WO2013069948A1

WO2013069948A1 - Shear reinforcement for reinforced concrete structure

Info

Publication number: WO2013069948A1
Application number: PCT/KR2012/009286
Authority: WO
Inventors: 이재호
Original assignee: (주)세종알앤디
Priority date: 2011-11-08
Filing date: 2012-11-06
Publication date: 2013-05-16
Also published as: KR20130050634A; US20150240493A1; BR112014011000A2; DE112012004226T5

Abstract

The present invention provides a shear reinforcement for a reinforced concrete structure which may be installed within a reinforced concrete structure after the installation of reinforcing bars during construction, in order to increase resistance against shear failure. The shear reinforcement (10) for the reinforced concrete structure includes a reinforcement bracket (20) and a connecting bar (40), wherein the reinforcement bracket (20) is disposed in a fixed number along a lengthwise direction thereof, and the connecting bar (40) is parallelly disposed in a lengthwise direction of the connecting bar (40) and fixed on each of upper anchor heads (22) of a plurality of the reinforcement brackets (20). The shear reinforcement (10) for the reinforced concrete structure according to the present invention may maximize the shear reinforcing performance of a shear reinforcement proposed by this inventor through a prior application and improve the convenience of work.

Description

Shear reinforcement for reinforced concrete structures

The present invention relates to a shear reinforcement for reinforced concrete structures, and more specifically, to be installed in a reinforced concrete structure to increase the resistance to shear destruction so that the installation of the shear reinforcement after completing the reinforcement work during construction Shear reinforcement for reinforced concrete structures.

In reinforced concrete structures constructed through the application of rebar and concrete, slabs, girders and beams, columns, walls and corbels need to increase shear strength. Therefore, it is constructed by applying a shear reinforcement for reinforcement of shear performance.

The inventors of the Republic of Korea Patent Registration No. 10-0971736 "method of applying a stirrup (strip reinforcing bar) through a" shear reinforcement having a double anchorage function each up and down, "a method of applying a shear stud (shear stud) And a shear reinforcement for reinforced concrete structures to overcome the problems of the method of applying a shear band (shear band) has been proposed.

As described above, the shear reinforcing material proposed by the present invention has a structure in which the anchor head is installed on the upper and lower sides of the truss formed by connecting the upper chord and the lower chord with a connecting member such as a vertical or inclined rod. Since the double anchorage function is performed at, and the double anchorage function is provided at the bottom by the lower anchor head and the lower chord, the shear resistance and the ductility performance can be expected as compared with the aforementioned technologies.

Therefore, the present invention is proposed to increase the utilization of the shear reinforcing material for the reinforced concrete structure proposed by the present inventors in this way to further increase its utilization.

Therefore, the present invention has been proposed to meet such a necessity, and is installed in a reinforced concrete structure to increase the resistance to shear destruction in a new form to install the shear reinforcement after completing the reinforcement work during construction It is an object of the present invention to provide shear reinforcement for reinforced concrete structures.

In particular, the present invention is the reinforcement work during construction while maintaining the advantages of the shear reinforcement for reinforced concrete structures proposed by the inventor through the Republic of Korea Patent Registration No. 10-0971736 "shear reinforcement each having a double anchorage function up and down" It is an object of the present invention to provide a shear reinforcement for a new type of reinforced concrete structure that enables the installation of shear reinforcement after completion of the test.

According to a feature of the present invention for achieving the above object, the slab (girder, baem), column (column), wall (wall), cobel (corbel) and is constructed through the application of reinforcing steel and concrete The upper anchor head (22) in a shear reinforcement for reinforced concrete structures, which is installed inside a reinforced concrete structure such as a foundation to increase shear resistance of concrete to increase resistance to shear failure of concrete. And a reinforcing bracket (20) having a lower anchor head (24) and a connecting plate (26) for vertically fixing the upper anchor head (22) and the lower anchor head (24); A connecting bar 40 fixed on the upper anchor head 22 of the reinforcing bracket 20; The reinforcing bracket 20 is arranged in a number determined in the longitudinal direction of the connecting bar 40, the connecting bar 40 is arranged horizontally in the longitudinal direction of each upper anchor head of the plurality of reinforcing brackets 20 It is fixed on (22).

