KR100690197B1 - Steel beam with plate type shear connector and Steel composite beam using the steel beam - Google Patents

Abstract

The present invention is a steel member used to form a steel concrete composite beam, a channel type consisting of a bottom plate, both side wall plate formed integrally upward from both sides of the bottom plate, and a connecting plate formed integrally from each of the side wall plate The flat beam sheath connector which is joined to each connecting plate in parallel with the longitudinal direction of the steel beam, the channel-shaped steel beam, and has a plurality of holes in the steel plate having a predetermined length and width, and the gap and warping of the channel steel beam A plurality of connecting members joined perpendicularly to the longitudinal direction of the channel-shaped steel beams to restrain; An interlocking engagement of the diaphragm perpendicularly to the longitudinal direction of the steel sheet for increasing the attachment and pressure restraint effect at predetermined intervals therebetween And a rim key.

Composite beam, U-shaped steel sheet, sheer connector, engagement key, connecting member

Description

Steel beam with plate type shear connector and Steel composite beam using the steel beam}

The objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and the preferred embodiments associated with the accompanying drawings.

1 is a perspective view showing a steel permanent formwork beam according to an embodiment of the present invention.

Figure 2a, Figure 2b is a perspective view showing a flat-type sheer connector applied to the steel permanent formwork beam according to the present invention.

3a to 3c is a perspective view showing an engagement key applied to the steel permanent formwork beam according to the present invention.

Figure 4 is a perspective view showing a steel permanent formwork beam according to another embodiment of the present invention.

5a to 5d is a perspective view showing a connection member applied to the steel permanent formwork beam according to another embodiment of the present invention.

Figure 6 is a cross-sectional perspective view showing an example of forming a steel concrete composite beam using a permanent steel formwork beam according to an embodiment of the present invention.

7 is a cross-sectional view showing an example of integrally placing the beam and the slab using the steel permanent formwork beam and the deck plate according to an embodiment of the present invention.

8A and 8B are perspective and cross-sectional views of a conventional TSC beam.

<Explanation of Signs of Major Parts of Drawings>

10: channel steel beam 11: bottom plate

12, 12 ': side wall 13, 13': connecting plate

20: flat type sheath connector 22, 24: hole

25: connecting rebar 30: engagement key

31: steel plate 32: hole

34: plate 36: rebar

44: connecting plate 46: welded wire mesh

48: metal lath 50: slab concrete

52, 54: slab reinforcement 60: beam concrete

70: deck plate

The present invention relates to a steel permanent formwork beam having a plate-shaped sheer connector for realizing a steel concrete composite beam (steel composite member) synthesized from the steel beam and the field-stretched concrete, and a steel concrete composite beam using the same as a structural element.

Steel concrete composite beam is made of steel beam and reinforced concrete to behave as a single member, so that most of the compressive stress is applied to concrete when tensile moment is applied, and tensile stress is to be applied to steel. It is possible to secure the floor space of building structures or the geometry of bridge structures, to make long span structures by increasing the resistance strength and resistance stiffness of beam section, and to increase the ultimate performance and deformation performance.

H-shaped steel, which is generally used to implement steel concrete composite beams, is a member cross section that effectively resists tensile and compressive forces caused by bending in terms of steel usage. Since the neutral axis of the composite section moves to the upper flange side, the concrete slab bears most of the compressive force, so the upper flange is used as an inefficient bending moment resisting section element. In addition, since the performance of the composite beam member is excellent in terms of strength evaluation, it is widely applied to long spans. In this case, the resistance stiffness of the cross section decreases, indicating problems of usability such as excessive deflection and vibration.

In order to solve this problem, a steel-reinforced concrete beam (SRC beam) has been developed to surround the exterior of H-beams of composite beams with reinforced concrete. SRC beam has the advantages of excellent strength and stiffness of the cross section, but its own weight is very increased, so it requires a close attention to formwork and copper construction during site construction. In addition, there is no contribution of concrete surrounding H-shaped steel to tensile stress occurring in the lower section of the beam member in the constant moment section. Therefore, it can be called an inefficient structural section, and the concrete bending crack is visible to the naked eye. have.

TSC beams are known to solve the problems of inefficiency and usability of upper flanges in composite beams using H-beams as described above, and problems of workability and cross section inefficiency in steel reinforced concrete beams. .

