[DESCRIPTION] [Invention Title]

STRUCTURE HAVING REINFORCEMENT OF THREE-DIMENSIONAL TRUSS TYPE CELLULAR MATERIAL AND MANUFACTURING METHOD THEREOF

[Technical Field]

The present invention relates to structures having reinforcement of three-dimensional truss type cellular materials and methods for manufacturing the same, and more particularly, to structures of concrete, loess, gypsum or the like, which use three-dimensional truss type cellular materials as reinforcement, and a manufacturing method of the same.

[Background Art] Generally, steel reinforcement is used to form reinforcements in construct ion or civi 1 engineering. To define exterior forms of wal Is and other structures, formwork is positioned around the reinforcements, and concrete or mortar is filled and cured, after which the formwork is removed to yield a wall or other structure. Thus, strong walls can be obtained through the use of steel reinforcements that strengthen the supporting capacity of the cured concrete or mortar.

Such steel reinforcements can be categorized into reinforcing bars, round steel bars, and deformed steel bars, which are specified in KSCKorean Standard) D3504 (Steel bars for concrete reinforcement) in terms of type, dimensions, materials, etc.

In addition, because inorganic materials such as concrete, mortar and loess are inexpensive and have high workability, they are widely used in the fields of construction and civil engineering.

However, such inorganic materials are characteristically brittle, and are subject to shrinkage deformation during drying or hardening that can cause cracking of a structure. Accordingly, the use of inorganic materials as parts supporting the tensile or bending stresse in structures is limited. To solve those problems, methods of arranging wire meshes and adding various fibers during mixing as sub materials have recently been widely used.

The method of arranging wire mesh requires a process of weaving wire mesh at uniform intervals in order to maximize the reinforcement. However, on-site workability requirements favor a thin-gauge wire mesh, which cannot be used when high strength is required.

Furthermore, in the case of the method of adding various fibers in the mixing step, thin fibers of several mm or less are mixed or combined. As such fibers, various materials can be used, for example, natural fibers such as bamboo or yam, and modern high-strength fibers such as glass fiber, carbon fiber and synthetic resin fiber. For example, in the case of chopped fibers, there is a method of mixing them disorderly. In the case of long fibers, there is a method of arranging them in one direction, or a method of laminating the fibers, which are arranged in one direction, in several directions. Also, there is a method of combining woven form such as texture with inorganic materials.

In particular, in order to increase the strength of concrete and eliminate several disadvantages, materials composed of mixed/compounded fibers are called Fiber Reinforced Concrete (FRC), and the FRC has been actively studied and used as special concrete. [Recent concrete engineering, Korea concrete institution, Kimoondang, ISBN, 89-7086-091-693540, Seoul]

Examples of such special concrete include Steel Fiber Reinforced Concrete (SFRC), Glass fiber Reinforced Concrete (GRC), and Carbon Fiber Reinforced Concrete (CFRC).

The arrangement of the long fibers in one direction, the stacked arrangement of the long fibers arranged in one direction, or the arrangement of the woven fibers such as texture is advantageous in view of strength, but disadvantageous in view of workability. In addition, in the case where the chopped fibers are mixed disorderly, workability is excellent, but strength is low. Also, it is technical Iy difficult to uniformly distribute the fibers in inorganic matrices whose physical properties are different from those of the fibers.

In other words, the thin chopped fibers have disadvantages in that they are easily pulled out and separated from the concrete which is a matrix, and their strength is greatly reduced when mixing with aggregate of large grain size such as gravels. Furthermore, the glass fibers have disadvantages in that they are weak against chemical corrosion caused by the strong alkaline matrix. The steel fibers have disadvantages in that the attachment strength with the matrix is low.

Meanwhi Ie, studies have recently been actively conducted on open cell light structures having truss structures. Because such open cell light structures have the truss structures designed to have optimal strength and stiffness through precise mathematical/mechanical computations, they have excellent mechanical properties.

