Patent Publication Number: US-2002005021-A1

Title: Pre-cast concrete panels for construction of a building

Description:
[0001] The invention relates to set of pre-cast concrete panels for construction of a building and a method of using the same in the building industry.  
       [0002] In building construction, it is often necessary to construct the structural frame work, floor slab and followed by the erection of in-fill panels (normally they are brick walls). Thereafter additional construction work has to be done in the installation of electrical wires, gas and water plumbing connections and eternal wall furnishing of the building has to be completed. All these require skilled workers and are time consuming and is expensive. The mould formwork set for pre-cast concrete industries in prior art is expensive because a specific mould only can be used for a particular project.  
       [0003] The objectives of this invention are to mitigate these disadvantages by the use of various types of pre-cast concrete panels, adoption of a universal mould formwork set and the adoption of a new system of construction of a building using the pre-cast concrete panels.  
       [0004] According to the first aspect of the invention, the pre-cast concrete wall panels comprise of:  
       [0005] 1. ‘I’ shape panels (straight line in cross-section width wise) and ‘I’ shape panels with door or window opening,  
       [0006] 2. ‘L’ shape panels and ‘L’ shape panels with door or window opening,  
       [0007] 3. ‘T’ shape panels and ‘T’ shape panels with door or window opening,  
       [0008] 4. ‘Cross’ shape cross-sectional panels and ‘Cross’ shape cross-sectional panels with door or window opening on one or more sides.  
       [0009] According to a second aspect of the invention, the pre-cast concrete wall panels, include a pre-cast concrete beam and a pre-cast concrete cornice finishing at one edge.  
       [0010] According to a third aspect of the invention, a plurality of steel links extend from the pre-cast concrete beam of the pre-cast concrete panels. An interlocking system of reinforced concrete beams if formed by the insertion of reinforcement steel bars through the links and the pouring in-situ concrete to construction joints formed by pre-cast concrete slabs and pre-cast concrete beams of the pre-cast concrete wall panels.  
       [0011] According to a fourth aspect of the invention, the length of ‘I’ shape pre-cast concrete wall panel can be adjusted at the construction stage to comply with the architectural and engineering requirements by adjusting the edge formwork of moulding formwork set. The arms of ‘L’ shape, ‘T’ shape and ‘Cross’ shape panels can also be adjusted if necessary, but normally they are constant in single size.  
       [0012] According to a fifth aspect of the invention, the pre-cast concrete slab includes recesses at the central region of the slab panel and pre-cast concrete beams along the perimeter of the slab panel.  
       [0013] According to a sixth aspect of the invention, the sizes of the pre-cast concrete slab panels can be adjusted at the casting stage to comply the architectural and structural requirements.  
       [0014] According to seventh aspect of the invention, the height of the pre-cast beam of the pre-cast concrete slab panel can be adjusted at the casting stage to comply with the structural engineering requirements.  
       [0015] Hollow cores extend longitudinally from one end to the other in the pre-cast wall and in the pre-cast slab panel. The hollow cores are designed to accommodate structural, mechanical and electrical requirement. A reinforced concrete column is formed in a bore by inserting reinforcement steel bars into the hollow core of the pre-cast concrete panel and thereafter in-filled with cast-in-situ concrete.  
       [0016] Walls can be erected and supported by introducing reinforcement steel bars and in-fill cast-in-situ concrete into the cores at both ends of the pre-cast concrete wall panels or by introducing reinforcement steel bars and in-fill cast-in-situ concrete to longitudinal recesses which form core when two pre-cast walls are placed in straight-line alignment to each other.  
       [0017] It would understood that the cores can be provided to ‘T’ shape, ‘L’ shape and ‘cross’ shape pre-cast concrete panels but cores may not be necessary to pre-cast concrete wall panels like ‘I’ shape (straight in cross section). The ‘I’ shape pre-cast concrete panel may be provided with longitudinal recesses at the both ends of the panel without any cores in between.  
