Grid-type drop-panel structure, and a construction method therefor

A latticing drop panel structure includes a plurality of columns (100 or 101) or walls, and a connecting member (210) including a concrete drop panel (219) having a cross-section area larger than that of the column (100 or 101) or the wall, wherein the connecting member (210) having four unit rods 212, surrounded around the drop panel (219) in a latticing form, wherein the unit rods (212) are parallel with the respective sides of the column and cross at the same level, whereby sagging displacement of the slab is reduced due to the existence of the drop panel.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a national stage application under 35 U.S.C. 371 of PCT Application No. PCT/KR2009/000765 having an international filing date of 18 Feb. 2009, which designated the United States, which PCT application claimed the benefit of Korean Patent Application Nos. 10-2008-0014548 filed Feb. 18, 2008, and 10-2009-0013414 filed on Feb. 18, 2009, the entire disclosure of each of which are hereby incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a latticing drop panel structure and a constructing method thereof.

BACKGROUND ART

FIG. 1is a front view illustrating the installation structure of a column and a girder or a slab according to the related art.

The installation structure ofFIG. 1includes columns10set up at regular intervals, girders or slabs20connected between the adjacent columns10.

The girder or slab20is directly connected to the center or side of the column10, and the connected girder or slab sags under the weight or load of an installation (not shown) placed thereon.

According to a standard diagram handbook of machine design, uniformly distributed load can be calculated by the following formula.
δmax=5wL4/384EI

where δmax: a quantity of maximum sagging

I: secondary moment of area

The quantity of maximum sag (δmax) is proportional to the fourth square of the whole length L of the girder or slab.

InFIG. 1, the whole length L corresponds to an effective length l of the girder or slab20between the columns10where sagging occurs, and the maximum sagging (δmax) corresponds to bent displacement e that is the length of sagging at the center of the girder or slab20.

However, in such installation structures, the effective length l of the girder or slab20is too long, so that the sag occurring on the girder or slab20. To avoid this problem, a girder or slab20, the secondary moment I of area of which is high, should be used Thus, a girder or slab20with larger thickness and size is required, which problematically increases the cost of the girder or slab greatly.

DISCLOSURE

Technical Problem

The present invention is directed to drop panel structures in which the thickness or size of a girder or slab is not large, while bending displacement of the girder or slab is small, and a constructing method thereof.

Technical Solution

In order to accomplish the above object of the present invention, according to an aspect of the present invention, the latticing drop panel structure includes a plurality of columns (100or101) or walls; and a connecting member (210) including a concrete drop panel (219) having a cross-section area larger than that of the column (100or101) or the wall, in which the connecting member (210) have four unit rods212, surrounded around the drop panel (219) in a latticing form, in which the unit rods (212) are parallel with the respective sides of the column and cross at the same level.

In an exemplary embodiment, the column (100or101) may include reinforced concrete or steel-framed reinforced concrete, the connecting member (210) may be composed of H-section steel, and the unit rod (212) may have a connecting end (600or680), a cross-section area of which is larger at an upper side than at a lower side.

In an exemplary embodiment, a slant tension member (410OR412) may be coupled to the connecting member (210) in the same or slant direction as or from the connecting member (210), the unit rod (212) may be a reinforced concrete beam (700) or a steel beam (800) in which a plurality of main reinforcement steel (710) is coiled with stirrups (712).

According to another aspect of the present invention, the method of constructing latticing drop panel structures includes the steps of: installing a connecting member (210) in places on the respective floors of a plurality of reinforced concrete columns (100) or walls, the connecting member having an internal space (214), the cross-section area of which is larger than that of the column (100) or wall; connecting a linear member (220) to the plurality of connecting members (210); installing an upper horizontal mold (320) between the linear members (220); and pouring concrete into the internal space (214) and onto the upper horizontal mold (320) to form a drop panel (219) and a slab structure.

