KR101498720B1 - Design method for steel frame girder having reinforcing member at end lower part thereof - Google Patents

Abstract

The method of designing a steel beam according to the present invention can simplify the design work of a steel beam having a steel frame body, a reinforcing member, and a compression transmission plate. Since the steel beam manufactured by the design method according to the present invention transmits the compressive force transmitted through the steel frame body and the reinforcing member to the supporting point through the compression transfer plate, the sectional strength can be increased, the amount of steel can be reduced, And it is possible to reduce the amount of welding of the joint portion, thereby reducing the construction cost and shortening the air (construction period).

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method of designing a steel frame having a reinforcing member at a lower end thereof,

The present invention relates to a method of designing a steel beam, and more particularly, to a method of designing a steel beam having a steel frame body, a reinforcing member and a compression transmission plate, The present invention relates to a method of designing a steel beam, which can reduce the amount of steel material, reduce the amount of stratification and reduce the welding amount of the welding part, thereby reducing the construction cost and shortening the air (construction period).

Generally, steel beams are made of steel such as H-beams. Figure 1 shows an example in which such steel bars are connected to SRC columns.

The reinforcing members 40 may be provided on both lower ends of the steel frame body 30 to reinforce the sectional strength of the steel frame body 30. As the reinforcing member 40, a T-shaped steel or the like may be used.

The steel frame body 30 is directly connected to the column steel frame 12 by welding with the connecting member 50 and the reinforcing member 40 is directly connected to the column steel frame 12 by welding. On the other hand, reference numeral 14 denotes concrete that covers the column steel frame 12.

The reinforcing member 40 transmits tensile force or compressive force transmitted from the steel frame body 30 to the column steel frame 12 so that the column steel frame 12 is supported by the lower flat plate 12 in order to resist the tensile force or compressive force applied by the reinforcing member 40. [ And a stiffener 16 is provided at a position corresponding to the stiffener 41. The stiffener 16 is provided between the flanges 13 and resists the tensile force or compressive force transmitted from the reinforcing member 40.

In this way, when the reinforcing member 40 is directly connected to the SRC pillar steel frame 12, the field welding amount increases to join the reinforcing member 40 to the pillar steel frame 12. [ It is also necessary to weld the stiffener 16 to the column steel frame 12. In addition, the structure is complicated due to the stiffener 16, so that the quality of the spotted concrete is lowered and the amount of on-site formwork is increased.

On the other hand, even if a steel beam is connected to a CFT column, a steel plate for a diaphragm is required at a joint portion between the reinforcing member and the column steel plate. In addition, the installation of the diaphragm requires a lot of cost, There is a problem that the concrete is difficult to be poured when the frame is installed.

In order to solve the above-mentioned problems, the applicant of the present invention has developed a steel beam capable of transmitting a compressive force transmitted through a steel frame body and a reinforcing member to a column of a compression transfer plate. Korean Patent Application No. 10-2013-0080894 (Hereinafter, referred to as " steel wire frame and its construction method ").

However, since the steel frame has a steel frame body, a reinforcing member, and a shore pressure transmitting plate (compression transfer plate), its structure differs from that of an existing steel frame, complicating structural analysis. Previously, to analyze these steel beams, the single member section was calculated by adding together the vertical load and the live load, without distinguishing the vertical load from the live load.

The Applicant has devised the present invention in order to simplify and effectively perform such structural analysis.

Accordingly, the present invention has an object of solving the problems described in the Background of the Invention and a purpose of simplifying and simplifying the structural analysis of the steel wire rover filed in Korean Patent Application No. 10-2013-0080894.

More particularly, the present invention relates to a structure in which a compressive force transmitted through a steel frame body and a reinforcing member is transmitted to a column (support point) of a compression transfer plate or a compressive force transmitted through a steel frame body is transmitted to a column (support point) And to provide a method of designing a steel frame capable of reducing the amount of steel material and reducing the thickness of the steel frame.

Still another object of the present invention is to provide a method of designing a steel beam that reduces the amount of field welding work by allowing the steel frame body to be directly coupled with the SRC column steel and the reinforcing member (or compression transfer plate) to transmit the compressive force to the concrete covering the column steel frame .

Another object of the present invention is to provide a method of designing a steel frame which can reduce the amount of formwork by improving the quality of the spotted concrete and thereby reducing or eliminating the need for a stiffener by allowing the compressive force to be transmitted to the concrete covering the SRC column steel frame And the like.

It is still another object of the present invention to provide a method of designing a steel beam capable of dispersing a compressive force acting on a joint portion between a reinforcing member and a pillar plate when connecting a steel beam to a CFT column.

Another object of the present invention is to provide a method of designing a steel beam that requires no or less diaphragm for connecting a reinforcing member when connecting a steel beam to a CFT column.

It is still another object of the present invention to provide a design method capable of simplifying and efficiently designing such a steel frame.

In order to solve the above problems, a method of designing a steel beam according to the present invention is a method of designing a steel beam so that a steel beam body and a reinforcing member (or a reinforcing member and a pressure transmitting plate) constituting a steel beam share a vertical load generating a compressive force in a composite section .

That is, the steel beam includes a steel frame body formed to be long along the longitudinal direction of the beam, and a reinforcing member provided on the lower or lower surface of both ends of the steel frame body. The steel frame body has a finishing The load and the weight of the beam and the weight of the slab are to be borne by the reinforcing member, and the reinforcing member is required to bear the live load in the vertical load generating the compressive force in the composite section. The reinforcement member is installed in the leg section of the steel frame and the plastic neutral axis is positioned on the upper side of the reinforcement member so that the reinforcing member acts on the reinforcing member with respect to the vertical load so that the tensile force does not act on the support member, Or other beams).