In the shear reinforcement for reinforced concrete structures according to the present invention, the horizontal cross-sectional area A1 of the upper anchor head 22 and the lower anchor head 24 is 10 times greater than the horizontal cross-sectional area A2 of the connecting plate material 26. It can have a larger size.

In the shear reinforcement for the reinforced concrete structure according to the present invention, the upper anchor head 22, the lower anchor head 24 and the connecting plate 26 is a flat metal plate 22 ', 24', 26 ' ) May be fused through welding to form the reinforcing bracket 20.

In such a shear reinforcement for reinforced concrete structures according to the present invention, the connecting plate 26 may be a ratio of the width and thickness more than five times.

According to the shear reinforcement for reinforced concrete structures according to the present invention, since the shear reinforcement of the present invention has a structure that is inserted into the reinforcement, the shear reinforcement (10) can be installed after completion of the reinforcement work during construction of the reinforced concrete structure of the work Convenience can be increased. In particular, the shear reinforcement for the reinforced concrete structure according to the present invention is made by applying the structure of the shear reinforcement proposed by the present inventors through the application, to maximize the shear reinforcement performance to increase the convenience of work.

1 is a view for explaining a shear reinforcement for reinforced concrete structures according to the spirit of the present invention;

2 is a perspective view of a shear reinforcement for reinforced concrete structures according to a preferred embodiment of the present invention;

3 is a cross-sectional view taken along the line AA ′ in FIG. 2;

Figure 4 is a view for explaining a preferred manufacturing form of the reinforcement bracket in shear reinforcement for reinforced concrete structures according to the present invention;

5 is a view for explaining the characteristics of the upper and lower anchor head according to a preferred embodiment of the present invention;

Figure 6 is a view for explaining in detail a dedicated spacer for securing the concrete coating thickness in the shear reinforcement for reinforced concrete structures according to the present invention;

7 is a view showing a construction method of a shear reinforcement for reinforced concrete structures according to a preferred embodiment of the present invention;

8 is a view for explaining a shear reinforcement for reinforced concrete structures according to another embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, FIGS. 2 to 8, and like reference numerals denote like elements for performing the same functions in FIGS. 1 to 8. On the other hand, in each drawing, the technical construction and action generally related to the shear reinforcement of reinforced concrete structures, and the technology for constructing slabs and pillars using the same, and the techniques that are easily applied by those in this field from related technologies in this field. Detailed description will be omitted. In addition, although the size ratio between elements is somewhat different in the drawings of the drawings, or the size between the parts that are coupled to each other is expressed differently, the representation differences in such drawings are easily understood by those skilled in the art. The descriptions are omitted since they are possible parts.

Figure 2 is a perspective view of a shear reinforcement for reinforced concrete structures according to a preferred embodiment of the present invention, Figure 3 is a cross-sectional view taken along the line A-A 'in Figure 2, Figure 4 is a reinforced concrete structure according to the present invention Figure 5 is a view for explaining a preferred manufacturing form of the reinforcing bracket in the shear reinforcement for, Figure 5 is a view for explaining the features of the upper and lower anchor head according to a preferred embodiment of the present invention, Figure 6 is in accordance with the present invention In the shear reinforcement for reinforced concrete structures is a view for explaining in detail a spacer for securing the concrete cover thickness. And, Figure 8 is a view for explaining a shear reinforcement for reinforced concrete structures according to another embodiment of the present invention.

2, the shear reinforcement 10 for the reinforced concrete structure according to a preferred embodiment of the present invention consists of a reinforcing bracket 20, connecting bar 40 and the spacer 50 through the application of the reinforcement and concrete It is installed inside reinforced concrete structures such as slabs, girders, baems, columns, walls, corbels, and foundations to increase shear resistance of concrete. Increase the resistance to shear failure of concrete.