According to a further aspect of the present invention, the method of constructing latticing drop panel structures includes the steps of: installing a plurality of vertical molds (102) shaped like a reinforced concrete column (100) or wall; installing a connecting member (210) in places on the respective floors of the vertical mold (102), the connecting member having an internal space (214), the cross-section area of which is larger than that of the column (100) or wall; pouring concrete into the vertical mold (102); connecting a linear member (220) to the plurality of connecting members (210); installing an upper horizontal mold (320) between the linear members (220); and pouring concrete into the internal space (214) and onto the upper horizontal mold (320) to form a drop panel (219) and a slab structure.

According to still another aspect of the present invention, the method of constructing latticing drop panel structures includes the steps of: installing a plurality of vertical molds (102), shaped like a reinforced concrete column (100) or wall; installing a connecting member (210) in places on the respective floors of the vertical mold (102), the connecting member having an internal space (214), the cross-section area of which is larger than that of the column (100) or wall; connecting a linear member (220) to the plurality of connecting members (210); installing an upper horizontal mold (320) between the linear members (220); and pouring concrete into the internal space (214) and onto the upper horizontal mold (320) to form a drop panel (219) and a slab structure in connection with the column (100) or wall.

According to yet another aspect of the present invention, the method of constructing latticing drop panel structures includes the steps of: installing a plurality of section steel (400), used in a steel-framed reinforced concrete column (101), in a vertical manner; installing a connecting member (210) in places on the respective floors of the section steel (400), the connecting member having an internal space (214), the cross-section area of which is larger than that of the column (101); connecting a linear member (220) to the plurality of connecting members (210); installing a vertical mold (102) shaped like the column (101); installing an upper horizontal mold (320) between the linear members (220); pouring concrete into the vertical mold (102) to form the column (101); and pouring concrete into the internal space (214) and onto the upper horizontal mold (320) to form a drop panel (219) and a slab structure.

In an exemplary embodiment, a coupling section (218) may be embedded in the reinforced concrete column (100) to connect the connecting member (210) and the column (100) to each other; the connecting member (210) may be composed of four unit rods (212) crossed into a latticing form with the internal space (214) formed at the center of the latticing form.

In an exemplary embodiment, a lower horizontal mold (330) may be installed on a lower side of the internal space (214), and the connecting member (210) and the vertical mold (102) may be fastened by a bolt.

Advantageous Effects

As set forth above, according to exemplary embodiments of the invention, bending displacement occurring due to sagging of the linear member or the slab can be reduced by the structure of connecting member including the drop panel.

Further, installation of the horizontal mold on the lower side of the internal space enables the pouring of concrete into the internal space, and the internal space may be defined by four unit rods.

Furthermore, by the structure of latticed connecting member, sagging of the slab can be maximally restricted, while the drop panel (219) does not have to be made greater, thereby saving the constructing cost and making the best use of the technical benefits.

MODE FOR INVENTION

Description will now be made of exemplary embodiments of the present invention with reference to the accompanying drawings. Throughout this document, reference should be made to the drawings, in which the same reference numerals and signs are used throughout the different drawings to designate the same or similar components. In the following description of the present invention, detailed descriptions of known functions and components incorporated herein will be omitted when they may make the subject matter of the present invention unclear.

FIGS. 2(a) and2(b) are front views illustrating the installation structures of columns and girders according to an embodiment, in whichFIG. 2(a) shows the case that a girder and a slab all are provided by a linear member, andFIG. 2(b) shows the case that only a slab is provided by a linear member.

In the constructing method of drop panel structures as shown inFIG. 2, the installation structures include a plurality of columns100set up at regular intervals, and coupling girders or slabs200connected between the columns100.

The coupling girder or slab200includes a connecting member210and a linear member220as a girder or slab, provided between the connecting members210.

The connecting member210includes a drop panel, which is formed by pouring concrete into the connection members as described below, and the drop panel is integrally formed with the column100and serves to enlarge the area of the column100, so that the amount of sagging of the connecting member becomes smaller than that of the linear member220on the coupling girder or slab200.

Thus, the whole length L1of the coupling girder or slab200becomes different from the effective length L2along which sagging occurs, such that the effective length L2is smaller than the whole length L1, thereby reducing the sagging displacement E.