Another design method according to the present invention may make the load distribution in the vertical direction slightly different from the above. That is, when the live load is large, the load of the live load, the weight of the beam, the weight of the slab and the finish load are burdened in the vertical direction load which generates the compressive force in the composite section of the steel frame body, The rest of the live load is to be borne by the load, and the horizontal load is to be borne by the body of the steel frame. The reinforcement member is installed in the leg section of the steel frame and the plastic neutral axis is positioned on the upper side of the reinforcement member so that the reinforcing member acts on the reinforcing member with respect to the vertical load so that the tensile force does not act on the support member, Or other beams).

Meanwhile, in the above two design methods, the shear force is designed such that the web of the steel frame body is entirely burdened.

In this case, a load acting on the reinforcing member during the vertical load (the remaining part of the live load or live load) acts on the side surface of the end of the reinforcing member, And the plastic neutral axis is located above the reinforcing member and the pressure transmitting plate, so that the compressive force acts on the pressure transmitting plate. Therefore, the compressive force transmitted through the steel frame body and the reinforcing member is transmitted to the supporting point through the pressure transmitting plate.

In the design methods, the compression transfer plate can directly transmit the compressive force to the concrete of the SRC column or the concrete of the RC (PC) column or the steel plate of the steel column or the steel plate of the CFT column or other beams have.

The reinforcing member may be formed of a steel plate of a "ㅗ" shape, a "ㅛ" shape steel, an H shape steel, an A shape steel plate, a ㅗ type steel plate, a ㅛ type steel plate, an H plate, A steel plate, a steel pipe, a bent iron plate with at least one open side, and a CFT, and the reinforcing member and the steel frame body may be formed into a composite cross-section by bolting or welding.

The design method according to the present invention is characterized by the fact that between the concrete of the SRC column, the concrete of the RC (PC) column, the steel column of the steel column, the steel plate of the CFT column, A shim plate may be inserted or an epoxy resin may be filled to compensate for the construction error.

The lower flange of the steel frame body and the upper flat plate of the reinforcing member may be provided with elongated holes formed in the longitudinal direction of the steel beam at positions corresponding to each other. The bolts were fastened to the holes of the lower flange and the upper plate and the compression transfer plate was brought into close contact with the concrete of the SRC column, the concrete of the RC (PC) column, the steel column of the steel column, The lower flange and the upper plate may be welded or bolted together.

Meanwhile, in the designing method according to the present invention, the upper reinforcing bars are disposed on the slab so as to behave as a composite section, or the thickness of the steel plate or the height h of the reinforcing members as the number of the reinforcing members, The firing neutral axis can be positioned above the reinforcing member.

The compression transmission plate may be positioned further toward the support point than the end of the steel frame body. In this case, the steel frame body is joined to the tip of the connecting steel frame 70 extending from the steel column 60 or the front end of the connecting steel frame 90 extending from the steel frame 12 of the SRC column, And is connected to the lower connecting steel frame 80 coupled to the column 60 or coupled to the lower surface of the connecting steel frame 70 or to the covering concrete of the SRC column to transmit the compressive force.

The compression transmission plate may be located at the center of the steel bar body rather than at the end of the steel bar body. In this case, the steel frame body is coupled to the steel frame of the column and the compression transmission plate can be installed to press the concrete covering the steel frame.

Wherein the reinforcing member includes: an upper flat plate coupled to the lower flange of the steel beam along the longitudinal direction; A connecting flat plate welded to the upper flat plate along the longitudinal direction; And a lower flat plate coupled to the lower end of the connecting plate along the longitudinal direction, and a plurality of through holes for fastening the lower flange to the upper flat plate may be formed.

The through-hole may include a slot (slot hole) for temporarily fastening the reinforcing member to the steel frame body.

An iron plate 415 may be installed on the same side of the steel frame body as the compression transmission plate. The steel plate 415 prevents buckling of the beam and serves as a mold when pouring concrete.

The design method according to the present invention may include horizontal ribs 260 that are disposed between the connection plate 121 and the compression transfer plate 120 so as to be perpendicular to the connection plate 121 of the reinforcing member and the compression transmission plate. Lt; / RTI >

In the designing method according to the present invention, the stud embedded in the concrete constituting the column may be provided on the compression transfer plate or the reinforcing bar or the tension member passing through the compression transmission plate may be installed.

The design method according to the present invention may include a vertical rib 570 which is provided on the side of the column of the compression transmission plate so as to be perpendicular to the lower flange of the steel frame body and the compression transmission plate, Plate.

The present invention has the following effects.

First, a steel beam having a steel frame body and a reinforcing member, or a steel beam having a steel frame body, a reinforcing member, and a compression transmission plate can be designed simply and efficiently. That is, when the steel frame body and the reinforcing member share the vertical load generating the compressive force in the composite section, or the steel frame body and the 'reinforcing member and the shore pressure transmitting plate' share the vertical load and the steel frame body is subjected to the horizontal load (wind load and seismic load Etc.) and the shearing force, but the reinforcing member and the pressure transmitting plate are made to exert only the compressive force, so that the steel beam design can be made simple and efficient.

Second, the compressive force transmitted from the steel frame body is transmitted to the support point (for example, a column or another beam) or the compressive force transmitted through the steel frame body and the reinforcement member is transmitted to the support point. Provides a steel bridge design method that can reduce the amount of steel and reduce the floor height.

Third, the steel frame body is directly coupled with the SRC column steel, and the compression transfer plate provides compressive force to the concrete covering the column steel frame, thereby providing a method of designing a steel beam whose welding workload is reduced.