       [0018] The structural linking of pre-cast concrete wall panels and pre-cast concrete slab panels is carried out by introducing reinforcement steel bars through the links extending from the pre-cast concrete beams of the wall panels, adding wire mesh and top bars to the top surface of pre-cast slab panels and pre-cast beams respectively, then pouring concrete into troughs formed by pre-cast concrete slabs and the pre-cast concrete beams to form construction joints. For single storey building, ‘U’ shape steel bars are inserted into the cast in-situ concrete columns next to each other from the two linearly aligned adjacent pre-cast concrete wall panels.  
       [0019] In-fill wall panel between comers of pre-cast concrete wall panels or between any two desired points can be obtained by using a single panel or plural number of ‘I’ shape straight wall panels placed in a linear alignment to each other. The length of any panel can be adjusted at the casting stage by sliding an adapter without altering the moulding formwork set. 
     
    
    
     [0020] The invention will be described in detail by reference to preferred embodiment and system of construction with reference to accompanying drawings in which:  
     [0021] Fig ( 1 A). Shows a top plan view, FIG. ( 1 B) shows side elevation and Fig ( 1 C) shows section cut through a core ( 6 ) of ‘I’ shape (straight line in cross section) pre-cast concrete wall panel complete with pre-cast concrete beam ( 2 ), pre-cast concrete cornice ( 4 ) finishing and steel links. ( 8 )  
     [0022] Fig ( 1 D) shows a top plan view of a ‘I’ shape pre-cast concrete wall panel without any longitudinal cores within.  
     [0023] Fig ( 2 A) &amp; ( 2 B) shows the plan and side view respectively of the ‘I’ shape panel as stated in Fig ( 1 A), ( 1 B), ( 1 C) &amp; ( 1 D) but with door opening. ( 10 )  
     [0024] Fig ( 3 A) &amp; ( 3 B) shows the plan and side view respectively of the ‘I’ shape panel as stated in Fig ( 1 A), ( 1 B), ( 1 C) and ( 1 D) but with window opening. ( 12 )  
     [0025] Fig ( 4 A) shows a top view plan, Fig ( 4 B) shows side elevation and Fig ( 4 C) shows section cut through a core of ‘L’ shape pre-cast concrete wall panel complete with pre-cast concrete beam ( 2 ) and pre-cast concrete cornice ( 4 ) finishing.  
     [0026] Fig ( 5 A) &amp; (SB) shows the plan and side view respectively of the ‘L’ shape as stated in Fig ( 4 A), ( 4 B) &amp; ( 4 C) but with door opening. ( 10 ) on an extended arm.  
     [0027] Fig ( 6 A) shows a top view plan, Fig ( 6 B) shows side elevation and Fig ( 6 C) shows section cut through a core of ‘T’ shape pre-cast concrete wall panel complete with pre-cast concrete beam ( 2 ) and pre-cast concrete cornice ( 4 ) finishing.  
     [0028] Fig ( 7 A) &amp; ( 7 B) shows the plan and side view respectively of the ‘T’ shape as stated in Fig ( 6 A), ( 6 B) &amp; ( 6 C) but with door opening ( 10 ) on an extended arm.  
     [0029] Fig ( 8 A) &amp; ( 8 B) shows the a plan and side view respectively of a ‘T’ shape as stated in Fig ( 6 A), ( 6 B) &amp; ( 6 C)but with two door openings ( 10 ) on two extended arms.  
     [0030] Fig ( 9 A) shows a top view plan, Fig ( 9 B) shows side elevation and Fig ( 9 C) shows section cut through a core of ‘Cross’ shape pre-cast concrete wall panel complete with pre-cast concrete beam ( 2 ) and pre-cast concrete cornice ( 4 ) finishing.  
     [0031] Fig ( 10 ) shows the section of vertical casting moulding formwork set for casting a pair of pre-cast concrete wall panels as above stated.  
     [0032] Fig ( 11 ) shows a perspective cut out view of the vertical casting moulding framework shown in Fig ( 10 ) Fig ( 11 A) shows an enlarged section of an extendable adapter between two spaced apart edge panels.  