Regarding such truss structures, it is known that a pyramid truss, an Octet truss [R. Buckminster FuI ler , 1961, U.S. patent No.2,986,241], and a Kagome truss [S. Hyun, A.M. Karlsson, S. Torquato, A.G. Evans, 2003, Int J. of Solids and structures, Vol. 40, pp. 6989-6998] are superior in a strength-to- weight ratio. FIGS. 1 through 3 are

perspective views illustrating each single layer of the pyramid truss 11, the Octet truss 12, and the Kagome truss 13 according to the related art.

Meanwhile, several practical methods for manufacturing truss type cellular materials are known.

First, wire meshes are woven by two-directional wires perpendicular to each other, and the wire meshes are laminated and bonded. Then, the resulting structure is expanded in the laminated direction to form a truss. [D.J. Sypeck and H.G.N. Wadley, 2001, J. mater, Res. Vol. 16, pp. 890-897]

As an example, FIG. 4 illustrates the shape of the cellular material manufactured by the above-described method. That is, FIG. 4 illustrates the conventional truss type cellular material 21 which is manufactured by laminating and bonding the wire meshes and expanding them in the laminated direction. However, it is known that the strength of the truss is somewhat inferior to the three types of the trusses of FIGS. 1 through 3.

Second, the pyramid truss is manufactured by folding an expanded metal or a plain-woven wire meshes along diagonal lines into a triangular wave shape. [F.W. Zok, S.A. Waltner, Z. Wei, H.J. Rathbyn,

R.M. McMeeking, A.G. Evans, 2004, International J. of Solid and

Structure, VoI 41, pp. 6249-6271]

As an example, FIG. 5 is a perspective view illustrating the conventional pyramid truss manufactured by folding the expanded metal or plain-woven wire meshes into a triangular wave shape. The pyramid truss 32 is manufactured by folding an expanded metal or plain-woven wire mesh 31 along diagonal lines in a convex and concave shape like triangular waves.

Third, the structure similar to the Kagome truss is manufactured by modifying the existing expanded metal manufacturing process. [Yoon, Chi-sang, Jung, Jae-gyu, Kang, Ki-ju, Lim, Chae-hong, Park, Moon-soo, Korean Patent Publication No. 10-0706375] As an example, FIG. 6 illustrates the conventional cellular material 41 manufactured to have the structure similar to the Kagome truss by modifying the method of manufacturing the expanded metal. Fourth, the Octet and Kagome truss structures are manufactured using metal lie wires as raw materials, based on tri-axial weaving. [J.H. Lim and K.J. Kang, 2006, International J. of Solid and Structure, Vol. 43, pp. 5228-5246]

As an example, FIG. 7 illustrates the conventional Octet truss 51 manufactured using wires as raw materials, based on tri-axial weaving. A reference symbol A represents a cross-up view of the vertix at which three wires crossly pass to each other. Also, FIG. 8 is a perspective view illustrating the conventional Kagome truss structure manufactured using wires as raw materials, based on tri-axial weaving.

Reference symbols B and C represent cross-up views of the vertices at which three wires crossly pass to each other. According to the above-described methods, in order to the multi-layer truss type cellular materials, several single-layer truss structures are laminated such that the vertices of their upper and lower layers come in contact with one another and then are bonded together, so that too much bonded joints exist. Thus, it is disadvantageous in respects of bonding cost and strength.

[Disclosure] [Technical Problem]

The present invention provides structures having reinforcement of three-dimensional truss type cellular materials, which are capable of greatly improving mechanical properties such as strength or toughness of construction and civil engineering structures because the cellular materials have the morphology regularly repeating structures similar to the ideal truss and the open cell architecture, and methods for manufacturing the same.

The present invention also provides structures having reinforcement of three-dimensional truss type cellular materials, which are capable of completely constraining the reinforcement with the matrix by filling the open inner spaces of the truss structure with the matrix and thus improving the resistance against separation, and methods for manufacturing the same.

[Technical Solution]

According to an aspect of the present invention, there is provided a structure having a reinforcement of a three-dimensional truss type cellular material, including: a matrix for a structure having a predetermined strength; and a reinforcement that is a three-dimensional truss type cellular material having a regularly repetitive pattern and an open cell architecture similar to an ideal truss, wherein the reinforcement is arranged inside the matrix in order to reinforce the matrix.