Fourth, it is possible to provide a method of designing a steel beam which can reduce the amount of formwork by improving the quality of the spotted concrete and thereby reducing or eliminating the need for a stiffener by transmitting the compressive force to the concrete covering the SRC column steel frame.

Fifth, a method of designing a steel beam capable of dispersing a compressive force acting on a joint portion between a reinforcing member and a pillar plate when connecting a steel beam to a CFT column is provided.

Sixth, it provides a method of designing a steel beam that requires less or less diaphragm for connecting reinforcing members when connecting steel beams to CFT columns.

Seventh, between the concrete and compression transfer plate of SRC column, between concrete and compression transfer plate of RC (PC) column, between steel frame and compression transfer plate of steel column, between iron plate and compression transfer plate of CFT column, A shim plate may be inserted between the transfer plates or an epoxy resin may be filled to compensate for the construction error.

Eighth, even if the beam length on the design is different from the length of the beam measured in the field due to the vertical error of the column in the subterranean tower down method, it is possible to use the slotted hole formed in the reinforcement member and the lower flange, Or the like.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing an example in which a steel beam according to the related art is connected to an SRC column.
2 is an exploded perspective view showing a steel beam that can be manufactured by a design method according to the present invention;
Fig. 3 (a) is a front view showing the steel frame of Fig. 2; Fig.
3 (b) is a sectional view taken along the line AA 'of FIG. 3 (a).
Fig. 4 (a) is a front view showing a part of another steel beam capable of being manufactured by the designing method according to the present invention. Fig.
4 (b) is a sectional view taken along the line BB 'in Fig. 4 (a).
Fig. 5 is a front view of the steel beam shown in Fig. 4 (a) connected to the SRC column. Fig.
Fig. 6 (a) is a view showing a bending moment generated in a steel beam and a column when a vertical concentrated load is applied in a ramen structure having a steel beam designed according to the present invention. Fig.
FIG. 6 (b) is a view showing a bending moment generated in a steel beam and a column when a horizontal concentrated load is applied in a ramen structure having a steel beam designed according to the present invention. FIG.
Fig. 7 (a) is a front view showing a part of another steel beam which can be manufactured by the designing method according to the present invention. Fig.
7 (b) is a sectional view taken along line CC 'in Fig. 7 (a).
Fig. 8 (a) is a front view showing a part of another steel beam which can be manufactured by the designing method according to the present invention. Fig.
8 (b) is a cross-sectional view taken along line DD 'of FIG. 8 (a).
Fig. 9 is an enlarged view of a portion IX in Fig. 8 (a). Fig.
10 is a front view showing a part of another steel beam which can be manufactured by a design method according to the present invention;
11 is a front view showing another steel beam connected to a CFT column, which may be manufactured by the design method according to the present invention;
Fig. 12 (a) is a front view showing a reinforcing member and a compression transmission plate provided in the steel frame of Fig. 11; Fig.
12 (b) is a plan view showing the reinforcing member and the compression transmission plate of Fig. 12 (a). Fig.
13 is a cross-sectional view showing a reinforcing member provided in the steel frame of FIG. 11 coupled to the steel frame body.
14 is a perspective view showing still another steel frame capable of being manufactured by the designing method according to the present invention;
Figs. 15 and 16 are front views, respectively, showing the steel bars of Fig. 14 connected to the pillar steel frame. Fig.
Figure 17 is a front view of the steel beam shown in Figure 14 connected to the SRC column.
Fig. 18 is a perspective view showing still another steel frame capable of being manufactured by the designing method according to the present invention; Fig.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the inventor should appropriately interpret the concepts of the terms appropriately It should be interpreted in accordance with the meaning and concept consistent with the technical idea of the present invention based on the principle that it can be defined. Therefore, the embodiments described in the present specification and the configurations shown in the drawings are merely examples of the present invention and are not intended to represent all of the technical ideas of the present invention, so that various equivalents And variations are possible.

Hereinafter, the structure of a steel frame that can be manufactured by the design method according to the present invention will be described first, and then a design method will be described.

In addition, the steel beam is installed to be connected to a supporting point (for example, a column or another beam). In the following description, the steel beam is connected to a column for convenience of explanation. The principle of connecting the steel bars to the columns may be applied to the case where the steel bars are connected to other steel bars. In the present specification, the term "support point" is used to refer to a column, another beam, or the like as a part for supporting a steel beam.

In this specification, the term 'composite section'means' steel frame body and reinforcing member ', or' steel frame body, reinforcing member and compression transmission plate '(when steel frame is provided with compression transmission plate) or' steel frame body and reinforcing member Means a member and an upper reinforcing bar (steel reinforced with a slab), or " a steel frame body, a reinforcing member and a compression transmission plate and an upper reinforcing bar ", when the steel frame is provided with a compression transmission plate, It will be obvious to those of ordinary skill in the art.

FIG. 2 is an exploded perspective view showing a steel beam that can be manufactured by the design method according to the present invention, FIG. 3 (a) is a front view showing the steel beam, and FIG. 3 (b) .

Referring to the drawings, a steel frame 100 includes a steel frame body 110, a reinforcing member 120, and a compression transmission plate 150 installed at an end of the reinforcing member 120.

The steel frame body 110 is a long member formed along the longitudinal direction of the beam 100. Preferably, the steel frame body 110 is an H-shaped steel having an upper flange 111, a lower flange 112 and a web 113.

At both ends of the steel frame body 110, bolt holes 116 for connection with the column steel frame are formed.

The reinforcing members 120 are joined to the lower surfaces of both ends of the steel frame body 110. The joining of the reinforcing member 120 and the steel frame body 110 may be performed by welding or the like.