     [0033] Fig ( 11 B) shows an adjustable bottom plate for vertical casting moulding framework set (FIG. 10)  
     [0034] Fig ( 12 ), ( 13 ) &amp; ( 14 ) show a cross-sectional view of pre-cast concrete slab panels of varying widths.  
     [0035] Fig ( 15 A) illustrates the first step in constructing a wall using pre-cast concrete walls whereby a ground floor concrete slab is casted and starter bars are placed at pre-determined positions.  
     [0036] Fig ( 15 B) illustrates the second step after FIG. 15A whereby concrete kicker is constructed and the level is adjusted to receive the pre-cast concrete wall panels.  
     [0037] Fig ( 15 C) shows a section A-A cut through Fig ( 15 B)  
     [0038] Fig ( 16 ) shows a partially completed building wall where pre-cast concrete wall panels show in FIGS. 1A, 1B,  1 C;  4 A,  4 B,  4 C and  6 A,  6 B,  6 C have been erected.  
     [0039] Fig ( 17 A) shows a top plan view of the partially completed building wall shown in FIG. 16.  
     [0040] Fig ( 17 B) shows a partially completed building wall with reinforcement steel bars in some of the hollow cares.  
     [0041] Fig ( 18 ) shows a sectional view of the connecting joint between two adjacent pre-cast concrete wall panels.  
     [0042] Fig ( 18 A) shows a sectional perspective view of a pre-cast concrete wall panel and pre-cast concrete beams with a cap over a hollow core.  
     [0043] Fig ( 18 B) shows a perspective view of a cap that is designed and configured to be placed over a hollow core.  
     [0044] Fig ( 19 ) shows the positioning of the pre-cast floor slabs on the pre-cast concrete beams of the pre-cast concrete panels.  
     [0045] Fig ( 20 ) shows a perspective view of partially completed building where reinforcement steel bars are introduced through the links extending from the pre-cast concrete beam of pre-cast concrete panels shown in Fig ( 19 ).  
     [0046] Fig ( 20 A) is a perspective view of an assembly of pre-cast concrete floor slabs positioned over a plurality of pre-cast concrete wall panels.  
     [0047] Fig ( 21 A) is a sectional view showing in detail the positioning two adjacent pre-cast concrete floor slabs.  
     [0048] Fig ( 21 B) shows two numbers of pre-cast concrete slab panels laid on the pre-cast concrete beams of a pre-cast concrete wall panel.  
     [0049] Fig ( 22 ) shows a perspective view of the assembly of wire mesh and top bars on the pre-cast concrete floor slab before pouring the concrete.  
     [0050] Fig ( 22 A) shows a perspective view of an assembly shown in FIG. 22.  
     [0051] Fig ( 23 ) shows a perspective view of two adjacent linearly aligned pre-cast concrete walls being locked in position in single storey building.  
     [0052] Fig ( 24 A) shows top view plan of pre-cast concrete panels combination by using two numbers of ‘L’ shape and one number of ‘I’ shape whereby the length of ‘I’ shape panel can be adjusted at the casting stage to comply with architectural and structural requirements.  
     [0053] Fig ( 24 B) shows a side elevation view of combination of panels shown in Fig ( 24 A)  
     [0054] Fig ( 25 A) shows the top view plan of pre-cast concrete panels combination by using two numbers of ‘L’ shape, two numbers of ‘I’ shape and one number of ‘T’ shape panel whereby the length of ‘I’ shape can be adjusted at the casting stage to comply with architectural and structural requirements in FIG. 24A.  
     [0055] Fig ( 25 B) shows a side elevation view of combination of panels shown in Fig ( 25 A).  
     [0056] Fig ( 26 A) shows top view plan of pre-cast concrete panels combination by using one number of ‘cross’ shape, one number of ‘T’ shape, one number of ‘L’ shape and two numbers of ‘I’ shape panel whereby the length of ‘I’ shape can be adjusted at the pre-casting stage.  