As shown in FIGS. 8A and 8B, the TSC beam is composed of the lower steel plate 11, the web steel sheets 12 and 12 ', and the upper steel plates 13 and 13', and each steel plate is integrated to have a resistance to working external force. . At this time, the upper steel plate (13, 13 ') is provided with a stud (25) for resisting the horizontal shear force at the interface with the concrete slab 50 and the composite beam behavior. In addition, when tensile cracks are generated in the lower concrete 61 inside the steel formwork 10 due to the bending moment, the composite sheet cross-sectional strength may not be reached and may be destroyed, so the lower steel sheet 11 may be controlled to control the tensile cracking. Install studs 15 on the In addition, the top of the TSC beam to prevent the spread of the web steel plate (12, 12 ') when placing concrete, and attaching the through-bolt or section steel (20) for fixing the width for ease of upper slab operation. Reference numeral '55' represents slab formwork, and '52' and '54' represent slab reinforcing bars.

However, in the case of the TSC beam having the above-described configuration, since the stud 25 used as the shear connecting member is a flexible connecting member, the perfect composite effect between the dissimilar materials, that is, the interface between the steel and the concrete slab is reduced, and the rigidity of the stud 25 is reduced. Lack of relative slip between steel and concrete occurs at the interface, resulting in the failure to reach the material strength and sufficient deformation performance of the lower steel sheet 11.

In addition, the compressive force is generated in the upper concrete 62 due to the vertical concentrated load or bending moment acting on the composite member. This compressive force causes the upper concrete 62 to expand (orthogonal to the member) to form the web steel sheets 12 and 12 '. It is not effective for the stability of the member due to the phenomenon of opening. In the state before the concrete 60 is placed inside the TSC beam, the open cross section causes deformation of the web steel sheets 12 and 12 'by lifting work by a crane and load during construction by an operator or construction material. It is easy to cause geometric instability of the cross section.

In addition, the stud 15, which is a shear connection member, is disposed to resist the occurrence of slip between the filled concrete and the lower steel plate 11 inside the TSC beam, but the rigidity of the stud 15 and the projected area of the concrete acupressure resistance are small. The effect of restraint resistance on tensile cracking of (61) cannot be expected. That is, after a certain load, the lower steel sheet 11 below the neutral shaft reaches yield strength and causes tensile deformation. The inner lower concrete 61 cannot maintain the same level of strain as the lower tensile strain of the steel, so that the attachment surface breakage and tension Relative slip occurs due to cracking or the like. In order to suppress such relative slip deformation, the interloacking action should be sufficiently induced between the inner lower concrete 61 and the lower steel plate 11, and the stud is the lower concrete 61 filled inside the TSC beam as a soft connecting member. There is a problem that the restraint acupressure effect cannot be exerted sufficiently so that the lower steel sheet 11 cannot reach and maintain a sufficient firing zone.

The present invention has been made in view of the above-described problems of the TSC beam, the cross-sectional phenomenon is prevented from the vertical load such as construction load, steel permanent formwork beam and steel using the improved composite effect between the steel and concrete slab It is an object to provide a concrete composite beam.

In addition, the present invention solves the problem that the steel sheet material of the sub-neutral shaft portion of the composite section does not reach the complete plasticization due to the slip between the concrete filled inside the beam and the bottom plate of the beam, and the concrete filled inside the beam It is an object of the present invention to provide steel permanent formwork beams and steel concrete composite beams using the same.

In addition, the present invention is installed steel permanent formwork beam to install the interloacking key (interloacking key) so that a sufficient acupressure effect and shear effect between the bottom plate and the inner concrete of the beam to reach the sufficient plastic deformation It is an object to provide a steel concrete composite beam using the same.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a perspective view showing a steel permanent formwork beam according to an embodiment of the present invention, Figures 2a to 2c is a perspective view showing a flat-type sheer connector applied to the steel permanent formwork beam according to the present invention, Figure 3a to Figure 3c is a perspective view showing an engagement key applied to the steel permanent formwork beam according to the present invention.

As shown in FIG. 1, the steel permanent formwork beam 1 according to an embodiment of the present invention includes a bottom plate 11, two side wall plates 12 and 12 ′, and a connecting plate 13 and 13 ′. A channel-shaped steel beam 10, a plate-shaped sheer connector 20 bonded to the connecting plates 13 and 13 'of the channel-shaped steel beam 10 and having a plurality of holes 22 and 24 formed therein, and the channel Coupling reinforcing bar (25) for connecting the sheath connector (20) facing each other so as to restrain the spreading and warping of the steel beam (10) and the engaging key bonded to the bottom plate 11 of the channel steel beam (10) It consists of 30.