Accordingly, unlike the conventional technology, there is no need to enlarge the thickness or size of the linear member220in order to increase the secondary moment of area of the linear member220.

A method of constructing the drop panel structures including the coupling girder or slab200will now be described.

First, a first embodiment method of constructing the drop panel structures is as follows.

FIG. 3is a flow chart illustrating a procedure of the first embodiment method of constructing the drop panel structures,FIG. 4is a perspective view illustrating a mold for a column,FIG. 5is a perspective view illustrating the mold ofFIG. 4into which concrete is poured, andFIG. 6is a perspective view illustrating the state in which a connecting member is fastened to the column in the course of constructing steps of the drop panel structures.

In the first step S110, the plurality of vertical molds102is installed as shown inFIG. 4.

In the second step S120, concrete104is poured into the vertical mold102as shown inFIG. 5.

Through the pouring of the concrete104into the vertical mold102, the reinforced concrete column100is formed.

In the third step S130, the connecting member210is installed in places of the respective floors of the plurality of reinforced concrete columns100, in which the connecting member has an internal space214, the cross-section area of which is larger than that of the column100.

Here, the column100is provided with a plurality of reinforcing rods110, which protrude upwards from the column.

Further, the column100may be replaced with a wall body, and in this case, the cross-section area of the column corresponds to that of the wall body.

Meanwhile, while the embodiment illustrated that the unit rod212of the connecting member210is H-section steel, a variety of section steels, including I-section steel, T-section steel, and the like, can be used as needed. However, since the H-section steel has the largest secondary moment of area per section area among the diverse kinds of section steels, the H-section steel is most preferably used to maintain high rigidity.

FIG. 7is a perspective view illustrating the connecting member ofFIG. 6.

As shown inFIG. 7, the connecting member210may have two or more kinds of shapes. First, as shown inFIG. 7(a), the connecting member210is formed into a latticing form, in which the four unit rods212cross each other so that the internal space214is formed in the center of the latticing form with a “+” type coupling rod216provided therein. The coupling rod216is installed only if needed, if it is not installed, a mold is installed on the lower side of the connecting member210and thus is placed on the upper end of the column100.

If needed, all of the coupling rods216may also be replaced with the mold.

Second, as shown inFIG. 7(b), the connecting member210is formed into a circular form using a circular rod221so that the internal space214is formed in the center with a “+” type coupling rod216provided therein.

It should be noted that since the cross-section area of the internal space214is larger than that of the column100, if the coupling rod216is placed on the upper end of the column100, the unit rod212or the circular rod221is separated from the column100.

If needed, the connecting member210may be of a shape such as a lozenge or a polygon, the coupling rod216may also be of other shape than the “+” shape.

FIG. 8is a perspective view illustrating the state in which a linear member is connected between the connecting members ofFIG. 6,FIG. 9is a perspective view illustrating the state in which a horizontal mold is installed in the construction ofFIG. 8, andFIG. 10is a perspective view illustrating the state in which reinforcing rods are additionally placed in the construction ofFIG. 9.

In the fourth step S140, the linear member220is connected to the plurality of connecting members210as shown inFIG. 8.

Specifically, the linear member220is connected between adjacent unit rods212of the connecting member210.

If needed, only the upper horizontal mold320is installed between the connecting members210without providing the linear member220.

The connection between the unit rod212of the connecting member210and the linear member220is performed by means of a connecting plate232and a plurality of bolts and nuts using a conventional manner, so a detailed description thereof will be omitted.

In the fifth step S150, the upper horizontal mold320is installed between the linear members220as shown inFIG. 9.

In the sixth step S160, a lower horizontal mold330is installed on the lower side of the internal space214, and reinforcing rods341are placed on the upper horizontal mold320and the lower horizontal mold330.

If needed, the fifth step S150and the sixth step S160may implemented concurrently.

FIG. 11is a perspective view illustrating the state in which concrete is poured into the construction ofFIG. 10, andFIG. 12is a vertical sectional view illustrating the part of the column ofFIG. 11.

In the seventh step S170, concrete is poured into the internal space214and onto the upper horizontal mold320to form a drop panel219and a slab structure500as shown inFIGS. 11 and 12.

