, the steel member 2 has a substantially T-shaped cross-section that intersects the material axis direction Da, which is the direction in which the steel member 2 and the hybrid member 1A extend. The steel member 2 integrally includes a flange portion 21 and a flat plate portion 22 that forms a web portion provided below the flange portion 21. As shown in FIG. 2, the flange portion 21 has a rectangular shape extending in the material axis direction Da when viewed from above. As shown in FIGS. 3 and 4, when viewed from the material axis direction Da, the flat plate portion 22 extends downward from the central portion of the flange portion 21 in the width direction Dw that is orthogonal to the material axis direction Da within the plane formed by the flange portion 21. As shown in FIG. 1, when viewed from the width direction Dw, the flat plate portion 22 has a rectangular shape extending in the material axis direction Da. Note that the steel member portion 2 may be made of shaped steel having other cross-sectional shapes such as flat plates and H-shaped cross-sections, not limited to T-shaped steel.

[0015] The wooden portion 3 is provided so as to extend in the material axis direction Da and be provided adjacent to the flat plate portion 22 at a position facing the surface 22f facing the width direction Dw of the flat plate portion 22. In the present embodiment, the wooden portion 3 is disposed on both sides of the flat plate portion 22 in the width direction Dw. The wooden portion 3 may be provided only on one side of the flat plate portion 22 in the width direction Dw. As viewed from the material axis direction Da as shown in FIGS. 3 and 4, the wooden portion 3 has a rectangular cross-sectional shape. The wooden portion 3 has an inner surface 3f facing the surface 22f side of the flat plate portion 22, an outer surface 3g facing the side opposite to the surface 22f, an upper surface 3t, and a lower surface 3b. The outer surface 3g of the wooden portion 3 is disposed, for example, inside the width direction Dw rather than the end portion 21s in the width direction Dw of the flange portion 21. The upper surface 3t of the wooden portion 3 is provided at a distance downward from the lower surface of the flange portion 21. Thereby, a gap S1 is provided between the upper surface 3t of the wooden portion 3 and the lower surface of the flange portion 21. A steel plate 4, which will be described later, is partially attached to the inner surface 3f of the wooden portion 3. Thus, a gap S2 is provided between the surface 22f of the flat plate portion 22 and the surface 3f at a portion where the steel plate 4 is not attached. The lower surface 3b of the wooden portion 3 is disposed, for example, below the lower end 22b of the flat plate portion 22. For the wooden portion 3, it is preferable to use, for example, sawn timber, glued laminated timber (LVL: Laminated Veneer Lumber), cross-laminated timber (Cross Laminated Timber), or other engineered wood products having the required strength as a structural material. A plurality of through holes 32 are formed in the wooden portion 3 at predetermined intervals in the material axis direction Da. Each through hole 32 is formed to penetrate the wooden portion 3 in a direction (width direction Dw) perpendicular to the flat plate portion 22. In the present embodiment, each through hole 32 is formed in the middle portion of the wooden portion 3 in the vertical direction Dv perpendicular to each of the material axis direction Da and the width direction Dw.

[0016] FIG. 5 is a front view showing a steel plate provided in the hybrid member of FIG. 4. FIG. 6 is a cross-sectional view of the steel plate. The steel plate 4 is joined to the inner surface 3f located on the flat plate portion 22 side of the wooden portion 3. A plurality of steel plates 4 are provided at predetermined intervals in the material axis direction Da. As shown in FIG. 5, the steel plate 4 is formed from a rectangular steel plate. As shown in FIGS. 4, 5, and 6, bolt insertion holes 4h and a plurality of screw holes 4g are formed in the steel plate 4. The bolt insertion holes 4h and the plurality of screw holes 4g are each formed to penetrate the steel plate 4 in the plate thickness direction (width direction Dw). In the present embodiment, the bolt insertion holes 4h are formed at the center of the steel plate 4. A plurality of screw holes 4g are formed around the bolt insertion holes 4h in the steel plate 4 at intervals in the material axis direction Da and the vertical direction Dv. As shown in FIG. 4, each steel plate 4 is attached to the inner surface 3f of the wooden portion 3 that is joined to the flat plate portion 22 by a plurality of structural screws 7. Each structural screw 7 is screwed into the wooden portion 3 through each screw hole 4g. As shown in FIGS. 5 and 6, around each screw hole 4g on the surface of the steel plate 4, a counterbore (drilling) 4k for accommodating the head of the structural screw 7 is provided so as to be recessed from the surface.