     [0057] Fig ( 26 B) shows a side elevation view of combination of panels shown in Fig ( 26 A)  
     [0058] Fig ( 27 A) shows a top plan view of pre-cast concrete panels combination by one number of ‘L’ shape, one number of ‘L’ shape with door opening one number of ‘I’ shape panel.  
     [0059] Fig ( 27 B) shows a side elevation view of combination pre-cast concrete panels shown in Fig ( 27 A)  
     [0060] Fig ( 28 A) and Fig ( 28 B) to Fig ( 32 A) and Fig ( 32 B) shows various combinations of pre-cast concrete wall panels by using same method of combination as described from Fig 24 A,  24 B to  27 A &amp;  27 B.  
     [0061] Fig ( 33 A) shows a top plan view of pre-cast concrete wall panels combination by using two numbers of ‘cross’ shape pre-cast concrete panels and one number of ‘I’ shape pre-cast concrete panel with a recess at both sides of the panel and without cores in between.  
     [0062] Fig ( 33 B) shows a side view of the elevation combination of pre-cast concrete wall panels shown in Fig ( 33 A)  
     [0063] Fig ( 33 C) shows section A-A view cut through the ‘I’ shape pre-cast concrete panel in the combination shown in Figs ( 33 A) and ( 33 B).  
     [0064] Fig ( 34 A), ( 34 B) and ( 34 C) show a same combination as Figs ( 33 A), ( 33 B) and ( 33 C) but with one core in the ‘cross’ shape panel. 
    
    
     [0065] Various modular pre-cast concrete panels will now be described. A first pre-cast concrete panel is a planar wall with ‘I’ shape with or without pre-cast concrete beam ( 2 ) and pre-cast concrete cornices ( 4 ) at the top edge (FIG. 1A, 1B and  1 C). The wall includes a plurality of evenly spaced apart cores ( 6 ) extending from the top edge to the-bottom edge of the wall and steel links ( 8 ). The length (x) of the pre-cast concrete wall panel can be varied according to the structural design and architectural requirements of the building.  
     [0066] A second pre-cast concrete panel is a planer wall with ‘I’ shape as described in FIG. 1A &amp; 1B) but with a door opening ( 10 ) (See FIGS. 2A &amp; 2B). A third pre-cast concrete panel is a ‘I’ shaped planar wall as described in FIG. 1A, 1B &amp;  1 C) but with a window opening ( 12 ) (See FIGS. 3A &amp; 3B). A fourth pre-cast concrete panel is a ‘L’ shaped panel (See FIGS. 4A, 4B &amp;  4 C). Each arm of ‘L’ shape panel includes a longitudinal core ( 6 ). The external sides ( 14 ) can be plain or patterned. The upper edges can include pre-cast concrete beam ( 2 ) and cornices ( 4 ) or be without the pre-cast concrete beam or cornice.  
     [0067] A fifth pre-cast concrete panel is ‘L’ shape unit as described in FIG. 4A, 4B &amp;  4 C) but with one arm extended (see FIGS. 5A &amp; 5B). The extended arm can include a door opening ( 10 ) or alternatively include window opening ( 12 ). A sixth pre-cast concrete panel is a ‘T’ shape unit with pre-cast concrete beam and pre-cast cornice as described in Fig  1 A,  1 B &amp;  1 C (see FIGS. 6A, 6B &amp;  6 C). A seventh pre-cast concrete panel is another ‘T’ shape unit where the middle arm in perpendicular relation to the other arm is extended and includes a door opening ( 10 ) or alternatively a window opening ( 12 ) as described in FIG. 1A,1B and  1 C. A eighth pre-cast concrete panel is a ‘T’ shape wall structure with two door openings ( 12 ) (see FIG. 8A &amp; 8B). A ninth pre-cast concrete panel ‘cross’ sectional columnar unit, with at least one bore ( 6 ) in the panel (see FIGS. 9A, 9B &amp;  9 C). All the concrete panels described above may optionally include steel links ( 8 ) secured to the reinforcement steel bars ( 3 ) in the concrete beam ( 2 ) of the concrete wall panels. Further all the panels described above can be casted with or without pre-cast concrete beams and cornices.  