The reinforcement of the three-dimensional truss type cellular material may be one of a pyramid truss, an Octet truss, and a Kagome truss.

The pyramid truss, the Octet truss, and the Kagome truss may be formed in a single layer or laminated layers.

The matrix may be an inorganic material, and the inorganic material may be one of concrete, mortar, loess, and gypsum.

The reinforcement of the three-dimensional truss type cellular material maybe a three-dimensional truss type eel IuIar material formed by six-directional continuous wire groups having an relative angle of

60 degrees or 120 degrees to one another in a three-dimensional space.

The reinforcement of the three-dimensional truss type cellular material maybe a three-dimensional truss type cellular material formed by inter-crossing wire groups, which include parallel straight wires and are spaced apart by a predetermined distance (w), in six directions at a relative angle of 60 degrees or 120 degrees to one another in a three-dimensional space.

According to another aspect of the present invention, there is provided a method for manufacturing an inorganic structure having a reinforcement of a three-dimensional truss type cellular material , the method including: a) preparing a three-dimensional truss type cellular material as the reinforcement of the inorganic structure; b) forming a formwork which is a temporary structure for maintaining a predetermined shape and dimension of an inorganic material for a matrix and supporting the inorganic material for the matrix until the inorganic material for the matrix is cured up to an appropriate strength; c) arranging the three-dimensional truss type cellular material in the inside of the formwork; d) filling the inorganic material for the matrix into the formwork where the three-dimensional truss type cellular material is arranged, and curing the filled inorganic material for the matrix; and e) removing the formwork to complete the inorganic structure.

The inorganic material for the matrix may be one of concrete,

mortar, loess, and gypsum.

The reinforcement of the three-dimensional truss type cellular material may be one of a pyramid truss, an Octet truss, and a Kagome truss. The reinforcement of the three-dimensional truss type cellular material may be a three-dimensional truss type eel lular material formed by six-directional continuous wire groups having a relative angle of

60 degrees or 120 degrees to one another in a three-dimensional space.

The reinforcement of the three-dimensional truss type cellular material may be a three-dimensional truss type cellular material formed by intercrossing wire groups, which include parallel straight wires and are spaced apart by a predetermined distance (w), in six directions at a relative angle of 60 degrees or 120 degrees to one another in a three-dimensional space. According to another aspect of the present invention, there is provided a method for manufacturing a concrete structure having a reinforcement of a three-dimensional truss type cellular material, the method including: a) forming a three-dimensional truss type cellular material, as the reinforcement of the concrete structure, by using six-directional continuous wire groups having an azimuth angle of 60 degrees or 120 degrees in a space; b) forming a formwork which is a temporary structure for maintaining a predetermined shape and dimension of a concrete poured therein and supporting the concrete until the concrete is cured up to an appropriate strength; c) arranging the three-dimensional truss type cellular material in the inside of the formwork; d) mixing the concrete by using cement, water, aggregate, and admixture added when necessary! e) pouring the mixed concrete into the forwork where the three-dimensional truss type cellular material

is arranged; and f) performing drying and curing processes to accelerate the hardening of the poured concrete.

The three-dimensional truss type cellular material in the step a) may be cut or joined according to usage and shape of the concrete structure.

[Advantageous Effects]

According to the embodiments of the present invention, since the three-dimensional truss type cellular material fabricated in advance has only to be placed inside the formwork before pouring the concrete mixture, it is possible to save time and manpower necessary to form, install and fix the steel reinforcement.

In addition, since the reinforcement is uniformly arranged inside the concrete without the complex fiber mixer necessary in the process of manufacturing the fiber reinforced concrete structure, local defects or strength non-uniformity can be minimized. At this point, the three-dimensional truss type cellular material used as the reinforcement has the optimal strength-to-weight ratio in itself.

Thus, when combined with the concrete, the three-dimensional truss type cellular material has the greatest strength increase, compared with the existing lattice-type steel reinforcement structure or wire meshes, or the randomly arranged fibers.