The channel-shaped steel beam 10 has a bottom plate 11 having a longer length than the width, both side wall plates 12 and 12 'integrally formed upward from both sides of the bottom plate 11, and the side wall plates. It consists of connecting plates 13 and 13 'integrally formed from (12, 12'), respectively. In FIG. 1, both side wall plates 12 and 12 ′ are bent upwardly perpendicular to the bottom plate 11, but may be bent inclinedly. Although the connecting plates 13 and 13 'are also shown to be bent to protrude outward from the ends of the side wall plates 12 and 12', they may be bent to protrude inward. On the other hand, the bottom plate 11, the side wall plates 12, 12 'and the connecting plate 13, 13' constituting the channel-shaped steel beam 10 is formed by bending a single steel sheet, or they are made of a separate steel sheet It can also be constructed by welding.

The channel-shaped steel beam 10 configured as described above becomes a formwork for placing concrete beams, and functions as a shear reinforcing steel reinforcement bar of reinforced concrete beams, and forms a composite beam that resists external force together with concrete filled inside. On the other hand, the connecting plates 13 and 13 'are used as pedestals of formwork or deck plates for slab concrete pouring.

The flat type sheath connector 20 joined to each of the connecting plates 13 and 13 'in parallel to the longitudinal direction of the channel-shaped steel beam 10 has a plurality of holes 22 in the steel plate 21 having a predetermined width and length. , 24, and the holes 22 and 24 may be formed as holes 22 or holes 24 closed at one side.

That is, as shown in FIG. 1, a hole 22 having one side open at the upper portion in the width direction is formed, and a hole 24 closed at the bottom is formed therein, or as shown in FIG. 2A, as shown in FIG. 2A. A hole 22 having one side open at the side may be formed, and a hole 24 closed at the side may be formed, or as shown in FIG. 2B, a hole 24 closed at the center portion of the width may be formed.

The holes 22 and 24 formed in this way can ensure the continuity of the concrete combined with the steel and wedging against horizontal and vertical shear forces to prevent the concrete from separating into layers. In particular, when one side of the open hole 22 is formed, the flat type sheath connector 20 leads to a more flexible behavior.

At this time, the flat type sheath connector 20 may be composed of a single member having the same length as the length of the channel-shaped steel beam 10 or divided into a plurality of.

The flat sheath connector 20 is a shear connector having superior rigidity and strength than the stud, and effectively resists the horizontal shear force generated at the interface between the connecting plates 13 and 13 'and the concrete slab interface, so that the composite beam behavior is more effective. . That is, when compared with the stud connector, which is a flexible connection member used as a conventional sheath connector, the structural resistance performance has the capability of a rigid shear connector, and the deformation capacity against the working load is a flexible shear connector. It will function as a semi-rigid shear connector (Semi-Rigid shear connector) showing the characteristics of.

The connecting reinforcing bar 25 is to restrain the spreading and twisting of the channel-shaped steel beam 10, and connects the sheer connector 20 opposite each other. That is, the connecting reinforcing bar 25 prevents the channel-type steel beam 10 from being widened or distorted due to the working load acting on the channel-shaped steel beam 10 and the side pressure of concrete filled in the channel-shaped steel beam 10. To ensure the stability of the beam cross section.

Engagement key 30 installed on the bottom plate 13 of the channel-shaped steel beam 10 is a plurality of holes 32 at predetermined intervals in the steel plate 31 having a predetermined width and length as shown in Figure 3a Perforations, and the diaphragm 34 is coupled perpendicularly to the longitudinal direction of the steel sheet 31 at predetermined intervals between the plurality of holes (32).

In this case, the reinforcement 36 may be further coupled to the hole 32 as illustrated in FIG. 3B, and both ends of the diaphragm 34 may be bent upward at right angles as illustrated in FIG. 3C. .

The engagement key 30 configured as described above not only increases the bonding force with the concrete placed inside the channel-shaped steel beam 10 but also controls tensile cracking occurring in the concrete. In particular, the diaphragm 36 is flexed under the beam concrete. The expansion of the tensile cracks caused by the tensile strain is very effective in restraining acupressure.