At this time, the reinforcing bracket 20 has an upper anchor head 22 and a lower anchor head 24, and has a connecting plate material 26 for fixing the upper anchor head 22 and the lower anchor head 24 vertically. The reinforcing brackets 20 are arranged in a number determined in the longitudinal direction of the connecting bar 40.

4, the reinforcing bracket 20 in the shear reinforcement 10 for the reinforced concrete structure according to the present embodiment is formed by welding the square plate 22 ', 24', 26 'of a flat metal material. That is, as shown in (a) of FIG. 4, in the present embodiment, the upper anchor head 22, the lower anchor head 24, and the connecting plate 26 of the reinforcing bracket 20 are flat metal square plates 22 ′. , 24 'and 26'), and as shown in FIG. 4 (b), they are fused to each other by welding to form a reinforcing bracket 20. Of course, as shown in FIG. 8, the upper anchor head 22, the lower anchor head 24, and the connecting plate material 26 have holes 60 and protrusions 61 to increase the attachment force with other concrete or concrete. ) May be formed by processing.

Such a structure of the reinforcing bracket 20 according to the present embodiment lowers the manufacturing cost by applying a plate material which is generally sold in various standards, and facilitates the manufacturing by not applying a separate special processing or molding method. .

Referring again to FIG. 2, in the shear reinforcement 10 for reinforced concrete structures according to a preferred embodiment of the present invention, the connecting bar 40 is fixed on the upper anchor head 22 of the reinforcing bracket 20. The connecting bars 40 are horizontally arranged in the longitudinal direction to be fixed on each upper anchor head 22 of the plurality of reinforcing brackets 20.

In this embodiment, the connecting bar 40 uses a flat rectangular plate in the same manner as the manufacturing of the above-described reinforcing bracket 20, and is made to be fixed to the reinforcing bracket 20 by welding, thereby making the manufacture convenient and manufacturing. Make the unit price lower.

On the other hand, as shown in Figure 8, the connecting bar 40 in the shear reinforcement 10 for the preferred reinforced concrete structure of the present invention may be configured by applying various numbers and fastening method under the spirit of the present invention. For example, FIG. 8 shows a connecting bar 40 in which two plates 40 ', 40 "are disposed on the upper anchor head 22 of the reinforcing bracket 20 in parallel with each other and fixed as bolts 42. The connecting bar 40 is horizontally disposed in the longitudinal direction so that various forms can be applied under the technical idea of the present invention to be fixed on each upper anchor head 22 of the plurality of reinforcing brackets 20. It is.

In addition, as shown in Figure 3, the shear reinforcement 10 for the reinforced concrete structure according to the present embodiment is the horizontal cross-sectional area (A1) of the upper anchor head 22 and the lower anchor head 24 is the connecting plate material 26 It is preferable to have a size larger than 10 times larger than the horizontal cross-sectional area (A2) of the connection, and the connecting plate member 26 has a width and thickness ratio of 5 times or more. The strength of the proposed structure (maximum shear reinforcement is maximized because the vertical shear reinforcement is reinforced to the entire range except the concrete cover thickness) through the "shear reinforcement with double anchorage function up and down". .

More specifically, the shear reinforcement 10 for reinforced concrete structures according to a preferred embodiment of the present invention, the inventors of the Republic of Korea Patent Registration No. 10-0971736 "shear reinforcement having a double anchorage function each up and down" It is characterized in that the rectangular plate structure (Fig. 10 (a)) applied to the various types of anchor head proposed in the. Such a square plate structure allows the upper and

lower anchor heads

22 and 24 and the connecting plate 26 to have the same width B in one direction (the longitudinal direction of the connecting bar 40) in this embodiment (Fig. 5 ( b)}. At this time, the connecting plate member 26 has a width and thickness ratio of at least 5 times, and the horizontal cross-sectional area A1 of the upper and