The reinforcing member 120 may include a connecting plate 121 and a lower plate 122.

The connecting plate 121 is installed vertically to the lower flange 112 along the longitudinal direction of the beam and the lower plate 122 is installed horizontally along the longitudinal direction at the lower end of the connecting plate 121. The width of the lower flat plate 122 may be greater than, equal to, or narrower than the width of the lower flange 112.

Although the figure shows a reinforcing member 120 (i.e., a "ㅗ" shaped steel) having a "ㅗ" shaped cross section in which one connecting flat plate 121 is provided on the lower flat plate 122, A reinforcing member of a "ㅛ" -shaped cross section in which a flat plate 121 is provided (that is, a "ㅛ" shaped steel) may be used.

Further, it is preferable that at least one of the H-shaped steel, the A-shaped steel, the ㅗ-shaped steel plate, the ㅛ-shaped steel plate, the H-shaped steel plate, Bended iron plates with open sides, concrete filled steel tubes (CFT) can also be used as reinforcing members. The iron plate of the "ㅗ" -shaped section and the iron plate of the "ㅛ" -shaped section and the iron plate of the "H" -shaped section and the iron plate of the ┌shaped section have the iron plate as the "ㅗ" Shaped cross section and 'a' shaped cross section, and the rectangular steel pipe is a pipe having a closed rectangular interior space, and the circular steel pipe is a pipe having a closed circular space. The bending iron plate having at least one open side is, for example, a structure having a quadrangular internal space, one face being opened, three faces being closed, and the open face being folded so that the iron plate is brought into contact with the lower flange 112 do.

In the present invention, the reinforcing members (including reinforcing members 220, 320, 620, 720, and 820 described later) and the steel frame body 110 are integrally formed by bolting or welding to form a composite section.

The compression transmission plate 150 is coupled to the ends of the pillars on both sides of the reinforcing member 120 (i.e., the ends of the pillars) . Specifically, the compression transfer plate 150 is coupled to the end side surface 125 of the reinforcing member 120.

Preferably, the compression transfer plate 150 is positioned at the center of the steel beam 100, rather than at the end of the steel beam body 110. Therefore, when the SRC column is connected to the steel frame 100, the steel frame body 110 is joined to the column steel frame, and the compression transfer plate 150 is placed on the surface of the covered concrete. This point will be described in detail below.

A stud bolt 152 may be provided on the surface of the compression transmission plate 150 facing the column. The stud bolt 152 allows the cover concrete of the SRC column and the compression transfer plate 150 to be integrated.

As an alternative to the stud bolt 152 or with the stud bolt 152, a reinforcing bar (not shown) or a tension member (not shown) may be provided through the compression transmission plate 150. The reinforcing bars and the tension members may be mechanically fixed or welded to the lower flat plate 122 after passing through the compression transmission plate 150.

As described above, since the reinforcement member 40 is connected to the column steel frame 12 by welding when the conventional steel frame 20 is connected to the SRC column, the amount of field welding work is large. In contrast, since the compression transfer plate 150 according to the present invention is installed on the surface of the covered concrete, it is possible to drastically reduce the amount of on-site welding work.

In addition, since the conventional reinforcing member 40 directly transmits the compressive force to the column steel frame 12, the stiffener 16 is required. As a result, the work of placing concrete on the spot becomes complicated and the amount of formwork is increased. However, The above-mentioned problem can be solved because the compressive force 150 transmits compressive force to the covered concrete.

Although the steel frame 100 is provided with the compression transmission plate 150 in the above description, the steel frame 100 may have a structure in which the reinforcing member 120 directly contacts the column without the compression transmission plate 150 In this case, the compressive force transmitted through the steel frame body 110 is directly transmitted to the column (support point) through the reinforcing member 120. [

Fig. 4 (a) is a front view showing a part of another steel beam which can be manufactured by the designing method according to the present invention, and Fig. 4 (b) is a sectional view taken along the line B-B 'in Fig. 4, the same reference numerals as those in Figs. 1 to 3 denote the same elements.

The steel frame 200 is different from the steel frame 100 in that the reinforcing member 220 has a horizontal rib 260.

The horizontal rib 260 is a flat plate coupled to the compression transmission plate 150 and the connection plate 121 so as to be perpendicular to the compression transmission plate 150 and the connection plate 121.

5 is a front view showing the steel beam 200 connected to the SRC column. The steel frame body 110 is joined to the column steel frame 12 by a connecting member 50 and welding and the compression transmission plate 150 is installed on the surface of the covered concrete 14. Therefore, the compression force applied by the compression transmission plate 150 does not directly act on the column steel frame 12 but acts on the covered concrete 14, so that the stiffener 16 is unnecessary or less necessary.

In addition, since the compression transfer plate 150 applies a compressive force to the side surface of the covered concrete 14, the compressive force of the column is increased due to the three-axis constraining effect of the covered concrete.

On the other hand, when the steel beam 200 does not have the compression transmission plate 150, the reinforcing member 220 directly transmits the compressive force to the covered concrete 14.

The present invention makes it possible to design the steel frame having such a structure simply and efficiently.

Vertical load and horizontal load are applied to the beam installed on the structure. Vertical load includes fixed load and live load, and horizontal load includes seismic load and wind load. The fixed load includes the weight of the beam, the weight of the slab, and the finishing load (finishing mortar, no-load concrete, access floor, ceiling, etc.). The ratio of the normal fixed load to the live load (fixed load / live load) is in the range of 2/8 to 7/3.

