Our Ref: 68121nno P/00/009 Regulation 3.2 AUSTRALIA Patents Act 1990 INNOVATION SPECIFICATION FOR AN INVENTION ENTITLED Invention title: Precast Rebar Concrete Structure Name of Applicant: Mohammed Omar A Jazzar Address for Service A.P.T. Patent and Trade Mark Attorneys PO Box 833 Blackwood, S.A. 5051 The invention is described in the following statement: 1 PRECAST REBAR CONCRETE STRUCTURE BACKGROUND OF THE INVENTION 1. Technical Field 5 The present application relates to a construction art, more particularly, to a precast rebar concrete structure. 2. Description of Related Art Precast concrete is a specialist manufacturer of a full range of concrete products, including architectural and structural precast concrete, glass fibre 10 reinforced concrete (GRC) and street and landscape furniture. Precast concrete has been applied since the middle of the twentieth century. However, precast concrete is of limited success due mainly to precast's inflexibility in application. It has numerous limitations and lots of constrains in design, such as high cost of specialized forms for various part of the structure, the 15 need to add structural steel bars therein, and the need for large expensive lifting equipment. In the state of the art of precast concrete as shown for example in the DE2251613A1, the distribution of moments depends on the rigidity and non-flexibility of the joints between the walls and the floorslabs maintained at right 20 angles. This alleviates the slab moments which often are excessive over the time; the redistribution of the moments permits the use of thinner floorslabs. However this redistribution has its limits, especially in high rises the distribution of moments from the slabs to walls and columns amounts to tremendous cumulative axial loads on them which results in the need of thicker walls and columns. The same applies 25 to large open space slabs, for example in malls or official buildings where a large open space is adjacent to a smaller one and therefore causing severe axial loads and moments to the supporting structure. Such building structures are disclosed in the 2 US3,748,805, US5,809,712 or W02005007986 Al. There are many other limitations concerning the usage of precast concrete, such as only one-way loading (to the two opposite supporting walls or beams, i.e. in a hollow core pre-stressed precast) and the inability to get a rigid continuous 5 floorslab or a smooth ceiling surface or one that could extend rigidly and continuously, in both horizontal directions. Thus an "off the shelf panel was needed which fits almost anywhere and is designed for this kind of loading, a panel where the structure can be built an the wiring done later on without any disturbances of the panel or any adjacent panels, one where large openings on one 10 side or even an open space garage or mall with standard panel size would be constructed with high speed and ease. US1,516,074 shows a reinforced concrete building construction. A column is integrally casted with a capital having four sides with a stepped rim. Within the recesses reinforcing elements in form of steel bars are provided. In this previously disclosed construction load on the floor is 15 transmitted via T-girders to the columns only by bearing forces. It is not possible to transmit bending moments of a noteworthy degree. This created the challenge to evolve a new precast building system that eliminates these handicaps giving the designer all the flexibility at low cost by using columns instead of walls and standardizing panel sizes. Previous precast 20 systems were heavier in weight thus the inability to use them in high rise building due to enormous cumulative weights and larger cranes required for erection SUMMARY OF THE INVENTION In view of resolving the aforementioned problems and need, it is therefore an objective of this present invention to provide a precast rebar concrete structure, 25 especially a precast concrete floorslab, for easily connecting to a concrete column. The precast rebar concrete structure has a thinner thickness than any other prior arts and is provided with a higher shearing strength and better homogeneously bending 3 strength. The proposed precast rebar concrete structure comprises a precast rebar concrete floorslab (100). The precast rebar concrete floorslab (100) comprises an upper unit (110), a lower unit (120), a plurality of first rebars (130), a plurality of 5 second rebars (140), a plurality of third rebars (150) and a plurality of fourth rebars (160). The precast rebar concrete floorslab (100) is substantially rectangularly shaped. The lower unit (120) directly connects to the bottom of the upper unit. The upper unit (110) extends out horizontally from its periphery to a shoulder portion (111). The upper unit (110) comprises a first solid portion (112). 