Figure 4 is a perspective view showing a steel permanent formwork beam according to another embodiment of the present invention. As shown, unlike the above-described embodiment, the steel permanent formwork according to the present embodiment does not connect the sheath connector 20 bonded to each connecting plate 13 and 13 'to each other by connecting reinforcing bars 25, The connecting plate 44 in which a plurality of holes 43 are perforated is welded on the connecting plates 13 and 13 'of the steel beam 10. Of course, in addition to the connecting plate 44 can be further coupled to the connecting reinforcement 25 of course.

The hole 43 drilled in the connecting plate 44 serves as a shear key, and the size of the hole 43 is the size of the coarse aggregate used for concrete mixing so that the concrete can be well filled inside the channel-shaped steel beam 10. The larger one is preferable, and the hole 43 may have various shapes such as a circle, a rectangle, and a triangle.

As the steel sheet constituting the connecting plate 44, a flat plate as shown in FIG. 4, a corrugated steel plate as shown in FIG. 5A, or a bone steel plate as shown in FIG. 5B may be selectively used. When manufacturing the connecting plate 44 using a corrugated steel sheet or a corrugated steel sheet, it is possible to expect an effect of increasing the adhesion to concrete.

Instead of the connecting plate 44, a wire mesh 46 as shown in FIG. 5C or a metallas 48 as shown in FIG. 5D may be used.

The connecting plate 44 or the wire mesh 46 or the metal lath 48 joined to the connecting plates 13 and 13 'of the channel-shaped steel beam 10 is the same as the connecting reinforcing bar 25 described above. The stability of the cross section of the beam can be secured by preventing the channel-shaped steel beams 10 from spreading or twisting due to the work load acting on the steel beams 10 and the lateral pressure of concrete filled in the channel-shaped steel beams 10. Make sure

Hereinafter, a method for forming a steel concrete composite beam using the steel permanent formwork beam according to the present invention configured as described above will be described with reference to FIGS.

First, the single steel sheet is bent to form the bottom plate 11, the side wall plates 12 and 12 'and the connecting plates 13 and 13', or they are formed of separate steel sheets and then welded to form the channel steel beam 10. To produce. Next, the engagement key 30 is welded to the bottom plate 11, the flat plate sheath connector 20 is welded to the connecting plates 13 and 13 ′, and then the opposite flat plate sheath connector 20 is connected to the rebar. (25) to each other, or by connecting the connecting plate 44, the wire mesh 46 or the metal lath 48 to the connecting plate (13, 13 ') to produce a steel permanent formwork beam. Next, bring the steel permanent formwork beam into the site and fix and install it in the design position. At this time, since the steel permanent formwork can be handled in the same way as the H-beams, the joining with other members (steel pillars, girders) uses a conventional method of joining steel members (bolt welding, welding welding) that is easy for field work.

After that, the slab formwork is placed on the connecting plates 13 and 13 'of the channel steel beam 10, and the beam concrete filled with the slab reinforcement 52 and 54 and filled in the channel steel beam 10 and If the slab concrete is poured and cured at the same time, the steel permanent formwork beam and the slab concrete are integrated.

At this time, when the deck plate is used instead of the slab formwork, as shown in Figure 7, the end of the deck plate 70 on the connecting plate (13, 13 ') of the channel-shaped steel beam 10 is connected By tightening the bolts to penetrate the plates 13 and 13 ′ and the deck plate 70, concrete pouring may be performed while restraining the movement of the deck plate.

Steel concrete composite beam completed in the above process does not need a separate formwork for the concrete placement of beams, and maintains a structurally stable joint relationship without the shear connection member of the beam and slab, the interior of the channel-shaped steel beam (10) The concrete filled in can be triaxially stressed and can exhibit greater strength.

As described above, according to the present invention, a phenomenon in which the channel cross section is opened by the vertical load is prevented, and the synthesizing effect between the steel and the concrete slab is improved.

In addition, the occurrence of slip between the concrete and the bottom plate filled in the steel permanent formwork beam is prevented, so that the steel part below the neutral axis reaches sufficient plastic deformation, thereby improving the ultimate resistance capacity and securing a certain level of ductility, so that the structural safety of the composite member It is effective to increase.

In addition, by properly arranging the connecting reinforcing bar or connecting plate is sufficient to restrain the concrete filled inside the steel permanent formwork beam, there is an effect that can exhibit excellent ductility in member behavior.

Although the present invention has been described in connection with the above-mentioned preferred embodiments, various modifications and variations are possible without departing from the spirit and scope of the invention. Thus, the claims will cover any modifications or variations that fall within the spirit of the invention.