The design method according to the present invention allows the steel frame body 110 to bear the finishing load, the weight of the beam, and the weight of the slab in the vertical direction load generating the compressive force in the composite section, (In the absence of the compression transmission plate 150, the reinforcing member 120 is liable to live load). In addition, the horizontal load imposes the entire load on the steel beam body 110, and the shear force causes the web 113 of the steel beam body 110 to be entirely burdened.

At this time, the reinforcing member 120 and the compression transfer plate 150 are designed so that only compressive force acts and no tensile force acts. For this, the reinforcing member 120 and the compression transfer plate 150 are installed in a section where a negative bending moment is generated by a vertical load, and the firing neutral axis is installed in the steel frame body 110, So as to be located above the compression transfer plate 150. 6 (a) and 6 (b) illustrate bending moments acting on the steel beam and the column. FIG. 6 (a) 6 (b) shows the bending moment generated in the steel beam 200 and the column when the load (arrow) acts. FIG. 6 (b) shows the bending moment generated in the steel beam 200 ) And the bending moment generated in the column.

The reinforcing member 120 and the compression transfer plate 150 are installed in the section N where the negative moment acts in the steel frame when the firing neutral axis is located above the reinforcing member 120 and the compression transmission plate 150 The compressive force transmitting plate 150 moves the reinforcing member 120 and the compressive force transmitting plate 150 with respect to the vertical force so that only the compressive force acts on the reinforcing member 120 and the compressive force transmitting plate 150, To the column.

This principle is also applicable to the case where the compression transmission plate 150 is not provided. That is, when the firing neutral axis is located above the reinforcing member 120, if the reinforcing member 120 is installed in the section N where negative moments act in the steel beam, the reinforcing member 120 So that the reinforcing member 120 transmits the compressive force transmitted through the steel frame body 110 to the column.

(Not shown) in the slab (not shown in the figure) to form a composite cross section, or to adjust the diameter or number of the upper reinforcing bars or the thickness of the steel plate constituting the reinforcing member 120, The reinforcing member 120 and the compression transfer plate 150 can be positioned in the steel frame body 110 by adjusting the sectional height of the reinforcing member 120 and the compression transmission plate 150. [

In addition, a clearance between the cover concrete of the SRC column and the compression transmission plate 150, a clearance between the concrete of the RC (PC) column and the compression transmission plate 150, a gap between the steel column of the steel column and the compression transmission plate 150 A clearance between the steel plate of the CFT column and the compression transfer plate 150, and a gap between the other beam and the compression transmission plate 150 when the compression plate is connected to another beam, so that the compressive force is transmitted to the column. A shim plate (not shown in the drawing) may be inserted or an epoxy resin (not shown in the drawing) may be filled. The gaps may occur due to a construction error or the like. In the present invention, the gaps may be inserted into the gaps or the epoxy resin may be filled to transfer the compressive force.

As described above, in the present invention, when the tensile force is generated in the reinforcing member 120 and the compression transfer plate 150 due to the horizontal load, the horizontal load is entirely borne by the steel frame body 110, .

As a modification of the design method of the present invention, the load distribution in the vertical direction can be made slightly different from the above. For example, when the live load is large, the steel frame body 110 may bear a part of the live load, the dead load, the weight of the beam, and the weight of the slab in the vertical direction load generating the compressive force in the composite section, The compression transfer plate 150 can bear the remaining part of the live load among the vertical loads generating the compressive force in the composite section. In addition, the horizontal load imposes the entire load on the steel beam body 110, and the shear force causes the web 113 of the steel beam body 110 to be entirely burdened. Such modifications will be readily apparent to those skilled in the art having referred to the above described method of design.

Fig. 7 (a) is a front view showing a part of another steel beam capable of being manufactured by the designing method according to the present invention, and Fig. 7 (b) is a cross-sectional view taken along the line C-C 'in Fig. 7 (a) and 7 (b), the same reference numerals as those in Figs. 1 to 5 denote the same components.

The steel frame 300 is different from the steel frame 100 of the first embodiment in that a steel pipe, more specifically a rectangular steel pipe, is used as the reinforcing member 320. Concrete may be selectively filled in the steel pipe.

8 (a) is a front view showing a part of another steel beam capable of being manufactured by the designing method according to the present invention, FIG. 8 (b) is a sectional view taken along the line DD ' Fig. 5 is an enlarged view of a portion IX of Fig. 8A and 8B and the reference numerals in FIG. 9 denote the same elements as those in FIG. 1 to FIG. 7B.

The steel bar 400 is different from the steel bar 200 in that an iron plate 415 is installed at both ends of the steel bar body 110.

The steel plate 415 is installed to be coupled to the upper and lower flanges 111, 112 and the web 113. Steel plate 415 prevents buckling of the beam. Also, the steel plate 415 serves as a mold for casting the covered concrete 14, thereby reducing the work amount of the formwork.

10 is a front view showing a part of another steel frame which can be manufactured by the designing method according to the present invention. 10, the same reference numerals as those in Figs. 1 to 9 denote the same elements.

The steel wire 500 is differentiated from the steel wire 200 in that a vertical rib 570 is provided on the compression transmission plate 150. The vertical ribs 570 are coupled to the lower flange 112 and the compression transfer plate 150 to be perpendicular to the lower flange 112 and the compression transfer plate 150. One or more vertical ribs 570 may be installed so that the vertical ribs 150 are embedded in the covering concrete 14 to integrate the covering concrete 14 and the compression transfer plate 150.