10 The lower unit (120) comprises a plurality of light weight structures (121). The light weight structures (121) are arrayed horizontally. The periphery of the light weight structures (121) is provided a second solid portion (122). The first solid portion (112) and the second solid portion (122) are made of precast concrete and have a higher specific gravity than those of the light weight structures (121). The 15 first rebars (130) parallel and horizontally stretch out from two opposite sides of the upper unit (110) for a first predetermined length (135). The second rebars (140) parallel and horizontally stretch out from other two opposite sides of the upper unit (110) for a second predetermined length (145). The third rebars (150) parallel and horizontally stretch out from two opposite sides of the lower unit (120) for a 20 third predetermined length (155). The fourth rebars (160) parallel and horizontally stretch out from two opposite sides of the lower unit (120) for q fourth predetermined length (165). Each of the first, the second, third and the fourth predetermined lengths (135, 145, 155, 165) is greater than the thickness of the precast rebar concrete floorslab (100). 25 Meanwhile, the first rebars (130) are disposed orthogonally to the second rebars. The third rebars (150) are disposed orthogonally to the fourth rebars (160). The first, the second, the third and the fourth rebars (130, 140, 150, 160) are 4 disposed sequentially from high to low along the vertical direction. It is a further objective of the present application to provide a precast rebar concrete structure comprising a connecting pallet (200) and at least two abovementioned precast rebar concrete floorslabs (100). The connecting pallet 5 (200) is also substantially rectangularly shaped. The two precast rebar concrete floorslabs (100) connect to any two sides of said connecting pallet (200) respectively. The connecting pallet (200) stretches out a bolster portion (230) from the periphery of its lower part. The bolster portion (230) is provided to support the corresponding shoulder portion (111) of the precast rebar concrete 10 floorslab (100). The connecting pallet (200) further comprises plurality of parallel and horizontal fifth rebars (210) and a plurality of parallel and horizontal sixth rebars (220). The fifth and the sixth rebars (210, 220) are disposed orthogonally to each other. The fifth and the sixth rebars (210, 220) stretch out from the connecting pallet (200) and stretch into the neighboring precast rebar concrete 15 floorslabs (100). The fifth rebars (210) are higher than the first rebars (130) of the precast rebar concrete floorslabs (100), while the sixth rebar (220) are lower than the fourth rebars (160). Therefore, the bonding strength of the connecting pallet (200) and the precast rebar concrete floorslabs (100) are secured more than the prior arts. 20 The precast rebar concrete structures proposed in the present invention are provided with thinner thicknesses wherein the moments and loads are distributed measurely and uniformly so that the supporting structures as walls and columns are loaded in a basically uniform way. BRIEF DESCRIPTION OF THE DRAWINGS AND SYMBOLS 25 Fig. 1 shows a perspective drawing according to the first preferred embodiment of the present application. Fig. 2 shows a cross section drawing according to the first preferred 5 embodiment of the present application. Fig. 3 shows another perspective drawing according to the first preferred embodiment of the present application. Fig. 4 shows a cross section drawing according to the second preferred 5 embodiment of the present application. Fig. 5 shows a schematic drawing of the concrete column used in the precast rebar concrete structure according to the second preferred embodiment of the present application. Fig. 6 shows another schematic drawing of the concrete column used in the 10 precast rebar concrete structure according to the second preferred embodiment of the present application. Fig. 7 shows a schematic drawing of the precast rebar concrete structure according to the present application. precast rebar concrete floorslab (100) 15 upper unit (110) lower unit (120) first rebar (130) second rebar (140) third rebar (150) 20 fourth rebar (160) first predetermined length (135) second predetermined length (145) third predetermined length (155) fourth predetermined length (165) 25 shoulder portion (111) first solid portion (112) light weight structure (121) 6 second solid portion (122) sunk portion (113) steel mesh (170) connecting pallet (200) 5 bolster portion (230) fifth rebar (210) sixth rebar (220) concrete column (300) DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 10 While the present application discloses an improvement of precast rebar concrete structures, some of the implemented technologies are well known in the art and need not be discussed at length herein. In addition, the accompanying drawings and dimensions disclosed herewith are only for illustrating features provided in the present invention without limiting the patent rights. 