That is, through the seventh step S170, as shown inFIG. 12, the drop panel219is formed in the internal space214, and the slab structure500is provided on the upper horizontal mold320.FIG. 12(a) shows the construction in which the linear member220is provided, andFIG. 12(b) shows the construction in which the linear member220is not provided.

By the seventh step S170, construction on one floor is completed.

Examining the vertical sections of the column100, the connecting member210, and the linear member220after the construction on one floor is completed via the seventh step S170, as shown inFIGS. 2 and 12, the concrete is poured into the internal space214of the connecting member210, the concrete drop panel219has the tensile strength much stronger than that of the linear member220or the slab structure500, which are iron framed.

Thus, sagging is mainly applied to only a portion of the linear member220or the slab structure500provided between the connecting members210, the length thereof is reduced by the amount of the connecting member210protruding from the circumference of the column100, so that bending displacement E occurring on a portion of the linear member220and the slab structure500between the connecting members210due to sagging is reduced.

According to the invention, due to the existence of the drop panel219, the linear member220, or the slab structure500, provided between the connecting members210, is partially reduced in length, having the effect of reducing sagging displacement that occurs on a portion of the linear member220or the slab structure500due to sagging, while the linear member220or the slab structure500is of small thickness and size.

Further, the installation of the lower horizontal mold330on the lower side of the internal space214enables the pouring of the concrete into the internal space214, the four unit rods212advantageously define the internal space214, and the coupling rod216allows the connecting member210to be placed on the respective floors of the column100.

When the connecting member210is placed on the upper end of the column100, the coupling rod216is coupled with the column100using a coupling section218, a lower portion218of which is embedded into the reinforced concrete column100as shown inFIG. 12, in the course of pouring concrete into the vertical mold102as shown inFIG. 5.

Further, an upper portion233of the coupling section218, which is not embedded into the reinforced concrete column100, is fastened to the coupling rod216by means of bolt-coupling

A second embodiment method of constructing the drop panel structure will now be described.

FIG. 13is a flow chart illustrating a procedure of the second embodiment method of constructing the drop panel structure,FIG. 14is a horizontal sectional view illustrating the state in which the connecting members are installed in places on the respective floors of the mold for a column, andFIG. 15is a horizontal sectional view illustrating the state in which concrete is poured into the mold for a column ofFIG. 14.

In the first step S210, the plurality of vertical molds102is installed as shown inFIG. 4, a step which is identical to the first step S110of the first embodiment.

In the second step S220, the connecting member210is installed on the respective floors of the vertical mold102as shown inFIG. 14, the connecting member having the internal space214, the cross-section area of which is larger than that of the column100. The column100may be replaced with a wall body, and in this case, the cross-section area of the column100corresponds to that of the wall body.

In the third step S230, concrete104is poured into the vertical mold102as shown inFIG. 15.

Subsequent steps after the fourth step S240of the second embodiment are identical to the fourth to seventh steps S140to S170of the first embodiment.

Thus, the second embodiment is different from the first embodiment in that after the first step S210, unlike the second step S120of the first embodiment, the second step S220is conducted to install the connecting member210on the respective floors of the vertical mold102, without pouring the concrete into the vertical mold102, and then the third step S230is conducted to pour the concrete into the vertical mold102.

A third embodiment method of constructing the drop panel structure will now be described.

FIG. 16is a flow chart illustrating a procedure of the third embodiment method of constructing the drop panel structure,FIG. 17is a horizontal sectional view illustrating the state in which the connecting members and the linear members are installed in places on the respective floors of the mold for a column, andFIG. 18is a horizontal sectional view illustrating the state in which a horizontal mold is installed in the construction ofFIG. 17.

In the first step S310, the plurality of vertical molds102, shaped like the reinforced concrete column100or wall body, is installed as shown inFIG. 4, a step which is identical to the first steps S110and S210of the first and second embodiments.

In the second step S320, the connecting member210is installed on the respective floors of the vertical mold102as shown inFIG. 14, the connecting member having the internal space214, the cross section of which is larger than that of the column100or wall body.