Fig. 11 is a front view showing another steel beam which can be manufactured by the present invention connected to a CFT column, Fig. 12 (a) is a front view showing a reinforcing member provided in the steel beam and a compression transmission plate, ) Is a plan view showing the reinforcing member and the compression transfer plate. 11 to 12 (b), the same reference numerals as in Figs. 1 to 10 denote the same elements. On the other hand, as is known, the CFT column is a column surrounded by an iron plate 19 and filled with concrete.

The steel frame 600 includes a steel frame body 110 directly coupled to the steel plate 19, a reinforcing member 620 coupled to the lower surfaces of both ends of the steel frame body 110, and an end side surface 625 of the reinforcing member 620 (Not shown).

The steel frame body 110 may be made of H-shaped steel or the like and is joined to the steel plate 19 by a connecting member 50 and welding. The steel frame body 110 includes upper and lower flanges 111 and 112 and a web 113. The lower flange 112 has a first fastening hole 615 corresponding to a slot hole 631, And the second fastening hole 617 corresponding to the bolt hole 633 are formed. The first fastening hole 615 is a long hole formed along the longitudinal direction of the beam.

The reinforcing member 620 includes an upper plate 621 coupled to the lower flange 112 along the longitudinal direction of the beam, a connecting plate 622 vertically welded to the upper plate 621 along the longitudinal direction, And a lower flat plate 623 horizontally coupled to the lower end of the connecting flat plate 622 along the direction.

A plurality of through-holes for fastening the lower flange 112 are formed on the upper flat plate 621. The through hole includes a slot hole (long hole 631) and a bolt hole 633. [

The slot hole (long hole 631) is a hole for temporarily fastening the reinforcing member 620 to the steel frame body 110. The bolt is fastened to the slot hole 631 and the first fastening hole 615 to form the reinforcing member 620 (Temporarily) to the steel frame body 110 (see FIG. The temporary fastening may be accomplished by manual operation of the operator or a fastening device or the like. It is preferable that the slot hole 631 is located on both sides of the bolt hole 633 in order to effectively perform the temporary fastening.

The slot hole 631 and the first fastening hole 615 are elongated holes formed in the longitudinal direction of the beam. The bolts are fastened to the slot hole 631 and the first fastening hole 615, The plate 150 is brought into close contact with the steel plate 19 and then the compression transfer plate 150 and the steel plate 19 are welded and the upper plate 621 and the lower flange 112 are welded together. That is, even if there is a gap between the compression transmission plate 150 and the steel plate 19 due to a construction error or the like, since the slot hole 631 and the first fastening hole 615 are elongated, the reinforcement member 620 The compression transmission plate 150 can be brought into close contact with the steel plate 19 by sliding.

This configuration is very useful when the length of the beam on the design is different from the length of the beam measured on the site due to the vertical error of the column in the underground tower down method.

The bolt hole 633 is a hole through which the bolt 633 and the second fastening hole 617 are formed so that a bolt (not shown) is provided to fasten the reinforcing member 620 to the steel bar body 110, So that the reinforcing member 620 is coupled to the steel frame body 110. As shown in FIG.

As an alternative to the coupling using the bolt, after the reinforcing member 620 is temporarily fastened to the steel frame body 110 using the slot hole 631 as described above, the upper plate 621 may be coupled to the lower flange 112. 13, it is preferable that the width of the upper flat plate 621 is wider than the width of the lower flange 112. [

The compression transmission plate 150 is attached to the end side surface 625 of the reinforcing member 620. The compression transmission plate 150 is joined to the steel plate 19 by welding and transmits a compressive force to the steel plate 19. The compression transfer plate 150 can simultaneously serve as a back strip or an end tab when welding the lower flange 112.

As described above, since the compression transmission plate 150 disperses the compressive force and transmits the compression force to the steel plate 19, the diaphragm provided for connection of the reinforcing member in the existing CFT column is not required or required. It is difficult and costly to install the diaphragm on the CFT column, and it is considered that the effect of the present invention is great considering that the diaphragm makes it difficult to pour concrete.

In the meantime, although it has been described that the steel beam 600 is connected to the CFT column, the steel beam can be used for the SRC column by allowing the end of the steel beam body to extend further outward than the reinforcing member. In this case, the compression transfer plate is installed on the surface of the covered concrete, and the steel frame body is connected to the column steel frame.

By the same principle, by adjusting the installation position of the reinforcing member or the length of the reinforcing member so that the compression transmission plate of the steel bars 100, 200, 300, 400, 500 is located on the same plane as the end face side of the steel frame body, (100) 200, 300, 400 and 500 to the CFT column. In this case, the compression transmission plate and the steel frame body are joined to the pillar plate 19.

In addition, when the steel bars 100, 200, 300, 400, 500, and 600 do not have compression transmission plates, the reinforcing members are disposed to directly contact the pillars (supporting points) Will be readily apparent to those skilled in the art having referred to the above description of the specification.

The process of connecting the steel beam 600 to the CFT column will now be described.

First, the bolt is fastened to the slot hole 631 and the first through hole 615 to fasten the reinforcing member 620 and the steel stem body 110 together.

Then, the steel beam 600 is lifted and the steel frame body 110 is coupled to the steel plate 19. The coupling may be accomplished using a connecting member 50 and a bolt.

After the steel frame body 110 is coupled to the steel plate 19, bolts are inserted into the bolt holes 633 and the second fastening holes 617 to fasten the steel frame body 110 to the reinforcement member 620. At this time, when the coupling is performed, the compression transmission plate 150 is closely attached to the steel plate 19, and then the compression transmission plate 150 and the steel frame body 110 are welded to the steel plate 19 by welding.

In the case where the compression transmission plate 150 is not brought into close contact with the steel plate 19 due to errors in constructional errors and product dimensions, that is, when there is a gap between the compression transmission plate and the steel plate 19, The gap may be grouted with epoxy or the like to transmit the compressive force.