     [0068] It will be appreciated that the individual dimensions of the various parameters such as height, length and thickness of the panel, shapes and designs of the window opening or door opening, patterns on the side wall can be different depending on architectural requirements. The combination selected from the above described pre-cast concrete panels will form any design and any size of a building the except some length of the ‘I’ shaped panel will have to adjusted at the casting stage. Pre-cast concrete panel of other cross-sectional types can be envisaged for other requirements. Such pre-cast concrete panels would be within the scope of this invention.  
     [0069] The mould ( 100 ) comprises of a twin set of mould formworks. Each set of mould formwork comprises of a pair of horizontally placed but spaced apart guide plates ( 102 ) and a pair of side panel plates ( 104 ). The vertical length of the concrete wall panel to be casted can be varied by adjusting the height of the bottom guide plate ( 102 ) upward and downward utilising conventional means known to the art (see FIG. 11B). In the preferred embodiment, the bottom guide plate ( 102 ) is raised or lowered by means of slot and bolt means (see FIG. 11B).  
     [0070] The mould ( 100 ) includes a means to vary the length of the yet to be casted concrete wall panels. The means include a pair of vertical adapter( 106 ) extending from the top of bottom guide plate to under-side of top guide plate ( 102 ). A pair of shafts ( 108 ) are introduced through the holes ( 110 ) in the horizontal guide plates ( 102 ), top and bottom. A plurality of extendable arms ( 112 ) are arranged spaced apart between the shaft and the vertical adapter( 106 ). The extendable arms ( 112 ) extend from one vertical adapter to the other, whereby the distance apart between the vertical adapters can be varied over a pre-determined range. Collapsible cylindrical tubes ( 114 ) are introduced into the holes in the horizontal guide plates. After the wire mesh was placed in position, concrete is introduced into the mould by pouring the concrete across the inverted V shape ledge ( 116 ). The concrete is introduced into both sides of the inverted V shaped ledge ( 116 ) until the moulds are field with concrete.  
     [0071] It will be appreciated that concrete beam ( 2 ) and various designs such as cornices ( 4 ) and patterns ( 14 ) can be incorporated onto the side panels ( 104 ) of the mould. An example of a pattern incorporated into the side panels is shown in FIG. 6B and 6C. The cornices ( 4 ) and the patterned sides ( 14 ) can be provided on one side or on both sides.  
     [0072]FIG. 12, 13 and  14  shown pre-cast concrete slabs of different lengths. Each pre-cast concrete slab is a rectangular slab, with a concrete beam around the perimeter. The concrete beam can include a hollow core if necessary. The perimeter edge further includes pre-cast concrete beam ( 34 ). The heights of the concrete beam and the corresponding depth of the recess can be adjusted at casting stage in accordance with architectural and engineering requirements.  
     [0073] In constructing a building, the pre-cast concrete panels as stated above will be erected, supported and interlocked together by the following methods.  
     [0074] Step 1. Cast the ground floor concrete ( 13 ) and extend the starter bars ( 16 ) out at the predetermined column position ( 15 ). Fig ( 15 A)  
     [0075] Step 2. Constructed the concrete kicker ( 18 ) and adjust the level to receive the pre-cast concrete wall panels and cast-in-situ columns Figs( 15 B)( 15 C).  
     [0076] Step 3. Lift up the pre-cast concrete wall panels and erect to the respective positions. FIG. 16.  
     [0077] Step 4. Insert the reinforcement steel bars ( 19 ) to the respective cores at column positions, and complete with the in fill concrete. Figs( 17 A)( 17 B).  
     [0078] Step 5. Seal up the gaps in between linearly aligned adjacent pre-cast concrete wall panels by fitting in P.V.C gasket ( 20 ) introducing sealant compound ( 22 ) then introducing in-fill concrete. Figure( 18 ). Unused hollow cores in the pre-cast concrete wall panels are covered by inserting P.V.C caps ( 24 ) before pouring the concrete into the mould. Figs( 18 A)( 18 B).  