15 Please refer to Fig. 1, which showing a perspective drawing according to the first preferred embodiment of the present invention, a precast rebar concrete floorslab (100) is provided. The precast rebar concrete floorslab (100) comprises an upper unit (110), a lower unit (120), a plurality of first rebars (130), a plurality of second rebars (140), a plurality of third rebars (150), and a plurality of fourth rebars 20 (160). The first rebars (130) are horizontally and parallel disposed. The second rebars (140) are horizontally and parallel disposed. The third rebars (150) are horizontally and parallel disposed. The fourth rebars (160) are also horizontally and parallel disposed. The lower unit (120) directly connects to the bottom of the upper unit (110). 25 The upper unit (110) is bigger than the lower unit (120), because the upper unit (110) extends out horizontally from its periphery to a shoulder portion (111). The shoulder portion (111) is provided for match the connecting pallet (200) as shown 7 in Fig. 4. Please refer to Fig. 2. The upper unit (110) has a first solid portion (112). The lower unit (120) comprises a plurality of light weight structures (121), which being arrayed horizontally. A second solid portion (122) is provided at the periphery of 5 the light weight structures (121). Since the light weight structures (121) are arrayed and spaced without contacting to each other, the second solid portion (122) is therefore lattice-like. The first and the second solid portions (112, 122) are made of precast concrete, while the light weight structure (121) is made of a light-weight material rather than the concrete. Any kind of the light-weight materials used, such 10 as plastics, expandable polystyrene, waffles, or woods, must have a less specific gravity than that of precast concrete. The light weight structure (121) is not for the purpose of material stealing or short-changing. It is applied via the principles of structural mechanics to lighten the weight while maintaining the sufficient bending strength. The concept of using the light weight structure (121) in the lower unit 15 (120) is similar to the I beam, the U beam or the H beam, which being well proved and widely applied. Please refer to Fig. 1. The first rebars (130) stretch out for a first predetermined length (135) from two opposite sides of the upper unit (110), while the second rebars (140) stretch out for a second predetermined length (135) from 20 the other two opposite sides of the upper unit (110). The third rebars (150) stretch out for a third predetermined length (135) from two opposite sides of the lower unit (120), while the fourth rebars (160) stretch out for a fourth predetermined length (135) from the other two opposite sides of the lower unit (120). The first, the second, the third and the fourth rebars (130, 140, 150 160) together form a 25 backbone of the precast rebar concrete floorslab (100). Without these rebars (130, 140, 150, 160), the concrete floorslab will be easily crashed. Another key issue of preferred embodiment is that each of the first, the second, 8 the third and the four predetermined lengths (135, 145, 155, 165) must be greater than the thickness of the precast rebar concrete floorslab (100). When the precast rebar concrete floorslabs (100) are applied practically, they will be bonded to the connecting pallets (200), as shown in Fig. 4, to form a construction building. 5 These first, the second, the third and the fourth predetermined lengths (135, 145, 155, 165) must stretch into the connecting pallet (200), so as to get enough bonding strength. The more length stretching into the connecting pallet (200), the more bonding strength achieved. It is similar to the piling for the foundations. The deeper of the piling, the higher of the foundation. The experiments show that, 10 when each of these predetermined lengths (135, 145, 155, 165) is greater than the thickness of the precast rebar concrete floorslab (100), the precast rebar concrete floorslab (100) and the connecting pallet (200) will be bonded as a rigid body to have sufficient strength. In this preferred embodiment, the first rebars (130) and the second rebars (140) 15 are disposed orthogonally to each other in the upper unit (110), while third rebars (150) and the fourth rebars (160) are disposed orthogonally to each other in the lower unit (120). For improving the shearing strength, the vertical positions of these rebars (130, 140, 150, 160) are disposed at different vertical positions. For example, their vertical positions from high to low are suggested to be the first 20 rebars (130), the second rebars (140), the third rebars (150), and the fourth rebars (160) sequentially. Such disposition of rebars (130, 140, 150, 160) will result in a better shearing strength and bending strength of the precast rebar concrete floorslab (100). Please refer to Fig. 3. The upper unit (110) near its center area is further 25 provided with a sunk portion (113). The first solid portion (112) is peripherally provided around the sunk portion (113). In this preferred embodiment, the first and the second rebars (130, 140) stretch in both the first solid portion (112) and the 9 sunk portion (113) of the upper unit (110) as shown in Fig. 2. Please refer to Fig. 2. The precast rebar concrete floorslab (100) further comprises a steel mesh (170), which being disposed above the first rebars (130) in the sunk portion (113). The steel mesh (170) is suggested to have a wire diameter 5 less than any diameter of the first rebars (130) and the second rebars (140). When the steel mesh (170) is disposed above the first rebars (130), the sunk portion (113) is then filled with fresh concrete, which being formed later than the precast concrete of the first solid portion (112) of the upper unit (110). In the practical construction process, the fresh concrete is not filled in sunk portion (113) until the 10 precast rebar concrete floorslab (100) has been moved to the construction field and ready for being bonded with the connecting pallet (200). Whereby, the weight of the precast rebar concrete floorslab (100) is decreased before the construction, so as to reduced the energy consumption for transporting the precast rebar concrete floorslab (100). 