[0017] The steel plate 4 is fastened to the surface 22f of the flat plate portion 22 by high-strength bolts 5. In the present embodiment, the wooden portions 3 arranged on both sides in the width direction Dw with the flat plate portion 22 interposed therebetween are joined to the flat plate portion 22 by the steel plates 4 joined to each other being fastened to the flat plate portion 22 by high-strength bolts 5. The high-strength bolts 5 are arranged in through holes 32 formed in the wooden portions 3 on both sides in the width direction Dw. The high-strength bolts 5 are fastened and fixed through bolt insertion holes 4h formed in the steel plates 4 on both sides in the width direction Dw and through holes 22h formed in the flat plate portion 22. The steel plate 4 is provided such that the plate surface 4f facing the flat plate portion 22 abuts against the surface 22f of the flat plate portion 22. By fastening the steel plate 4 to the flat plate portion 22 with high-strength bolts 5, the steel plate 4 is frictionally joined to the flat plate portion 22 and functions as a stress transmission member that transmits the stress acting on the steel portion 2 to the wooden portion 3. Here, in order to ensure the required friction coefficient between the plate surface 4f and the surface 22f of the steel plate 4, shot blasting or the like is performed on at least one of the plate surface 4f and the surface 22f to form fine irregularities. Further, the high-strength bolts 5 are fastened with a predetermined tightening torque using a torque wrench in order to appropriately control the frictional force generated between the steel plate 4 and the flat plate portion 22. Since the head of the structural screw 7 is accommodated in the counterbore 4k provided around each screw hole 4g on the surface of the steel plate 4 as described above, the head of the structural screw 7 does not protrude from the surface of the steel plate 4. Therefore, even if the steel plate 4 is attached to the wooden portion 3 with the structural screws 7, the structural screws 7 are configured not to interfere with the frictional joining between the steel plate 4 and the flat plate portion 22. In this way, the wooden portions 3 arranged on both sides of the flat plate portion 22 in the width direction Dw are joined to the flat plate portion 22 of the steel portion 2 via the structural screws 7, the steel plates 4, and the high-strength bolts 5. The through holes 32 of each xylem 3 are closed by a plugging material 35 at the opening facing the outside, which is opposite to the flat plate portion 22. That is, the outside of the through hole 32 is closed by the plugging material 35. The plugging material 35 is formed of the same material as the xylem 3 and is fixed to the through hole 32 by an adhesive or the like. As a result, a cavity S3 is formed inside the through hole 32, which is closed on the inner side by the steel plate 4 and high-strength bolts 5 and on the outer side by the plugging material 35, respectively.

[0018] When assembling such a hybrid member 1A, the steel plate 4 is previously joined to the surface 3f of the xylem 3 by structural screws 7. Thereafter, the xylem 3 to which the steel plate 4 is joined is arranged on both sides of the flat plate portion 22 of the steel member 2 in the width direction Dw, and the steel plate 4 is fastened to the flat plate portion 22 by high-strength bolts 5 within the through hole 32. Thereafter, the through hole 32 is closed by the plugging material 35. In this way, the hybrid member 1A as described above can be assembled.