In the third step S330, the linear member220is connected to the plurality of connecting members210as shown inFIG. 17, a step which is different from the fourth step S140of the first embodiment in that the concrete is not poured into the vertical mold102.

If needed, only the upper horizontal mold320for forming a slab between the connecting members210may be installed as follows.

Meanwhile, the fourth step S340is conducted to install the upper horizontal mold320between the linear members220as shown inFIG. 18, a step which is different from the fifth step S150of the first embodiment in that the concrete is not poured into the vertical mold102.

In the fifth step S350, the lower horizontal mold330is installed on the lower side of the internal space214, and the reinforcing rods341are placed on the upper horizontal mold320and the lower horizontal mold330as shown inFIG. 18, through which the construction obtained is expressed as shown inFIG. 10, if the column100is replaced with the vertical mold102.

The sixth step S360is conducted to pour concrete into the vertical mold102, the internal space214, and the upper horizontal mold320to form the drop panel219and the slab structure500in connection with the column100or the wall body, with the result that the construction will be provided as shown inFIGS. 11 and 12.

The drop panel structure obtained through the process includes the plurality of reinforced concrete columns100or walls, the connecting member210having the concrete drop panel219placed on the respective floors of the column100or wall and having the cross-section area larger than that of the column100or wall, and a portion of the linear member220connected to the plurality of connecting members210or the slab structure500between the connecting members210.

Since the connecting member210includes the concrete drop panel219, the amount of sagging of the connecting member210becomes smaller than that of a portion of the linear member220or the slab structure500between the connecting members210.

Further, in the first to third embodiments, as shown inFIG. 19, the vertical mold102is fastened to the connecting member210by means of a bolt217, and, since bolt coupling is a conventional coupling manner, the detailed description thereof will be omitted.

A fourth embodiment method of constructing the drop panel structure will now be described.

FIG. 20is a flow chart illustrating a procedure of the fourth embodiment method of constructing the drop panel structure,FIG. 21is a horizontal sectional view illustrating the state in which section steel is vertically installed in the construction of the invention,FIG. 22is a horizontal sectional view illustrating the state in which the connecting members are installed in places on the respective floors of the section steel ofFIG. 21,FIG. 23is a horizontal view illustrating the state in which the linear members are connected to the connecting members ofFIG. 22, andFIG. 24is a horizontal sectional view illustrating the state in which vertical and horizontal molds are installed in the construction ofFIG. 23.

In the first step S410, a plurality of section steels400, used in the steel-framed reinforced concrete column101as shown inFIG. 11, is installed vertically as shown inFIG. 21.

In the second step S420, the connecting member210is installed on the respective floors of the section steel400as shown inFIG. 22, the connecting member210having the internal space214, the cross section of which is larger than that of the column101.

In the third step S430, the linear member220is connected to the plurality of connecting members210as shown inFIG. 23.

If needed, only the upper horizontal mold320may be installed between the connecting members210without providing the linear member220.

In the fourth step S440, the vertical mold102, shaped like a column, and the upper horizontal mold320are installed around the column and between the linear members220.

In the fifth step S450, the lower horizontal mold330is installed on the lower side of the internal space214, and reinforcing rods341are placed on the upper horizontal mold320and the lower horizontal mold330, through which step the construction obtained is provided as shown inFIG. 10, if the column100is replaced with the vertical mold102in which the section steel400is provided.

In the sixth step S460, concrete is poured into the internal space214, the vertical mold102, and the upper horizontal mold320to form the drop panel219, the column101, and the slab structure500as shown inFIG. 11.

The drop panel structure obtained through the process includes the plurality of steel-framed reinforced concrete columns101, the connecting member210having the concrete drop panel219placed on the respective floors of the column101and having the cross-section area larger than that of the column101, and a portion of the linear member220connected to the plurality of connecting members210or the slab structure500between the connecting members210.

Since the connecting member210includes the concrete drop panel219, the amount of sagging of the connecting member210becomes smaller than that of a portion of the linear member220or the slab structure500between the connecting members210owing to the existence of the drop panel219.

FIG. 25is a vertical sectional view illustrating the state in which the connecting members are connected to the section steel.