lower anchor heads

22 and 24 is 10 times larger than the horizontal cross-sectional area A2 of the connecting plate material 26. By forming to have the above size, to ensure a sufficient anchorage effect. Restrictions on the cross-sectional area of the upper and

lower anchor heads

22 and 24 are described by Abdel-Salam Mokhtar, Amin Ghali and Walter Dilger et al. 82-60 "Stud Shear Reinforcement for Flat Concreate Plates" applies the proportional relation of the cross-sectional area proposed as the most suitable of stud and stem to the present invention. According to the results of a long study, it was confirmed through experiments that the lower the pressure stress acting on the inside of the anchor head, in particular, the circumference of the stem in contact with the anchor head, the better the effect of the shear stiffener.

Referring to FIG. 5, the shear reinforcement 10 for the reinforced concrete structure according to the present embodiment provides a more improved shear reinforcement effect than the stud method. That is, the stud method is a circular bar, when the diameter is D, the circumferential length of contact with the anchor head is? This circumferential length is automatically determined by the diameter D and cannot be increased further. On the other hand, the shear reinforcing material 10 according to the present invention is a thin plate when the width of the connecting plate member (26, stem) B, the circumferential length in contact with the anchor head is 2B. Therefore, even when the stud method and the shear stiffener according to the present invention have the same cross-sectional area (A), the shear stiffener 10 according to the present invention further increases the shear stiffening effect by reducing the thickness t and increasing the width B to increase the circumferential length. It can be. In addition, in the stud method, the lower part of the head is formed at an angle greater than 90 degrees with the stem, but the shear reinforcement material according to the present invention forms 90 degrees, so that acupressure stress is lower than that of the study method even when subjected to the same force. Shear reinforcement effect is improved. That is, in the stud method, when the force P acts inside the anchor head, the bearing pressure R acting on the concrete increases as R = P / cosθ. However, in the present invention, when the force P acts on the inside of the anchor head, the ground force (R) acting on the concrete is characterized by the lower ground pressure than the stud method because the same force acts as R = P.

Referring back to FIG. 2, the shear stiffener 10 for the reinforced concrete structure according to the preferred embodiment of the present invention includes a spacer 50 formed to be easily coupled to the lower anchor head 24 of the reinforcing bracket 20. By using it, even if the worker installs the shear reinforcement without paying attention to the concrete coating thickness is automatically maintained so that the construction air can be shortened while effectively improving the construction quality.

Referring to FIG. 6, in the shear reinforcement 10 for the reinforced concrete structure according to the present embodiment, the spacer 50 includes a support plate 52, a locking hook 54, and a height protrusion 56. At this time, the hook hook 54 is disposed on both sides of the support plate 52 to be coupled to the lower anchor head 24 while forming a space 51 into which the lower anchor head 24 of the reinforcing bracket 20 is inserted. Is formed. And, the height projection 56 is formed to extend to the lower side of the support plate 52, as shown in Figure 7, so that the shear reinforcing material 10 can ensure the required concrete coating thickness.

7 is a view showing a construction method of a shear reinforcement for reinforced concrete structures according to a preferred embodiment of the present invention.

Referring to Figure 7 how the shear stiffener 10 according to a preferred embodiment of the present invention is used in a concrete structure (slab), first, as shown in Figure 7 (a), the lower main root (2) and the vicinity ( 3) is to be installed, in which the spacer (1) is usually bonded to the bottom of the reinforcing bar at regular intervals in order to secure the concrete coating thickness of the rebar. Of course, the shear reinforcing material 10 according to the present invention, as described above, by installing a dedicated spacer 50, the concrete coating thickness is set immediately to make the operation convenient. As shown in FIG. 7B, the upper main bar 4 and the vicinity 5 are provided in the same manner as in the normal back muscle work. And, as shown in Figure 7 (c), the shear reinforcing material 10 for the reinforced concrete structure according to a preferred embodiment of the present invention is placed between the reinforcement. At this time, since the shear reinforcing material 10 according to the present embodiment is naturally placed in the required position by the spacer 50, the worker does not need to perform other operations to secure the concrete coating thickness of the upper reinforcing bar.