Claims (12)

A bottom plate 11, both side wall plates 12 and 12 'integrally formed upward from both sides of the bottom plate 11, and a connecting plate 13 formed integrally from the both side wall plates 12 and 12', respectively. 13 '), the channel-shaped steel beam 10 composed of; Plate-shaped sheer formed with a plurality of holes 22 and 24 formed in the steel plate 21 having a predetermined length and width and joined to the connecting plates 13 and 13 'in parallel with the longitudinal direction of the channel-shaped steel beam 10. A connector 20; A plurality of connecting members joined perpendicularly to the longitudinal direction of the channel-shaped steel beams 10 so as to restrain the spreading and warping of the channel-shaped steel beams 10; A plurality of holes 32 are drilled in the steel plate 31 having a predetermined width and length and bonded to the bottom plate 11 of the channel-shaped steel beam 10 and attached at predetermined intervals between the plurality of holes 32. And an engagement key 30 coupled to the diaphragm 34 to increase the pressure restraint effect perpendicularly to the longitudinal direction of the steel plate 31. The method of claim 1, Holes 22 and 24 formed in the flat sheath connector 20 may include holes 22 formed at one end of the flat sheath connector 20 at one end in the width direction of the flat sheath connector 20 and a closed hole formed at the center portion in the width direction thereof. Steel permanent formwork, characterized in that it comprises a 24). The method according to claim 1 or 2, The connecting member is a steel permanent formwork, characterized in that the connecting reinforcing bar (25) connecting the flat sheer connector (20) facing each other. delete The method according to claim 1 or 2, The connecting member is joined to the connecting plate (13, 13 ') to cover the opening of the channel-shaped steel beam 10, the steel permanent form, characterized in that the connecting plate 44 perforated a plurality of holes (43). Bo. The method of claim 5, wherein In the bottom plate 11 of the channel-shaped steel beam 10, a plurality of holes 32 are drilled in a steel plate 31 having a predetermined width and length, and attached and acupressure at predetermined intervals between the plurality of holes 32. Steel permanent formwork, characterized in that the engagement key 30 is further bonded to the plate 34 to increase the restraining effect perpendicular to the longitudinal direction of the steel plate (31). The method of claim 6, The connecting plate 44 is a steel permanent formwork, characterized in that made of corrugated steel sheet or corrugated steel sheet. The method according to claim 1 or 2, The connecting member is a steel permanent formwork beam, characterized in that the wire mesh 46 or metallas 48 bonded to connect the connection plate (13, 13 ') of the channel-shaped steel beam (10) with each other. The method of claim 8, In the bottom plate 11 of the channel-shaped steel beam 10, a plurality of holes 32 are drilled in a steel plate 31 having a predetermined width and length, and attached and acupressure at predetermined intervals between the plurality of holes 32. Steel permanent formwork, characterized in that the engagement key 30 is further bonded to the plate 34 to increase the restraining effect perpendicular to the longitudinal direction of the steel plate (31). A bottom plate 11, both side wall plates 12 and 12 'integrally formed upward from both sides of the bottom plate 11, and a connecting plate 13 formed integrally from the both side wall plates 12 and 12', respectively. , 13 ') and a steel plate 21 bonded to each of the connecting plates 13 and 13' side by side in the longitudinal direction of the channel steel beam 10 and having a predetermined length and width. A flat sheer connector 20 having a plurality of holes 22 and 24 formed therein, and perpendicular to the longitudinal direction of the channel steel beam 10 so as to restrain the spreading and warping of the channel steel beam 10. Steel permanent formwork beam comprising a plurality of connecting members to be bonded; Steel concrete composite beam, characterized in that the steel permanent form beams are filled with in-site casting, the steel permanent form beams (1) and the concrete behaves synthetically. The method of claim 10, The connecting member is a connecting plate (44), a wire mesh bonded to the connecting reinforcing bar 25 or connecting plates (13, 13 ') of the channel steel beam (10) for connecting the flat plate-shaped sheath connector (20) Steel concrete composite beam, characterized in that any one of (46) or metal lath (48). The method of claim 11, In the bottom plate 11 of the channel-shaped steel beam 10, a plurality of holes 32 are drilled in a steel plate 31 having a predetermined width and length, and attached and acupressure at predetermined intervals between the plurality of holes 32. Steel concrete composite beam, characterized in that the engagement key 30 is further bonded to the plate 34 to increase the restraining effect perpendicular to the longitudinal direction of the steel plate (31).

Images