[0019] Next, a column-beam structure using the hybrid member 1A as described above will be described with reference to FIG. 1 and FIGS. 7 to 11. FIG. 7 is a perspective view showing a column-beam structure using the hybrid member 1A. FIG. 8 is a perspective view of the column-beam structure in FIG. 7 viewed from another direction. FIG. 9 is an enlarged view of the portion viewed in the direction of arrow C in FIG. 8. FIG. 10 is a bottom view of the portion viewed in the direction of arrow D in FIG. 7 looking down from above. FIG. 11 is a bottom view of the portion viewed in the direction of arrow E in FIG. 7 looking down from above, and shows the fit of the end portion of the column-beam structure. The column-beam structure 40 includes columns 41, roof beams 42 constituting a roof, and a beam 43 provided below the roof beams 42. The columns 41 are made of steel. In the present embodiment, the columns 41 are steel pipes. The roof beams 42 are installed between the columns 41 at the top of the columns 41. The beam 43 is installed between the columns 41 below the roof beams 42 and is provided at the lowermost position in the internal space of the building realized inside the column-beam structure 40. In the present embodiment, the beam 43 provided below is formed by the hybrid member 1A as described above. As shown in FIG. 11, on the column 41, brackets 47 formed in a V shape in plan view are provided so as to be gradually spaced apart in the horizontal plane as they move away from the column 41. Different beams 43 are joined to each of the two ends of the brackets 47 provided in such a spaced-apart manner. In this way, in the present embodiment, the beams 43 are provided such that four beams form a single rhombus shape in plan view.

[0020] The ends of the beam 43 that are not joined to the column 41 are joined to each other at an angle with other beams 43 via, for example, brackets (not shown). At the joint of the beams 43, the beams 43 are suspended from the roof beam 42 by the bundled member 44 and the lattice member 45. As shown in FIG. 1, a bracket 46 is joined to the upper surface of the flange portion 21 of the hybrid member 1A that constitutes the beam 43. The bundled member 44 is provided to extend in the vertical direction, with its upper end joined to the roof beam 42 and its lower end joined to the bracket 46. The lattice member 45 is provided to be inclined obliquely with respect to the vertical direction, with its upper end joined to the roof beam 42 and its lower end joined to the bracket 46. A plurality of lattice members 45 are provided around the bundled member 44. For example, in FIG. 9, three lattice members 45 are provided for one bundled member 44. Each of the plurality of lattice members 45 provided for one bundled member 44 is provided such that its upper end is spaced apart from the bundled member 44 and gradually approaches the bundled member 44 as it goes downward. As shown in FIG. 1, in the hybrid member 1A, the steel member portion 2 is provided to protrude in the axial direction Da from the end of the wooden member portion 3. A gusset plate 49 is joined to the steel member portion 2 so as to be orthogonal to each of the flat plate portion 22 and the upper flange 21 and along the end face of the wooden member portion 3. The gusset plate 49 enables more efficient transmission of the axial force between the steel member portion 2 and the wooden member portion 3. A reinforcing steel plate 48 is joined to the bracket 46 at a position above the gusset plate 49 so that the gusset plate 49 extends upward.

[0021] According to the hybrid member as described above, there is a hybrid member 1A formed by joining steel and wood, which includes a steel member 2 having a flat plate portion 22 extending in the material axis direction Da, a wood portion 3 provided beside the flat plate portion 22, and a steel plate 4 attached to the surface 3f of the wood portion 3 and joined to the flat plate portion 22 by structural screws 7. The steel plate 4 is fastened to the flat plate portion 22 by high-strength bolts 5, and the wood portion 3 and the steel member 2 are joined together. According to such a configuration, the wood portion 3, the steel plate 4 attached by the structural screws 7, and the flat plate portion 22 of the steel member 2 are joined together, thereby forming a wood-steel hybrid member 1A in which the steel member 2 and the wood portion 3 are integrated. In addition, the steel plate 4 attached to the wood portion 3 is fastened to the flat plate portion 22 of the steel member 2 by high-strength bolts 5, so that the wood portion 3 and the steel member 2 are joined together. Furthermore, the steel plate 4 is joined to the wood portion 3 by structural screws 7. Therefore, no special joining alloy is required for joining the wood portion 3 and the steel member 2, and the construction cost can be suppressed. Also, during construction, the steel plate 4 attached to the wood portion 3 and the flat plate portion 22 of the steel member 2 may be joined by high-strength bolts 5, so the construction is easy and the management of the tightening force of the high-strength bolts 5 is also easy. In this way, the steel plate 4 attached to the wood portion 3 is frictionally joined to the steel member 2 by high-strength bolts 5, so the axial force acting on the steel member 2 is efficiently transmitted to the wood portion 3 via the steel plate 4 and the structural screws 7. Therefore, a part of the axial force acting on the steel member 2 is borne by the wood portion 3, and the axial rigidity of the entire hybrid member 1A can be improved. In this way, it is possible to provide a hybrid member 1A that is easy to construct, can suppress costs, and can efficiently transmit stress from steel to wood.