On the other hand, a tensile steel or a tensile material may be installed on the upper side of the steel beams 100, 200, 300, 400, 500, 600, and the tensile steel or the tensile material is embedded in the slab concrete. The tensile bars or tensions resist the warping of steel beams.

FIG. 14 is a perspective view showing another steel beam which can be manufactured by the designing method according to the present invention, and FIG. 15 is a front view showing the steel beam connected to a column steel frame.

The steel frame 700 includes a steel frame body 110, a reinforcing member 720 coupled to the lower surfaces of both ends of the steel frame body 110 and a compression transmission plate 150 coupled to an end of the reinforcing member 720, Respectively.

The reinforcing member 720 is extended from the steel bar body 110 to the column more than the steel bar body 110 and the bolt hole 155 is formed in the compression transmission plate 150, And a bolt hole 117 is formed in the upper flange 111 of the flange 111.

The steel frame 700 includes upper and lower flanges 111 and 112 and a web 113. A first fastening hole 615 and a second fastening hole 617 are formed in the lower flange 112. The first fastening hole 615 is a slot formed to correspond to a slot hole of the reinforcing member 720 and the second fastening hole 617 is a bolt fastening hole formed to correspond to a bolt hole of the reinforcing member 720.

The reinforcing member 720 includes an upper plate 621, a connecting plate 622, and a lower plate 623. A bolt hole and a slot hole (long hole) are formed in the upper flat plate 621. The structure and role of the slot hole (long hole) and the first fastening hole 615 are the same as those of the slot hole (long hole) and the first fastening hole 615.

15, when the connecting steel frame 70 is installed on the steel column 60, the end of the steel frame body 110 is engaged with the front end 75 of the connecting steel frame 70 and the compression transmitting plate 150 Is coupled to the steel column 60.

The connection between the steel frame body 110 and the connecting steel frame 70 can be achieved by connecting plates 710 and 712 and bolts.

The coupling of the compression transmission plate 150 and the steel column 60 may be by bolting and / or welding. Since the bolting operation is a horizontal bolting method, it is advantageous that the worker can sit on the beam and work.

16 shows a case where the lower connecting steel frame 80 is installed on the lower surface of the connecting steel frame 70. The end connecting plate 81 of the lower connecting steel frame 80 and the compression transmitting plate 150 are connected to the bolts 156, respectively. Therefore, the compressive force acting on the compression transmission plate 150 is transmitted to the end plate 81. [

17 shows that the steel beam 700 is connected to the SRC column. The connecting steel frame 90 is extended from the pillar steel frame 12 and the steel frame body 110 is coupled to the connecting steel frame 90 by the connecting plates 710 and 712. The bolt hole 156 of the compression transmission plate 150 is provided with a stud bolt.

Although the steel beam 700 has the compression transmission plate 150 in the above description, the steel beam 700 may not include the compression transmission plate. In this case, the reinforcing member directly compresses the column (support point) .

18 is a perspective view showing still another steel frame that can be manufactured by the designing method according to the present invention.

The steel frame 800 includes a steel frame body 110, a reinforcing member 820 coupled to lower ends of both ends of the steel frame body 110 and a connecting plate 810 coupled to the steel frame body 110.

The steel frame 800 is different from the steel frame described above in that it does not have the compression transmission plate 150, but the compression transmission plate 150 may be provided.

The connecting plate 810 is a flat plate coupled to the web of the steel frame body 110 and / or the upper and lower flanges, and has bolt holes for connecting the steel frame 800 to another beam.

It should be understood by those skilled in the art that the design method of the steel frame 200 is described above. However, those skilled in the art will appreciate that the steel frame 100, 300, 400, 500, 600, 700, It can be easily applied. Therefore, the description of the method of designing the steel bars 100, 300, 400, 500, 600, 700, 800 will be omitted.

Although it has been described above that the reinforcing member and the compression transmission plate are coupled to the lower surface of the lower flange 112, the reinforcing member and the compression transmission plate may be coupled to the lower surface of the steel frame body, have. The lower end of the connecting plate 121 is welded to the upper surface of the lower flange 112 and the lower plate 122 is welded to the connecting plate 121 And to the web 113. In the embodiment shown in FIG. The lower flat plate 623 may be coupled to the upper surface of the lower flange 112 and the upper flat plate 621 may be coupled to the coupling plate 622 and the web 113. In this case also, if the reinforcing member and the compression transfer plate are installed in the negative moment section and the plastic neutral axis is located above the reinforcing member and the compression transmission plate, only the compressive force acts on the reinforcing member and the compression transmission plate, . In the meantime, since such a configuration will be readily apparent to those skilled in the art with reference to the present specification, further detailed description will be omitted.

12: Column steel frame 14: Covered concrete
30, 110: steel frame body 50: connecting member
40, 120, 220, 320, 620, 720, 820:
60: steel column 70, 90: connecting steel frame
150: compression transfer plate 260: horizontal rib
415: Iron plate 570: Vertical rib
20, 100, 200, 300, 400, 500, 600, 700, 800:

Claims (16)