Furthermore, since the reinforcement of the present invention is continuously connected in the truss structure, the number of cut sections in the reinforcement is fewer than in a reinforcement using chopped fibers or in a discontinuous reinforcement, therefore the resistance to the separation of the reinforcement from the concrete matrix is high because the reinforcement and the matrix completely

constrain each other.

Moreover, when the reinforcement of the truss type cellular material is made of metal, the heat transfer is so excellent that heat generated by the hydration reaction in the concrete curing process can be easily dissipated, thereby suppressing the occurrence of crack and reducing the solidification time.

[Description of Drawings]

FIGS. 1 through 3 are perspective views illustrating a single layer of a pyramid truss, an Octet truss, and a Kagome truss according to the related art.

FIG. 4 is a perspective view illustrating a conventional truss type eel lular mater ial manufactured by laminating and bonding the wire meshes and stretching them in the laminated direction. FIG.5 is a perspective view illustrating a conventional pyramid truss manufactured by folding the expanded metal or plain-woven wire mesh into a triangular wave shape.

FIG.6 is a perspective view illustrating a conventional cellular material manufactured to have the structure similar to a Kagome truss by modifying the conventional method of manufacturing an expanded metal.

FIGS.7 and 8 are perspective views illustrating a conventional Octet truss structure and a conventional Kagome truss structure manufactured using wires as raw materials, based on tri-axial weaving. FIG.9 is a view illustrating a structure having a reinforcement of a three-dimensional truss type cellular material according to an embodiment of the present invention.

FIG. 10 is a view illustrating the reinforcement of the

three-dimensional truss type cellular material of FIG. 9.

FIG. 11 is a perspective view illustrating a unit cell of the reinforcement of the three-dimensional truss type cellular material of FIG. 9. FIG.12 is a view illustrating a structure having a reinforcement of a three-dimensional truss type cellular material according to another embodiment of the present invention.

FIG. 13 is a view illustrating the reinforcement of the three-dimensional truss type cellular material of FIG. 12. FIG. 14 is an operation flowchart illustrating a method for manufacturing an inorganic structure having a reinforcement of a three-dimensional truss type cellular material according to an embodiment of the present invention.

FIG. 15 is an operation flowchart illustrating a method for manufacturing a concrete structure having a reinforcement of a three-dimensional truss type cellular material according to an embodiment of the present invention.

FIG. 16 is an operation flowchart illustrating a method for manufacturing a reinforcement of a three-dimensional truss type eel lular material according to an embodiment of the present invention.

[Best Mode]

Hereinafter, structures having three-dimensional truss reinforcements and methods for manufacturing the same according to embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In recent years, there were proposed three-dimensional cellular ultra-1 ight structures simi lar to an ideal Kagome truss, which is woven

or assembled by intercross six-directional continuous wire groups having a relative angle of 60 degrees or 120 degrees to one another in a three-dimensional space, and methods for manufacturing the same. (Kang, Ki-ju, Lee, Yong-hyun, Korean Patent Registration No. 10-0708483) (Kang, Ki-ju, Lee, Yong-hyun, Korean Patent Application No. 10-2006-0119233). According to those methods, wires are intercrossed together so that their shapes are maintained, even without bonding the intersections of the wires after wire assembling.

As a similar method, there is a method for manufacturing a three-dimensional cellular structure, which is manufactured by arranging straight wires in six directions without bending, and then bonding intersections. (Kang, Ki-ju, Kim, Nam-hyun, Korean Patent

Registration No. 10-0566729)

The ultra-light structure generally refers to a metal structure having a very high porosity. Unlike fiber reinforced plastics (FRP) or polymer lightweight material , the ultra-light structure can be used at high temperature environment of several hundred and is superior in strength and impact absorption capacity. The ultra-light structure has excellent physical and mechanical performances, such as low density, heat resistance, high strength, ability to absorb impact and noise, and high-efficiency cooling, and also its inner space can be used for liquid storage and wiring.

The above documents are hereby incorporated by reference.

