FORM 2
THE PATENT ACT, 1970
(39 of 1970)
As amended by the Patents (Amendment) Act, 2005
&
The Patents Rules, 2003
As amended by the Patents (Amendment) Rules, 2006
COMPLETE SPECIFICATION
(See section 10 and rule 13)
TITLE OF THE INVENTION
A method for 3D printing of concrete building component directly on a 3D printed concrete structure.
APPLICANTS
Aditya Birla Science and Technology Company Pvt Ltd, Plot number 1 and 1-A/1, Taloja, MIDC, Taluka- Panvel, District- Raigad- 410208, Maharashtra, India.
PREAMBLE TO THE DESCRIPTION
The following specification particularly describes this invention and the manner in which it is to be performed.

FIELD OF THE INVENTION
[001] The present invention relates to a method for 3D printing of concrete building component directly on a 3D printed concrete structure.
BACKGROUND OF THE INVENTION
[002] Conventionally, during 3D printing of concrete structures, the whole building is not constructed as a single unit. The roof is printed as a separate segment and then placed on the 3D printed walls using heavy machinery. However, this technique is time consuming and increases the cost of the construction. Additionally, while placing the 3D printed roof on the walls there is a possibility of roof breakage due to imprecise anchoring.
[003] An attempt has been made earlier to address this problem by printing slanted roofs on the printed walls however, this has also not been feasible in terms constructing a multi-storey structure or in terms of giving a flat walkable 3D printed roof.
[004] Therefore, there is a need of a method for 3D printing of concrete roof which solves the problems of the prior art.
BRIEF DESCRIPTION OF DRAWINGS
[005] Figures 1a and 1b depict perspective view of the metal wire mesh along with spikes on its edges to be placed on the walls of the concrete structure, in accordance with the embodiments of the present invention.
[006] Figure 2 depicts side view of a concrete building component 3D printed directly on a concrete structure, in accordance with the embodiments of the present invention.

SUMMARY OF THE INVENTION
[007] According to an embodiment of the present invention, there is provided a method for 3D printing of concrete building component in a different plane with respect to a 3D printed concrete structure, comprising of positioning a mesh wire on top of the 3D printed concrete structure followed by 3D printing the concrete building component on top of the mesh wire wherein the mesh wire has spikes along its edges such that the mesh wire inserts into and bonds with the free end of the 3D printed concrete structure, provided that the free end of the 3D printed concrete structure is freshly printed.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[008] The embodiments of the present invention eliminate or reduces the aforementioned problems of the prior art by providing a method for 3D printing of concrete building component directly on a 3D printed concrete structure by laying a metal wire mesh on top of the walls of the concrete structure and printing the concrete building component on top of it.
[009] According to the present invention, there is provided a method for 3D printing of concrete building component in a different plane with respect to a 3D printed concrete structure which comprises of positioning a mesh wire on top of the 3D printed concrete structure followed by 3D printing the concrete building component on top of the mesh wire. The mesh wire has spikes along its edges such that the mesh wire inserts into and bonds with the free end of the 3D printed concrete structure, provided that the free end of the 3D printed concrete structure is freshly printed.
[010] Preferably, the concrete building component such as roof bonds with the mesh wire and also on the sides with the walls of the concrete structure, ensuring a continuous bond between the roof, mesh wire and the walls of the structure. As shown in Figures 1a and 1b, the edges of the mesh

are designed such that their plane is perpendicular to the plane of the mesh wire. Therefore, upon placement of this mesh wire on the top of the freshly printed walls of the structure, the perpendicular spikes on the edges of the mesh wire pierces in the boundary of the wall of the 3D printed structure. In this way, cold joins between the roof and walls, which is found in conventional manner of printing roof separately and anchoring on the walls, can be avoided. Preferably, the metal mesh wire is designed such that the concrete component once printed, does not fall down from the perforations in the mesh wire.
[011] In an embodiment, the mesh wire is fastened to the bottom of the conventional reinforced cage or an array of metal bars, if required for the roof. This reinforcement cage and mesh wire as a combined unit is placed on the walls of the structure followed by printing of the roof on top.
[012] In an embodiment, post printing of the walls, mesh wire is placed on top of the boundary of the walls and the roof is first printed on the boundary of the structure so that stability and proper bonding at the edges is achieved first and then the remaining roof is printed.
[013] In an embodiment, the mesh wire can either be made of metal wood, polymer or any other suitable material. Also, the size of the openings/perforations of the wire mesh should be such that concrete does not fall through the mesh wire under gravity.
[014] An embodiment of the present invention as shown in Figure 2 wherein the walls of the concrete structure are printed and on top of this freshly printed structure, the metal mesh wire is placed such that it bonds with the concrete of the walls and immediately after placing the mesh wire, a building component such as a roof is printed on top of it horizontally to give a flat roof that does not fall under gravity. The roof could also form the base for additional floors above. The roof may further be smoothened to obtain a smooth surface by use of mortar and cement paste.

[015] The present method leads to an increase in speed of construction. Moreover, the integrity of the overall structure becomes better and the ease of construction also increases.
[016] The foregoing description of specific embodiments of the present invention has been presented for purposes of description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obvious modifications and variations are possible in light of the above teaching.

We Claim:
1. A method for 3D printing of concrete building component in a different plane with respect to a 3D printed concrete structure, comprising of positioning a mesh wire on top of the 3D printed concrete structure followed by 3D printing the concrete building component on top of the mesh wire wherein the mesh wire has spikes along its edges such that the mesh wire inserts into and bonds with the free end of the 3D printed concrete structure, provided that the free end of the 3D printed concrete structure is freshly printed.
2. The method as claimed in claim 1, wherein the mesh wire can be made of metal, wood, polymer or any other suitable material.
3. The method as claimed in claim 1, wherein the size of the perforations of the mesh wire are such that concrete building component being 3D printed does not fall through the mesh wire under gravity.
4. The method as claimed in claim 1, wherein the wire mesh is fastened to the bottom of a reinforced cage or an array of metal bars conventionally used for reinforcement during building construction and this combined unit is placed on the 3D printed concrete structure followed by 3D printing of the building component on top of said structure.
5. The method as claimed in claim 1, wherein the wire mesh is placed on top of the free end of the 3D printed structure and the building component is first 3D printed on the boundary of the free end of the structure so that stability and proper bonding at the boundary is achieved first and then the remaining building component is printed.