15 In this embodiment, the light weight structures (121) in the lower unit (120) are provided for reducing the weight of the precast rebar concrete floorslab (100). For easier manufacturing, the light weight structure (121) might be a cylindrical bar preferably with a rectangular cross section or a round cross section. At the meantime, the light weight structure (121) doesn't resist to the shearing force and 20 the bending moment actually, so the third and the fourth rebars (150, 160) are suggested to be disposed only in the second solid portion (122) rather than in the light weight structure(121). Based on the inventive concept disclosed in the first preferred embodiment, the present invention further provides a second preferred embodiment, which being 25 another precast rebar concrete structure as shown in Fig. 4. The precast rebar concrete structure shown in Fig. 4 comprises a connecting pallet (200) and at least two precast rebar concrete floorslabs (100) as provided in 10 the first preferred embodiment. The connecting pallet (200) is roughly rectangularly shaped. At least two sides of the connecting pallet (200) are bonded with precast rebar concrete floorslabs (100), in which, each side of the connecting pallet (200) is bonded with a precast rebar concrete floorslab (100) respectively. 5 The connecting pallet (200) comprises a bolster portion (230) which stretching out from the periphery of the lower part of the connecting pallet (200). The bolster portion (230) is provided to support the shoulder portion (111) of the precast rebar concrete floorslab (100) which being bonded to the connecting pallet (200). Please refer to Fig. 5. The connecting pallet (200) further comprises a plurality 10 of fifth rebars (210) and a plurality of sixth rebars (220) parallel and horizontal provided therein. The fifth and the sixth rebars (210, 220), which being disposed orthogonally to each other, stretch out from the connecting pallet (200) and stretch into the neighboring and bonded precast rebar concrete floorslabs (100). The bonding force of the connecting pallet (200) and the precast rebar concrete 15 floorslabs (100) is therefore secured. In this preferred embodiment, as shown in Fig. 4, the vertical position of the fifth rebars (210) is preferably higher than the vertical position of the first rebars (130) of the precast rebar concrete floorslab (100); while the vertical position of the sixth rebars (220) is preferably lower than the vertical position of the fourth rebars 20 (160) of the precast rebar concrete floorslab (100). The shearing strength and bending force of the connecting pallet (200) and the precast rebar concrete floorslabs (100) is therefore enhanced. Please refer to Fig. 5 and Fig. 6. The precast rebar concrete structure further comprises a concrete column (300) for supporting and securing the connecting 25 pallet (200). The connecting pallet (200) would be disposed on the upper part of the concrete column (300) as shown in Fig. 5; or disposed on the lower part of the concrete column (300) as shown in Fig. 6. 11 Please refer to Fig. 7, which being the architecture built by the precast rebar concrete structures proposed by the present invention. The precast rebar concrete floorslabs (100), connecting pallets (200) and concrete columns (300) are all made previously. For building the architecture, the precast rebar concrete floorslabs (100), 5 connecting pallets (200) and concrete columns (300) are transported individually to the constructing field. When assembled to each other, the fresh concrete is then applied for finally bonding and securing them all. The construction is faster than the prior art so as to save time and money. The precast rebar concrete floorslab (100) and the connecting pallet (200) proposed by the present invention are thinner, 10 but provided with higher shearing strength and bending strength. The stress in the precast rebar concrete floorslab (100) and the connecting pallet (200) is more uniform. Theses benefits get lots of contribution to building construction. Although the particular embodiments of the invention have been described in detail for purposes of illustration, it will be understood by one of ordinary skill in 15 the art that numerous variations will be possible to the disclosed embodiments without going outside the scope of the invention as disclosed in the claims and the equivalents. 12