An embodiment of the present invention provides a structure and a method for manufacturing the same, in which three-dimensional truss type eel lular mater ial structure is arranged as reinforcement in order to increase strength and suppress cracks and shrinkage in the structures of inorganic materials such as concrete, mortar, loess and

gypsum.

In the embodiment for solving the problems of steel reinforcement , wire meshes or various fibers used for reinforcing the concrete, the cellular materials having the three-dimensional truss structure are arranged in concrete, loess or gypsum. In this way, high-strength concrete structures which are superior in strength and other physical properties can be manufactured at low cost. In this case, the cellular materials may be metal or nonmetal.

FIG. 9 illustrates a structure having a reinforcement of a three-dimensional truss type cellular material according to an embodiment of the present invention.

Referring to FIG.9, the structure 100 having the reinforcement of the three-dimensional truss type cellular material according to the embodiment of the present invention includes a matrix 120 and a reinforcement 110 of a three-dimensional truss type cellular material .

The matrix 120 is an inorganic material for a structure having a predetermined strength, and may be one of concrete, mortar, loess, and gypsum.

The reinforcement 110 of the three-dimensional truss type cellular material is a three-dimensional cellular ultra-light truss having a regularly repetitive morphology and an open cell architecture similar to the ideal truss, and may be placed inside the matrix to reinforce the matrix. The reinforcement 110 of the three-dimensional truss type cellular material according to the embodiment of the present invention represents the three-dimensional truss type cellular material having a structure similar to an ideal Kagome truss woven or assembled by intercrossing six-directional continuous wire groups having an relative angle of 60 degrees or 120 degrees to one another

in a three-dimensional space.

In addition, the reinforcement 110 of the three-dimensional truss type eel lular material according to the embodiment of the present invention may be one of a pyramid truss, an Octet truss, and a Kagome truss. The pyramid truss, the Octet truss, and the Kagome truss may be formed in a single layer or in laminated layers.

FIG. 10 illustrates the reinforcement of the three-dimensional truss type cellular material of FIG. 9.

Referring to FIG.10, the reinforcement of the three-dimensional truss type cellular material of FIG.9 is formed by assembling the first to sixth-axial wires in three-dimension. Each of the first to sixth-axial wires are formed in a spiral shape in advance before assembling. The spiral first to third-axial wires are assembled to form a plurality of two-dimensional Kagome planes, and the spiral 4-axial to 6-axial wires are assembled in out-of-plane directions with the first to third-axial wires of the two-dimensional Kagome planes.

In this case, wherein the first, second and third-axial wires are assembled to form the two-dimensional Kagome planes comprising A, B and C layers in sequence from the bottom, and the wires in one layer are arranged to be constantly shifted from the wires on adjacent layers so as to maintain position deviations in horizontal and vertical directions with respect to adjacent layers.

More specifically, the unit cell of the reinforcement of the three-dimensional truss type cellular material of FIG. 9 will be described below.

FIG. 11 is a perspective view illustrating the unit cell of the reinforcement of the three-dimensional truss type cellular material of FIG. 9.

Referring to FIG. 11 in the unit cell of the reinforcement of the three-dimensional truss type cellular material, three wires are intersected at 60 degrees or 120 degrees to each other at their intersections. Such a structure includes six-directional wire groups 114, 115, 116, 117, 118 and 119 arranged to have the specif ic directions in the three-dimensional space.

The unit cell formed by the six-directional wire groups 114, 115, 116, 117, 118 and 119 is configured such that two regular tetrahedrons forming analogous shapes are symmetrically faced at one apex. The structure of the unit cell will be described below.

The wire groups 114, 115 and 116 are intercrossed on the same plane (X-Y plane) to form a regular triangle. The wire 7 is intercrossed at the intersection of the wires 5 and 6; the wire 8 is intercrossed at the intersection of the wires 4 and 5; and the wire 9 is intercrossed at the intersection of the wires 6 and 4. In this case, the wire groups 116, 119 and 117 is intercrossed to form a regular triangle; the wire groups 114, 118 and 119 is intercrossed to form a regular triangle; and the wire groups 115, 117 and 118 are intercrossed to form a regular triangle. Accordingly, the six-directional wire groups 114, 115, 116, 117, 118 and 119 form one regular tetrahedron (first regular tetrahedron).