In the second step S420of the fourth embodiment, the connecting member210is connected to the section steel400by means of the coupling section218and the bolt253.

As the bolt coupling is a conventional coupling method, the detailed description thereof will be omitted.

FIG. 26is a vertical sectional view illustrating the state in which the connecting members are connected to the reinforced concrete beam of the invention, andFIGS. 27 and 28are perspective views illustrating the column and the connecting member of the invention.

The portion of the connecting member210of the drop panel structure, which is formed into a latticing form, will be hereinafter referred to as a “structural member”700or800.

The structural members700or800intersect each other at the same level in a manner as to be parallel with the respective surfaces of the column100, outside the drop panel219, to form a latticing form.

The structural member700or800is formed with a reinforced concrete beam700, in which main reinforcement steels710are coiled with the stirrup712, or a steel-framed beam800.

A connecting end702provided in the reinforced concrete beam700as shown inFIG. 27facilitates the connection between the connecting member210and the reinforced concrete structure to be connected thereto, and reinforcing the connecting strength as well.

Further, a connecting end802provided in the steel-framed beam800as shown inFIG. 28facilitates the connection between the connecting member210and the steel-framed structure to be connected thereto, and reinforcing the connecting strength as well.

The connecting member210having the connecting end702or802will now be described in more detail.

First, if the connecting member210is connected to the linear member or the slab via the connecting end702or802, the connection becomes easy and the connecting strength becomes improved owing to the shape of the connecting end702or802.

Second, if the slab is formed on the connecting member210without the connecting member210being connected to other member via the connecting end702or802, the connecting member210serves to reduce the sagging of the slab.

Here, in the case that the connecting member210is formed into a rectangular shape, which simply surrounds the drop panel219, the connecting member only reduces the sagging of the slab by the size of the rectangular area. Thus, in order to improve the effect, the drop panel, and therefore the connecting member surrounding the drop panel, have to be made larger, so that the cost of manufacturing the drop panel219and the rectangular connecting member increases.

However, since the connecting member210of the invention is formed into a latticing form so that the connecting end702or802is provided in addition to the drop panel219and the member surrounding the drop panel, the sagging of the slab is furthermore reduced by the existence of the connecting end702or802.

Thus, even though the drop panel219is not made larger, the sagging of the slab can advantageously be maximally restricted by the portion of the connecting end702or802.

Accordingly, the invention provides effects of utilizing technical benefits to the maximum in that even though the drop panel219is not made larger, the sagging of the slab can be greatly reduced while the constructing cost is saved.

FIGS. 29 and 30are perspective views illustrating the state in which a slant tension member is installed to the connecting member. InFIG. 29, the slant tension member410is installed parallel with or perpendicular to the respective surfaces of the neighboring column100as seen in a plan view so as to connect the column100and the reinforced concrete beam700to each other in an inclined state in the connecting member210. InFIG. 30, the slant tension member412is installed at an angle of 45° to the respective surface of the neighboring column100as seen in a plan view so as to connect the column100and the reinforced concrete beam700to each other in an inclined state in the connecting member210.

The slant tension member410or412serves to prevent the latticed connecting member210from sagging outwards. The slant tension member410ofFIG. 29has a benefit in installation, and the slant tension member412ofFIG. 30has a benefit in effective sag prevention.

FIGS. 31 and 32are perspective views illustrating the connecting member whose sectional area is enlarged.

InFIG. 31, a connecting end600of the reinforced concrete beam700is configured such that a cross-section area of the upper portion614is larger than that of the lower portion612, so that deformation due to load applied to the connecting member210is reduced more effectively.

Further, inFIG. 32, a connecting end680of the steel-framed beam800is configured such that a cross-section area of the upper portion684is larger than that of the lower portion682, so that deformation due to load applied to the connecting member210is reduced more effectively.

Although preferred embodiments of the present invention have been described for illustrative purposes, those skilled in the art will appreciate that the present invention is not limited thereto, but various modifications, additions and substitutions are possible without departing from the scope and spirit of the invention as disclosed in the accompanying claims.