     [0079] Step 6. Lift up the pre-cast concrete slab ( 26 ) and lay on the pre-cast concrete beams ( 2 ) of pre-cast concrete wall panels. Fig ( 19 )  
     [0080] Step 7. Insert the reinforcement steel bars ( 28 ) through the links ( 8 ) extending from the pre-cast concrete beam( 2 ) of the pre-cast concrete walls. Figure( 20 ) and Fig ( 20 A)  
     [0081] Step 8. Add the wire mesh ( 38 ) to the top of the pre-cast concrete floor slabs and top bars ( 40 ) to the top of pre-cast concrete beams. Figure( 22 ) and Figure ( 22 A)  
     [0082] Step 9. Pour the concrete to the assembly in Fig ( 22 A). All the pre-cast concrete walls, pre-cast concrete beams and pre-cast concrete slabs will be inter-linked and interlocked together to produce a unified overall structure.  
     [0083] Step 10. Repeat the steps  3  to  9  for the next floor.  
     [0084] For single storey, the pre-cast concrete wall panels will be inter-linked and interlocked together by inserting U shape steel bars ( 42 ) after pouring the concrete to column positioned next to each other from two linearly aligned adjacent pre-cast concrete wall panels. Figure ( 23 ).  
     [0085] One edge of a concrete slab is connected to the edge of another adjacent concrete slab by placing the two concrete slabs adjacent to each other and inter-linking pre-cast concrete beam of the pre-cast concrete slab by steel bars ( 33 ). Any crevice or gap at the joint of the two concrete slabs is sealed with a suitable sealant ( 32 ) (See FIG. 21A).  
     [0086] Where a reinforced concrete beam is to be constructed between two adjacent concrete slabs, or where a wall is to be erected from one storey to another, than the each concrete slab ( 26 ) is placed on the concrete beam ( 2 ) of a concrete wall panel. One side of a concrete slab is placed spaced apart from the side of an adjacent concrete slab. A trough is formed by the side edges of the concrete slabs and the top surface of the concrete wall panel. Additional steel bars ( 28 ) are placed in the trough and secured to the steel links ( 8 ) to form a steel cage. Concrete is poured into the trough so formed and allowed to set to form a reinforced concrete beam. If desired additional concrete wall can be erected above this reinforced concrete beam by placing a concrete wall panel over the reinforced concrete. (See FIG. 22)  
     [0087] The advantage of this invention is that the various shapes of pre-cast concrete panels can be assembled, concrete columns are constructed by the introduction of reinforcement steel bars and concrete into the desired cores, cast in-situ reinforcement concrete beams are constructed on top of pre-cast concrete walls and adjacent concrete slab panels, and all reinforcement steel bars can be inter-linked to form a rigid and sturdy building structure. The system provides great flexibility in constructing various types of buildings by the judicious selection of the appropriate types of pre-cast concrete panels. The length of ‘I’ shaped concrete panels can be varied according to architectural requirements and the length adjusted by adjusting the universal moulding formwork set. The Figures ( 24 ) to Figure ( 32 ) showing the plans and elevations for the various type of combination from pre-cast concrete wall panels to form the different designs according to architectural requirements. The specific design of the surface of the wall panel cornices, door frames, window frames and other structures can be easily formed or modified prior to the casting. Furthermore, it is easy to handle the casting and construction and quality is under control at casting plants instead of depending on inconsistent human factor. There is no plastering and no ceiling because the wall and ceiling furnishings can be formed during the process of casting through the moulding formwork set.  
     [0088] The gap between linearly aligned concrete wall panels provides for Fig ( 18 ) for central to central alignment/adjustment and also serves the purpose of expansion join for structural requirement. It will be understood that the gap can also be used as the cast in-situ column by introducing steel bars and concrete into a core formed by two adjacently placed concrete wall panels.