The wires disposed above the apex (reference apex) of the first regular tetrahedron formed by the intercrossing of the wire groups 117,

118 and 119 over the X-Y plane and selected from other groups 114', 115' and 116 having the same direction as the wire groups 114, 115 and

116 are arranged such that they are intercrossed with two wires selected from the wire groups 117, 118 and 119 to form a regular triangle.

Accordingly, the wire groups 114' , 115' , 116' , 117, 118 and 119

form another regular tetrahedron (second tetrahedron). Consequently, the unit cell of the three-dimensional truss type cellular material 110 is formed such that the regular tetrahedron (first regular tetrahedron) formed by the wire groups 114, 115, 116, 117, 118 and 119 around the intersection formed by the wire groups 117, 118 and 119 faces the regular tetrahedron (second regular tetrahedron) formed by the wire groups 114', 115', 116', 117, 118 and 119 around the intersection formed by the wire groups 117, 118 and 119.

In order to form a plural ity of unit eel Is 110 in each direction of three-dimension, the wires are arranged such that regular tetrahedrons are formed to face each other at the other apexes of the regular tetrahedron formed by the wire groups 114, 115, 116, 117, 118 and 119 in the same manner. In this way, it is possible to the truss type cellular material having the unit cells repetitively assembled in the three-dimensional space.

At this point, the wires may be one of metal , ceramic, synthetic resin, and fiber reinforced synthetic resin, and the intersections of the wires maybe bonded by one of liquid or spray type adhesive, brazing, soldering, and welding. Meanwhile, FIG. 12 illustrates a structure having a reinforcement of a three-dimensional truss type cellular material according to another embodiment of the present invention, and FIG. 13 illustrates the reinforcement of the three-dimensional truss type cellular material of FIG. 12. Referring to FIG.12, the structure 200 having the reinforcement of the three-dimensional truss type cellular material according to another embodiment of the present invention includes a matrix 220 and a reinforcement 210 of a three-dimensional truss type cellular

material .

Since the matrix 220 is the same as the matrix 120 of FIG. 9, its detailed description will be omitted.

The reinforcement 210 of the three-dimensional truss type cellular material may be manufactured by arranging the six-directional continuous straight wire groups having a relative angle of 60 degrees or 120 degrees to one another in the three-dimensional space and bonding their intersections, without bending the wire groups.

Referring to FIG. 13, the reinforcement 210 of the three-dimensional truss type cellular material according to another embodiment of the present invention is a three-dimensional truss type cellular material formed by inter-crossing the wire groups, which include paral IeI straight wires and are spaced apart by a predetermined distance w, in six directions at a relative angle of 60 degrees or 120 degrees to one another in the three-dimensional space. In the space expressed by χ-axis and z-axis, which are perpendicular each other and existing on an identical plane, andbyy-axis perpendicular to χ-z plane, a first wire group 211 is located on the χ-z plane, and a second wire group 212 is overlapped directly on the first wire group 211 and inclined at 60 degrees in a counterclockwise direction from the first wire group 211. A third wire group 213 is overlapped on the second wire group 212 at the intersection of the first wire group 211 and the second wire group 212 and inclined at 60 degrees in a counterclockwise direction from the second wire group 212. Thus, when viewed fromy-axis, the three-directional wire groups form a lattice-shaped panel A composed of regular triangles whose one side is 2/3 ^1/2 w in length.

In addition, in the same manner as the panel A, a panel B is formed by overlapping three-directional wire groups on the plane parallel to

the χ-z plane located under by 8 ^1/2 /3w iny-axis direction from the panel A, wherein all wire intersections are displaced in parallel by 2/27 ^1/2 w in directions of two wire groups among the first wire group 211, the second wire group 212 and the third wire group 213. Furthermore, in the same manner as the panel B, a panel C is formed by overlapping three-directional wire groups on the plane parallel to the χ-z plane lower by 8 /3w in y-axis direction from the panel B, wherein all wire intersections are additionally displaced in parallel from the panel B by a distance displaced from the panel A to the panel B.