Shear reinforcement for reinforced concrete structures according to a preferred embodiment of the present invention as described above, but shown in accordance with the above description and drawings, but this is only described for example and within the scope without departing from the spirit of the invention It will be appreciated by those skilled in the art that various changes and modifications are possible.

1 is a view for explaining a shear reinforcement for reinforced concrete structures according to the spirit of the present invention.

Referring to Figure 1, the shear reinforcing material 10 for the reinforced concrete structure according to the present invention is made of a reinforcing bracket 20 and the connecting bar 40, the reinforcing bracket 20 is the longitudinal direction of the connecting bar 40 The connecting bar 40 is arranged horizontally in the longitudinal direction and is fixed on each upper anchor head 22 of the plurality of reinforcing brackets 20, so that the connecting bar 40 is constructed through the application of reinforcing bars and concrete. It is installed inside reinforced concrete structures such as slabs, girders, baems, columns, walls, corbels and foundations to increase shear resistance of concrete. To increase the resistance to shear failure.

At this time, the reinforcing bracket 20 has an upper anchor head 22 and the lower anchor head 24, the connecting plate member 26 for fixing the upper anchor head 22 and the lower anchor head 24 vertically; Stem). And, the connecting bar 40 is fixed on the upper anchor head 22 of the reinforcing bracket 20. Of course, the connecting plate 26 may be fixed at any angle with the upper and lower anchor heads 22 and 24 as necessary.

Since the shear reinforcement 10 for the reinforced concrete structure according to the present invention has an open structure in the downward direction, it has an advantage that can be installed after the reinforcement work is made. That is, in the case of using the conventional shear reinforcing material proposed by the present inventors (Korean Patent Registration Publication No. 10-0971736 "shear reinforcing material having a double anchorage function each up and down"), the work order in the field of the formwork for the construction of the slab After construction, the lower main bar and the vicinity are installed, the shear reinforcement is installed on the lower bar, and the upper main bar and the vicinity. On the contrary, the shear reinforcement 10 for the reinforced concrete structure according to the present invention has a work method of installing the shear reinforcement 10 after the lower and upper reinforcement work, as shown in FIG. 7.

Therefore, the shear stiffener 10 for the reinforced concrete structure according to the present invention to maximize the shear reinforcement performance of the shear stiffener proposed by the present inventors to increase the convenience of work.

Claims

Shear strength of concrete, installed inside reinforced concrete structures such as slabs, girders, baems, columns, walls, corbels, and foundations In the shear reinforcement for reinforced concrete structures to increase the shear resistance to increase the resistance to shear failure of the concrete,

A reinforcing bracket (20) having an upper anchor head (22) and a lower anchor head (24), and a connecting plate (26) for vertically fixing the upper anchor head (22) and the lower anchor head (24);

A connecting bar 40 fixed on the upper anchor head 22 of the reinforcing bracket 20;

The reinforcing bracket 20 is arranged in a number determined in the longitudinal direction of the connecting bar 40, the connecting bar 40 is arranged horizontally in the longitudinal direction of each upper anchor head of the plurality of reinforcing brackets 20 Shear stiffener for reinforced concrete structures, characterized in that fixed on (22).
The method of claim 1,

Horizontal cross-sectional area (A1) of the upper anchor head 22 and the lower anchor head 24 has a size 10 times larger than the horizontal cross-sectional area (A2) of the connecting plate 26 for the reinforced concrete structure Shear stiffeners.
The method according to claim 1 or 2,

The upper anchor head 22, the lower anchor head 24 and the connecting plate member 26 is made of a flat metal square plate (22 ', 24', 26 '), and welded to each other by welding the reinforcement bracket Shear reinforcement for reinforced concrete structures, characterized in that to form (20).
The method of claim 3, wherein

The connecting plate 26 is a shear reinforcement for reinforced concrete structures, characterized in that the ratio of the width and thickness more than five times.