[0022] In this embodiment, more specifically, the axial force is transmitted from the steel member part 2 to the steel plate 4 by friction joining, and further, the axial force is transmitted from the steel plate 4 to the wooden member part 3 through the shear of the structural screws 7, so that part of the axial force can be borne by the wooden member part 3. As a result, the axial rigidity of the entire hybrid member 1A can be improved, and the deflection due to the dead weight and loading of the hybrid member 1A and the vibration due to seismic load and wind load can be suppressed. This share of the axial force borne by the wooden member part 3 can be adjusted by changing the type and number of the structural screws 7. Therefore, excessive axial force transmission to the wooden member part 3, which is relatively inferior in structural performance compared to the steel member part 2, can be suppressed.

[0023] Also, the wooden member part 3 is disposed on both sides of the flat plate part 22. According to such a configuration, since the wooden member part 3 is disposed on both sides of the flat plate part 22 of the steel member part 2, the steel member part 2 can be efficiently stiffened by the wooden member part 3 while buckling reinforcement is performed. Further, since the steel member part 2 is at least partially fireproofed by the wooden member parts 3 disposed on both sides of the flat plate part 22, a hybrid member 1A excellent in fireproof performance can be realized.

[0024] In particular, in this embodiment, a T-shaped steel is used as the steel member part 2 with the flange part 21 positioned upward, and the wooden member part 3 is disposed on both sides of the flat plate part 22. For this reason, when the hybrid member 1A is used as a beam, when the hybrid member 1A is looked up from below, a natural interior can be achieved as the representation of the wood. In the above embodiment, although it has been described that the steel member part 2 is not limited to a T-shaped steel and may be a flat plate, particularly when a flat plate is used, the flat plate is likely to buckle when receiving a compressive axial force. By disposing the wooden member part 3 on both sides of the flat plate part 22 (i.e., the flat plate itself), the effect of buckling stiffening by the wooden member part 3 becomes large, and the compressive strength of the member can be significantly improved.

[0025] Further, in the xylem 3, a through-hole 32 is formed in a direction orthogonal to the flat plate portion 22 at a position where the high-strength bolt 5 is disposed. The high-strength bolt 5 is provided in the through-hole 32, and the outside of the through-hole 32 is blocked by a plugging material 35. According to such a configuration, the high-strength bolt 5 that joins the steel member portion 2 and the xylem portion 3 is disposed in the through-hole 32 formed in the xylem portion 3, and the through-hole 32 is blocked by the plugging material 35. Thereby, it is possible to suppress the high-strength bolt 5 from being exposed to the outside. Therefore, the appearance of the hybrid member 1A can be enhanced. Further, the high-strength bolt 5 does not directly contact the outside air, and rust can be suppressed.

[0026] Further, the column-beam structure 40 of the present embodiment includes a steel column 41 and a beam 43 installed between the columns 41, and the beam 43 is formed by the hybrid member 1A as described above. According to such a configuration, by using the hybrid member 1A as described above, construction is easy and costs can be suppressed. Further, in the beam 43, by using the hybrid member 1A, a structure capable of efficiently transmitting stress from steel to wood can be achieved.

[0027] (First Modification of the Embodiment) Note that the hybrid member of the present invention is not limited to the above-described embodiment described with reference to the drawings, and various modifications can be considered within its technical scope. For example, in the above embodiment, the steel plate 4 is fastened to the flat plate portion 22 of the steel member portion 2 by one high-strength bolt 5, but the number of high-strength bolts 5 can be appropriately changed. For example, as in the hybrid member 1B shown in FIG. 12, the steel plate 4 may be fastened to the flat plate portion 22 of the steel member portion 2 by two high-strength bolts 5 arranged at intervals in the vertical direction Dv. In this first modification example, further, a lower closing member 50 is provided between the lower ends of the wooden parts 3 sandwiching the steel material plate 4 constituting the hybrid member 1B. By providing the lower closing member 50, when looking up at the hybrid member 1B from below, the steel material plate 4 is hidden, so that a hybrid member 1B entirely covered with wood can be realized. One side surface 50a of the lower closing member 50 in the width direction Dw is fixed to the wooden part 3 with an adhesive or the like. The other side surface 50b of the lower closing member 50 in the width direction Dw is in contact with the wooden part 3 but not joined. Since the side surface 50b of the lower closing member 50 is not joined to the wooden part 3, when deformation occurs in the hybrid member 1B, the influence of the deformation acting on each wooden part 3 sandwiching the steel material plate 4 on the other wooden parts 3 can be suppressed.

[0028] (Second Modification Example of the Embodiment) In the hybrid member 1C of the second modification example shown in FIG. 13, in addition to the configuration of the hybrid member 1A shown in the above embodiment, the flange portion 21 of the steel material portion 2 and the wooden part 3 are joined by long screws 8. A plurality of long screws 8 are provided at predetermined intervals in the material axis direction Da to join the flange portion 21 and the wooden part 3.

[0029] (Third Modification Example of the Embodiment) In the hybrid member 1D of the third modification example shown in FIG. 14, in addition to the configuration of the hybrid member 1B shown in FIG. 12, a PC steel material 9 is provided on the lower side of the wooden part 3. The PC steel material 9 extends in the material axis direction Da, and a predetermined tensile force is introduced and fixed in a state where the wooden part 3 is sandwiched by fixing tools (not shown) at both ends of the material. As shown in FIG. 14, the PC steel material 9 is eccentrically arranged with respect to the centroid of the cross section of the wooden part 3 to introduce a tensile force, so that the cross section of the wooden part 3 is not uniform, and a high compressive stress state is formed on the lower end side to resist the tensile force applied to the wooden part 3. As a result, compressive prestress is introduced into the cross section of the wooden part 3 as a reaction force of the tensile force acting on the PC steel material 9, so that the tensile strength of the wooden part 3 is apparently increased, and the strength and rigidity of the hybrid member 1D can be enhanced.

[0030] (Fourth Modification of the Embodiment) FIG. 15 is a cross-sectional view showing the hybrid member of the fourth modification. In the hybrid member 1E of the second modification shown in FIG. 15, in addition to the configuration of the hybrid member 1A shown in the above embodiment, a concave portion 3d having the same shape as the steel plate 4 is formed in a portion of the surface 3f of the wood portion 3 facing the flat plate portion 22 where the steel plate 4 is positioned. The steel plate 4 is fixed to the wood portion 3 by structural screws 7 in a state of being housed inside the concave portion 3d of the wood portion 3. A through hole 32 is provided at the position of the concave portion 3d where the high-strength bolt 5 is provided, as in the above embodiment. The steel plate 4 is frictionally joined to the flat plate portion 22 by the high-strength bolt 5. As a result, the surface 3f of the wood portion 3 is in contact with and closely attached to the surface 22f of the flat plate portion 22 facing the wood portion 3 without providing a gap S2 as shown in FIG. 4 or the like. In the material axis direction Da, the side surface 4m of the steel plate 4 is in contact with the side wall surface 3h of the concave portion 3d. In such a configuration, since the side surface 4m of the steel plate 4 is provided to be in contact with the side wall surface 3h of the concave portion 3d in the material axis direction Da, when an axial force acts on the steel member 2, the axial force from the steel plate 4 to the wood portion 3 is transmitted not only by the shear of the structural screws 7 but also directly from the side surface 4m of the steel plate 4 to the side wall surface 3h of the concave portion 3d. Thereby, the performance of axial force transmission from the steel member 2 to the wood portion 3 can be improved. Further, since the inner surface 3f of the wood portion 3 is in contact with and closely attached to the surface 22f of the flat plate portion 22 facing the wood portion 3, local buckling of the flat plate portion 22 can be suppressed. Furthermore, by providing the concave portion 3d in the wood portion 3, when joining the steel plate 4 to the wood portion 3 at a construction site or the like, for example, the operation of aligning the steel plate 4 and the wood portion 3 by scribing becomes unnecessary, and the work efficiency is improved.

[0031] Also, as shown in FIG. 16, the hybrid members 1A to 1E shown in the above embodiment and its modifications may be applied, for example, to the truss portion 101 of the structure 100A. The truss portion 101 includes, for example, a lower chord member 102, an upper chord member 103 disposed above the lower chord member 102, a bundled member 104 and a lattice member 105 disposed between the lower chord member 102 and the upper chord member 103. The hybrid members 1A to 1E can be applied, for example, to the lower chord member 102, the upper chord member 103, the bundled member 104, the lattice member 105, etc. of the truss portion 101. Also, as shown in FIG. 17, it may be applied to the upper chord member 111 that constitutes the cable-stayed beam 110 of the structure 100B. Also, as shown in FIG. 18, the hybrid members 1A to 1E may be applied to the upper chord member 121 that constitutes the arch beam 120 that supports the roof of the structure 100C. Also, as shown in FIG. 19, the hybrid members 1A to 1E may be applied to the upper chord member 131 that constitutes the gable ramen portion 130 that supports the roof of the structure 100D. In addition to this, as long as the gist of the present invention is not deviated from, it is possible to select the configurations listed in the above embodiment or to appropriately change them to other configurations.

Explanation of Reference Numerals

[0032] 1A to 1E Hybrid members 22f Surface 2 Steel material part 32 Through hole 3 Wood part 35 Plugging material 3f Surface 40 Column-beam framework 4 Steel plate 41 Column 5 High-strength bolt 43 Beam 7 Structural screw Da Axial direction of member 22 Flat plate part Dv Vertical direction

Claims

1. A hybrid member formed by joining steel and wood, comprising: a steel member having a flat plate portion extending in the material axis direction; a wooden portion provided adjacent to the flat plate portion; a plurality of steel plates attached to the surface of the wooden portion joined to the flat plate portion by structural screws and joined to the flat plate portion; and the plurality of steel plates are provided at intervals in the material axis direction; A hybrid member, characterized in that each of the plurality of steel plates is fastened to the flat plate portion with high-strength bolts, and the wooden portion and the steel member are joined.

2. In a portion where the steel plate is not attached, a gap is provided between the surface of the flat plate portion and the surface of the wooden portion joined to the flat plate portion, or In a portion of the surface of the wooden portion joined to the flat plate portion where the steel plate is to be attached, a recess having the shape of the steel plate is formed, and the steel plate is attached to the wooden portion by the structural screw in a state of being housed inside the recess. In a portion where the steel plate is not attached, the surface of the flat plate portion and the surface of the wooden portion joined to the flat plate portion are provided in contact with each other. The hybrid member according to claim 1, characterized by the above.

3. In the wooden portion, through holes are formed in a direction perpendicular to the flat plate portion at positions where the high-strength bolts are arranged. The high-strength bolts are provided in the through holes, and the outside of the through holes is blocked by a plugging material. The hybrid member according to claim 1 or 2, characterized by the above.

4. A column-beam structure using a hybrid member, comprising a steel column and a beam installed between the columns, wherein the beam is formed of the hybrid member according to any one of claims 1 to 3.

Images