Moreover, under the panel C, the panels formed by the overlapping of three-directional wire groups are repeated in a shape of the panel

A, the panel B and the panel C, so that the panels are vertically located in order of panels A, B, C, A, B, C, A, ... , spaced apart by an interval of 8 ^1/2 /3w in y-axis direction.

In addition, the individual wires of the fourth wire group 214 contact the intersections of the three-directional wires on one of the panels A, B and C and the intersections closest among the intersections of the three-directional wires of the panel located directly on/under the panels A, B and C, and are inclined while passing through the panel.

Furthermore, the individual wires of the fifth wire group 215 and the sixth wire group 216 contact the intersections of the four-directional wire groups 211, 212, 213 and 214 and are inclined at 60 degrees or 120 degrees from the existing four-directional wires while passing through the panel. Thus, the adjacent six-directional wires are arranged at six sides of the regular tetrahedrons.

At this point, the wires may be one of metal , ceramic, synthetic resin, and fiber reinforced synthetic resin, and the intersections of

the wires may be bonded by one of liquid or spray type adhesive, brazing, soldering, and welding.

Meanwhile, FIG. 14 is an operation flowchart illustrating a method for manufacturing an inorganic structure having a reinforcement of a three-dimensional truss type cellular material according to an embodiment of the present invention.

Referring to FIG. 14, in the method for manufacturing the inorganic structure having the reinforcement of the three-dimensional truss type cellular material according to the embodiment of the present invention, three-dimensional truss type cellular material as the reinforcement of the inorganic structure is formed which includes six-directional continuous wire groups having a relative angle of 60 degrees or 120 degrees to one another in the three-dimensional space in step S1110. The three-dimensional truss type cellular material is mass-produced in advance by separate processes. In the architectural fields, if necessary, the three-dimensional truss type cellular material is cut or joined in an appropriate size and shape and then installed inside a formwork before pouring the inorganic material.

After the inorganic material is solidified, the cellular material serves to reinforce the structure. The inorganic material may be concrete, mortar, loess, or gypsum.

As described above, the reinforcement of the three-dimensional truss type cellular material may be formed by the six-directional continuous wire groups having a relative angle of 60 degrees or 120 degrees to one another in the three-dimensional space, or may be formed such that the wire groups including parallel straight wires spaced apart from each other by a predetermined distance w are inter-crossed in six directions a relative angel of 60 degrees or 120

degrees to one another in the three-dimensional space, or may be one of a pyramid truss, an Octet truss, and a Kagome truss.

Next, a formwork is formed as a temporary structure which maintains the predetermined shape and dimension and supports the inorganic material until the poured inorganic material is cured up to an appropriate strength in step S1120.

Then, the three-dimensional truss type cellular material is arranged inside the formwork in step S1130.

Thereafter, an inorganic material for matrix is filled and cured inside the formwork where the three-dimensional truss type cellular material is arranged in step S1140, and the inorganic structure is completed through a subsequent process of removing the formwork in step

S1150.

Next, a method for manufacturing a concrete structure as the inorganic structure according to an embodiment of the present invent ion will be described below.

FIG. 15 is an operation flowchart illustrating a method for manufacturing a concrete structure having a reinforcement of a three-dimensional truss type cellular material according to an embodiment of the present invention.

Referring to FIG. 15, in the method for manufacturing the concrete structure having the reinforcement of the three-dimensional truss type cellular material according to the embodiment of the present invention, three-dimensional truss type cellular material as the reinforcement of the concrete structure is formed in advanced, and wherein three-dimensional truss type cellular material includes six-directional continuous wire groups having a relative angle of 60 degrees or 120 degrees to one another in the three-dimensional space

in step S1210.

Next, a formwork is formed as a temporary structure which maintains the predetermined shape and dimension and supports the concrete until the poured concrete is cured up to an appropriate strength in step S1220.

Then, the three-dimensional truss type cellular material is arranged inside the formwork in step S1230.

Thereafter, a concrete is mixed using cement, water, aggregate, and admixture added when necessary in step S1240. Then, the mixed concrete is poured into the formwork where the three-dimensional truss the cellular material is arranged in step S1250.