The steel frame body is elongated along the longitudinal direction of the beam and the reinforcing member is installed on the lower or lower surface of both ends of the steel frame body,
In the steel frame body, the weight of the beam, the weight of the slab and the finishing load are burdened in the vertical load generating the compressive force in the composite section, and the reinforcing member imposes the live load in the vertical load generating the compressive force in the composite section, The steel frame body should bear it,
The reinforcement member is installed within the leg section of the steel frame and the plastic neutral axis is positioned above the reinforcement member so that the reinforcing member is compressed by the vertical load and the tensile force is not applied by the vertical load,
The thickness of the steel plate constituting the reinforcing member or the cross-sectional height (h) of the reinforcing member is adjusted so that the firing neutral axis is positioned above the reinforcing member Wherein the method comprises the steps of: The reinforcing member is installed on the lower or lower surface of both ends of the steel frame body and the compression transmission plate is coupled to the end side of the reinforcing member at the support point side,
The reinforcing member and the compression transfer plate bear the live load in the vertical direction load which generates the compression force in the composite section, The horizontal load is made to bear the steel frame body,
The reinforcement member and the compression transmission plate are installed in the leg section of the steel frame and the plastic neutral axis is positioned above the reinforcing member so that the compressive force acts on the reinforcing member and the compression transmission plate by the vertical load and the tensile force does not act, And a compressive force is transmitted to the supporting point. The steel frame body is elongated along the longitudinal direction of the beam and the reinforcing member is installed on the lower or lower surface of both ends of the steel frame body,
The steel frame body is subjected to a part of the live load, the weight of the beam, the weight of the slab and the finishing load in the vertical direction load generating the compressive force in the composite section, and the reinforcement member absorbs the remaining part of the live load The horizontal load is to be borne by the steel frame body,
The reinforcement member is installed within the leg section of the steel frame and the plastic neutral axis is positioned above the reinforcement member so that the reinforcing member is compressed by the vertical load and the tensile force is not applied by the vertical load, A method of designing a steel beam. The reinforcing member is installed on the lower or lower surface of both ends of the steel frame body and the compression transmission plate is coupled to the end side of the reinforcing member at the support point side,
In the steel frame body, the load of the live load, the weight of the beam, the weight of the slab and the dead load are burdened in the vertical load generating the compressive force in the composite section, and the reinforcing member and the compression transfer plate are subjected to live load The horizontal load is to be borne by the steel frame body,
The reinforcing member and the compression transmission plate are installed in the leg section of the steel frame and the plastic neutral axis is positioned on the upper side of the reinforcing member so that the reinforcing member and the compression transmitting plate are subjected to the compressive force and the tensile force does not act, Wherein the method comprises the steps of: The method according to claim 2 or 4,
The compressive transmission plate transmits the compressive force to the steel plate of the steel frame or the CFT column of the concrete or steel column of the covered concrete of the SRC column or the RC column,
The reinforcing members are at least one member selected from the group consisting of 'ㅗ' steel, ㅛ steel, H steel, 'steel, ㅗ steel plate, ㅛ steel plate, H steel plate, Wherein the reinforcement member and the steel frame body are formed of a composite section integrally formed by bolting or welding. The method according to claim 2 or 4,
A shim plate is inserted between the concrete covering of the SRC column, the concrete of the RC column, the steel frame of the steel column, the steel plate of the CFT column and the other transmission beam and the compression transmission plate, or epoxy resin is filled to compensate the construction error Wherein the method comprises the steps of: The method according to claim 2 or 4,
The lower flange of the steel frame body and the upper flat plate of the reinforcing member are respectively provided with slots formed long in the longitudinal direction of the steel beam,
The bolts are fastened to the holes of the lower flange and the upper plate and the compression transfer plate is made to adhere to the cover concrete of the SRC column, the concrete of the RC column, the steel frame of the steel column, the steel plate of the CFT column, And the upper flat plate are welded or bolted to each other. 5. The method according to any one of claims 2 to 4,
The thickness of the steel plate constituting the reinforcing member or the cross-sectional height (h) of the reinforcing member is adjusted so that the firing neutral axis is positioned above the reinforcing member Wherein the method comprises the steps of: The method according to claim 2 or 4,
The compression transmission plate is positioned on the column side of the end portion of the steel frame body,
The steel frame body is joined to the tip of the connecting steel frame 70 extending from the steel column 60 or to the end of the connecting steel frame 90 extending from the steel frame 12 of the SRC column,
Characterized in that the compression transmission plate is coupled to the steel column (60) or connected to the lower connecting steel frame (80) connected to the lower surface of the connecting steel frame (70) or in contact with the covering concrete of the SRC column Design method. The method according to claim 2 or 4,
Wherein the compression transmission plate is disposed at the center of the steel beam body and the compression beam transmitting plate is installed to press the concrete covering the steel beam body. 5. The method according to any one of claims 1 to 4,
The reinforcing member
An upper flat plate coupled to the lower flange of the steel beam along the longitudinal direction;
A connecting flat plate welded to the upper flat plate along the longitudinal direction; And
And a lower plate coupled to a lower end of the connecting plate along the longitudinal direction,
And a plurality of through holes for fastening with the lower flange are formed on the upper flat plate. 12. The method of claim 11,
Wherein the through hole includes a slot hole for temporarily fastening the reinforcing member to the steel frame body. The method according to claim 2 or 4,
Wherein a steel plate (415) is provided on the same plane as the compression transmission plate, and the steel plate (415) serves as a buckling prevention and die form in the steel frame body. The method according to claim 2 or 4,
And a horizontal rib (260) coupled to the connection plate (121) and the compression transfer plate so as to be perpendicular to the connection plate (121) of the reinforcement member and the compression transmission plate. The method according to claim 2 or 4,
Wherein the compression transfer plate is provided with a stud embedded in the concrete forming the column or a reinforcing bar or a tension member passing through the compression transmission plate. The method according to claim 2 or 4,
And a vertical rib (570) coupled to the lower flange and the compression transmission plate so as to be perpendicular to the lower flange of the steel frame body and the compression transmission plate is installed on the column side surface of the compression transmission plate.

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