Next, the drying and curing processes are performed in order to harden the poured concrete in step S1260, and the concrete structure is completed through a subsequent process of removing the formwork in step S1270.

FIG. 16 is an operation flowchart illustrating a method for manufacturing a reinforcement of a three-dimensional truss type cellular material according to an embodiment of the present invention. Referring to FIGS. 11 and 16, the method for manufacturing the reinforcement of the three-dimensional truss type cellular material according to the embodiment of the present invention is the method for manufacturing the three-dimensional truss type cellular material including six-directional continuous wire groups having a relative angle of 60 degrees or 120 degrees to one another in the three-dimensional space. Three wires 114, 115 and 116 are inter-crossed together on X-Y plane to form a basic regular triangle in step S1310.

Next, the wire 7 is intercrossed at the intersection of the wires

5 and 6; the wire 8 is intercrossed at the intersection of the wires 4 and 5; and the wire 9 is intercrossed at the intersection of the wires

6 and 4. Three wires 116, 119 and 117 are intercrossed to form a regular triangle, three wires 114, 118 and 119 are intercrossed to form a regular triangle, and three wires 115, 117 and 118 are intercrossed to form a regular triangle. Consequently, a basic regular tetrahedron (first regular tetrahedron) is formed in step S1320.

The six wires 114, 115, 116, 117, 118 and 119 are located at each edge of the regular tetrahedron, and the three wires 114', 115'and 116'having the same direction as the three wires 114, 115 and 116, respectively, are inter-crossed above the apex of the regular tetrahedron inter-crossed with the three wires 117, 118 and 119 above the X-Y plane, thereby forming another triangle in step S1330.

Next, the three wires 114' , 118 and 119, the three wires 115' , 117 and 118, and the three wires 116', 119 and 117 are intercrossed to form regular triangles, and the six wires 114', 115', 116', 117,

118 and 119 form another regular tetrahedron (second regular tetrahedron) in step S1340.

Thereafter, the unit cell is formed such that the regular tetrahedron formed by the six wires 114, 115, 116, 117, 118 and 119 around the intersection of the three wires 117, 118 and 119 faces the second regular tetrahedron formed by the six wires 114' , 115' , 116' ,

117, 118 and 119 in step S1350.

Then, the wires are arranged such that regular tetrahedrons facing one another are also formed at the other apexes formed by the six wires 114, 115, 116, 117, 118 and 119 in the same manner. The three-dimensional truss type cellular material is formed such that a plurality of unit cells can be repetitively formed in step S1360. In

this case, the first regular tetrahedron is similar to the second regular tetrahedron. If the ratio of similarity is 1:1, the structure similar to the Kagome truss is formed; and if the ratio of similarity is much greater than 1:1, the structure similar to the Octet truss is formed.

At this point, the intersections of the wires may be bonded by using one of liquid or spray type adhesive, brazing, soldering, and welding. Furthermore, the wires may be one of metal , ceramic, synthetic resin, and fiber reinforced polymer. Meanwhile, although the concrete structure having the reinforcement of the three-dimensional truss type cellular material has been described in the above embodiments, it is apparent to those skilled in the art that the present invention can also be applied when the matrix is mortar, loess or gypsum. For example, in the case of loess, water is added to loess having a predetermined size, and the loess is matured for a predetermined time. After making a formwork as a lumber frame, the three-dimensional truss type cellular material is arranged inside the formwork.

Thereafter, the matured loess is poured into the formwork and cured. In this way, the loess structure having the reinforcement of the three-dimensional truss type cellular material can be formed.

Consequently, according to the embodiments of the present invention, since the three-dimensional truss type cellular material has a structure similar to the ideal truss in itself, the strength-to-weight ratio is high and various practical manufacturing methods have been proposed. Furthermore, since the three-dimensional truss type cellular material has the open cell architecture the strength can be remarkably increased when the three-dimensional truss

type cellular material is added in the process of forming the inorganic material such as concrete, mortar, loess or gypsum.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims.