LOST MOULD ELEMENT FOR MANUFACTURING REINFORCED CONCRETE FLAT SLABS

Abstract: The present invention is concerned with a lost mould element for manufacturing conventional reinforced concrete flat slabs, which is intended, when used together with others mould elements for creating voids and for allowing the moulding of beams, characterised in that the said mould element (6, 9, 26, 29) is made of recycled plastic material, having the shape of a hollow box, substantially of flat prismatic shape, preferably, rectangular or square, which is formed from to half boxes, an upper one (9, 29) and a lower one (6, 26), joined together removably, each mould element has sides or lateral walls with profiles which define together with others sides or lateral walls of the others mould elements, "I" profiled channels or "I" degenerated profiled channels for moulding beams, and between the sides or lateral walls are arranged steel rod attachment and distribution supports (5, 5a; 25, 25A) for securing the steel rods (4; 24), for reinforcement of said "I" or "I" degenerated profiled beams (12; 32). The mould elements of the present invention can be used in building industry.

Description: "LOST MOULD ELEMENT FOR MANUFACTURING REINFORCED CONCRETE FLAT SLABS" The present invention concerns to lost mould elements for manufacturing reinforced concrete flat slabs. The reinforced concrete flat slab is a flat plate designed to span in two directions. The present invention is directed to provide lost mould elements, preferably, of recycled plastic material, for manufacturing reinforced concrete flat slabs. The mould elements of this invention are lost mould elements, this is, they are intended to be incorporated into the flat slabs and, thereby they also solve the environmental problem of the disposal of plastic material waste. The mould elements according to the present invention are intended to create voids inside of the reinforced concrete flat slabs and, hence to light the flat slab, as well to allow the moulding of beams reinforced with steel rods, which are defined by the sides or lateral wall of the mould elements and they include reinforcing steel rods in their interior. The inclusion reinforcing steel rods is possible thanks to the supporting parts for the steel rods, which are connected to the mould elements. The use of voids and beams in the manufacturing of conventional reinforced concrete flat slabs has as object to provide stronger and lighter reinforced concrete flat slabs. The casting of the reinforced concrete flat slabs, with this type of mould elements rises two orders of problems. The first one is that mould elements are prone to float in the fresh concrete, because the mould elements are hollow and the difference density between the mould elements and the fresh concrete and additionally to the bonding of the fresh concrete to the mould. The second one is the evacuation of the air during the casting, as sometimes are created air chambers near the bottom of the mould elements, when during the casting of the flat slab vibration is applied to the concrete mass. For solving the fist problem type, the mould element according to the invention has attachment means for securing the mould element, which not allow his floatation, and grooves and substantially cylindrical hollow parts, which allow that the concrete runs all around the surface involving of the mould element and being better bonded to it. For solving the second problem type, according to the invention openings and gaps are arranged for air evacuation, which allow the air circulation through the mould element and hence its easier evacuation. According the first variant of the present invention a lost mould element is provided for manufacturing conventional reinforced concrete flat slabs, which is intended, when used together with others mould elements, for creating voids and allowing the casting of reinforced beams, wherein the mould element, is made of recycled plastic material, having the shape of a hollow box, substantially of flat prismatic shape, preferably, rectangular or square, which is formed from to half boxes, joined together, an upper one and a lower one, and with a base arrangement, the main lower face or bottom being in the lower half box spaced apart of the said base arrangement at least the said main lower face presenting grooves, the said sides or lateral walls and said base arrangement of said mould element having skew notches, for several steel rod attachment and distribution supports, the attachment means can also be secured in said interior face of said half box and there being substantially cylindrical hollow connection parts in the internal faces of the said half boxes, which provide to the mould element a good compression and deformation strength, the base arrangement being attached secured to the lower half box with skew notches, which allow the existence of predetermined gap, for air circulation, there being further two small openings in said upper half box closed with a very thin plastic film, which allow whenever is necessary the air circulation. Each mould element has sides or lateral walls with profiles, which define together with others sides or lateral walls of the others mould elements, "I" profiled channels or "I" degenerated profiled channels for casting beams. The mould element for beams according with the present invention presents spacer feet in the lower face of lower half box. The junction between the two half boxes of the mould element is removable. According to the present invention the mould element has such dimensions and geometry to allow the easier control of all dimensions requested by the flat slabs in which they are going to be included. The mould element has grooves, which allow for better flowing and bonding of the fresh concrete in the areas more strangled, this is, the lower portion of the mould element. According a second variant of the present invention is provided a lost mould element, which is made of recycled plastic material, having the shape of a hollow box, substantially of flat prismatic shape, preferably, rectangular or square, which is formed from two half boxes, joined together, a upper one and a lower one, the sides or lateral walls having a corrugated configuration, for increasing their strength, the main upper and lower faces presenting skew notches and the lateral walls of said mould element presenting holes for nesting the steel rod attachment and distribution supports. The main faces present at least two grooves parallel one another and parallel to a edge of the main face of the mould element and several spacer feet, perpendiculars to said faces, arranged evenly upon the its surface, each one having at least one flange with a recess for receiving an steel rod or facility. The internal faces of said half boxes has substantially cylindrical connection hollow parts, which provide to the mould element a good compression and deformation strength, there being further small openings in said mould element, which allow whenever is necessary the air circulation. Each mould element has sides or lateral walls with profiles, which define together with others sides or lateral walls of the others mould elements, "I" profiled channels or "I" degenerated profiled channels for casting beams, the spacing between each one of said mould elements is determined by the steel rod attachment and distribution supports. The junction between the two half boxes of the mould element is removable. According to the present invention the mould element has such dimensions and geometry to allow the easier control of all dimensions requested by the flat slabs in which they are going to be included. The mould element has grooves, which allow for better flowing and bonding of the concrete in the areas more strangled, this is, the lower portion of the mould element. The invention will be now explained in more detail by mean of examples with the help of the appended drawings, in which: Fig. 1 is a sectional view of a reinforced concrete flat slab, wherein are incorporated the mould elements of a first embodiment of the first variant of present invention, as well as two enlarged sectional details of said mould elements; Fig. 2 is a bottom perspective view of the mould element according the first embodiment of the first variant of present invention; Fig. 3 is a bottom plan view of the half box of the mould element of Fig. 2; Fig. 4 is a side view of mould element of Fig. 2; Fig. 5 is a top perspective view of the mould element of Fig. 2; Fig. 6 shows three partial sectional views of reinforced concrete flat slabs, which use the mould elements of Fig. 2; Fig. 7 shows a enlarged detail correspondent to Fig. 8; Fig. 8 is a bottom perspective view of another embodiment of the first variant of the present invention; Fig. 9 is a sectional view of a reinforced concrete flat slab, in which are incorporated the mould elements of an embodiment of the second variant of present invention; Fig. 10 is a perspective view of a mould element of an embodiment of the second variant of present invention; Fig. 11 is perspective view of the outside of the half box of the mould element of Fig. 10; Fig. 12 is a perspective view of the inside of the half box of the mould element of Fig. 10; Fig. 13 is a side elevation view of the mould element of Fig. 10; Fig. 14 is a perspective view of the upper steel rod attachment and distribution support, used by the mould element of Fig. 10; Fig. 15 is a perspective view of the lower steel rod attachment and distribution support, used by the mould elements of Fig. 10; and Fig. 16 is a perspective view of the another embodiment of the upper steel rod attachment and distribution support, used by half boxes of the mould element of Fig. 10; Fig. 17 is another sectional view of another reinforced concrete flat slab, wherein are incorporated half boxes of the mould elements of the embodiment of the second variant of the present invention. As shown in the Fig. 1 , the reinforced concrete flat slab manufactured with the mould elements according with the first variant of present invention, is composed by a first layer of concrete, arranged between a floor layer 1 and a sheathing 11 , within of the concrete layer being arranged a set of mould elements 6, 9, spaced from said sheathing 11 , a metallic screen 3 preferably electric welded netting type, between the upper faces of said mould elements 6, 9 and spaced apart from both said faces and said floor layer 1. The set of mould elements 6, 9 form together laterally channels for casting the beams which channels define preferably beams 12 with "I" profiles or "I" degenerated profiles, before the casting of fresh concrete being mounted in said channels for casting the beams 12, by engagement in lateral edges of the mould elements and in the base arrangement 10, steel rod attachment and distribution supports 5, for securing the reinforcing steel rods 4 at least in two areas of said channels for casting the beams 12. In Fig. 1 can also be seen in detail the configuration of the engagement between the holes of the main face of the lower half box 6 and the vertical engagement spacers 7 (Fig. 4) and the gap 19, existent between them, as well as the holes for air evacuation 20 in the main face of said upper half box 9. According Fig. 2 the mould element 6, 9, manufactured of recycled plastic material having the shape of a hollow box, substantially of flat prismatic shape, preferably, rectangular or square, which is formed from to half boxes, a upper one 9 and a lower one 6, joined together removably, for example, by way of several peripheric skew notches 14, the said main face of the lower half box 6 having connected a base arrangement 10, comprised of a screen and a plurality of nesting vertical spacers 7 (Fig. 4), which engage in holes existent in the said main face of said lower half mould box 6. As shown in Fig. 3 the main face of said lower half box 6 presents four holes for inlet in the substantially cylindrical hollow parts 8, a plurality of protuberances or nails 15 evenly arranged which cause a better bonding of the concrete in the mould element. As can been seen in Fig. 5 the main face of said upper half box 9 has grooves similar to the grooves 18 existent in main face of said lower half box 6 and four holes in correspondence to the said substantially cylindrical hollow parts 8. Can also be seen several skew notches 16 for the steel rod attachment and distribution supports 5. In the three views of Fig. 6 is shown the formation of the "I" profiles or "I" degenerated profiles. Figs. 7 and 8 show an alternative embodiment of the first variant of the mould element of the present invention. As can be seen the arrangement of the grooves 18a is different, as well as the number of 5 inlet holes for the substantially cylindrical hollow parts 8a, furthermore the base arrangement 10a, do not include a web but only three spacer feet 10a. In this case do not exist a screen as in the embodiment anterior, the steel rod attachment and distribution supports 5 are fitted in the skew notches 16a. As shown in Fig. 9 the reinforced concrete flat slab manufactured with the mould elements according to an embodiment of the second variant of the present invention, is composed by a first layer of concrete, arranged between a floor layer 21 and a sheathing (not shown), inside of concrete layer being arranged a set of mould elements 26, 29, spaced from said sheathing by lower feet 27 and the base of the steel rod attachment and distribution supports 25A. The set of mould elements 26, 29 forms together laterally channels 32 for moulding beams, which channels define preferably beams 32 with "I" profiles or "I" degenerated profiles, before the casting of fresh concrete being mounted in said channels for moulding the beams 32, by engagement in the sides and in the main faces of the mould elements, steel rod attachment and distribution supports 25, 25A for securing the steel rods 24 at least in two areas of the said casting beam channels 32. Of course, the mould elements 26, 29 can be used instead of the said mould elements 6, 9 in the embodiment of fig. 1 As shown in Figs. 10, 11 , 12, and 13 the mould element 26, 29, which is made of recycled plastic material, having the shape of a hollow box substantially of flat prismatic shape, preferably, rectangular or square, which is formed from to identical half boxes, a upper one 29 and a lower one 26, joined together removably, for example, by way of several pe pheric skew notches 34, and a plurality of feet 27, disposed perpendicularly and evenly in upper and lower faces of said mould element 26, 29, each of them having two perpendicular flat flanges which has each a recess with a keyhole shape for receiving an steel rod or facilities. As shown in these figures the main faces of the mould element 26, 29 present five inlet holes for the substantially cylindrical hollow parts 28 there being further small openings 31 in said mould element, which allow whenever is necessary the air circulation. The main faces of the mould element 26, 29 present further grooves 38 and three pairs of holes 22 in correspondence with the each edge of the main upper and lower faces of said mould element for engagement of the upper steel rod attachment and distribution supports 25 (holes 22 in the main face) and lower steel rod attachment and distribution supports 25A (holes 22 in the lateral wall). In Figs. 1 1 and 12 can be seen the substantially cylindrical hollow parts 28. In Figs. 14 and 15 are shown respectively the said upper and lower steel rod attachment and distribution supports 25, 25A, the said upper support 25 being comprised by a plastic moulded profile, with its ends configured to engage in holes in the upper main face of said mould element as seen in Fig. 9, and the said lower support being comprised by a plastic moulded profile with its ends configured to engage in holes in the lateral walls of the mould element, as seen in Fig. 9. The said upper support in the configuration shown in Fig. 14 has recesses for receiving the said steel rods 24 and the configuration shown in Fig. 15 has also recesses for receiving the said steel rods 24. In another embodiment shown in fig. 16 the upper support 25' has three recesses and is to use with the half boxes 26 in the embodiment shown in Fig. 17. Although the present invention has been shown and described with reference to the preferred embodiments must be immediately understood that modifications can be done within the scope of the appended claims and what is obvious to those skilled in the art, when are taken into consideration the teachings provided by the present specification.

Claims: CLAIMS 1 - Lost mould element for manufacturing conventional reinforced concrete flat slabs, which is intended, when used together with others mould elements for creating voids and for allowing the casting of beams, characterised in that the said mould element (6, 9; 26, 29) is made of recycled plastic material, having the shape of a hollow box, substantially of flat prismatic shape, preferably, rectangular or square, which is formed from to half boxes, an upper one (9, 29) and a lower one (6, 26), joined together removably, each mould element has sides or lateral walls, with profiles, which define together with others sides or lateral walls of the others mould elements, "I" profiled channels or "I" degenerated profiled channels for casting beams, and between the sides or lateral walls are arranged steel rod attachment and distribution supports (5, 5a; 25, 25A) for securing the steel rods (4; 24), for reinforcement of said "I" or "I" degenerated profiled beams (12; 32). 2 - Lost mould element according to the claim 1 , characterised in that it has an base arrangement (10, 10a), the lower main face being in the bottom of the said lower half box (6), spaced apart of said base arrangement, at least said lower main face of said lower half box (6) having grooves (18), the lateral walls and said base arrangement of said mould element having skew notches (16, 17), for the different steel rod attachment and distribution supports (5, 5a), for securing the steel rods (4), the protuberances or nails (15) being secured in said lower face of said lower half box (6), there being substantially cylindrical hollow connecting parts (8) in the internal faces of said half boxes, which provide to the mould element (6, 9) with a good compression and deformation resistance, said base arrangement (10) being secured to the lower half box by means of skew notches, which allow the existence of a predetermined gap (19) for the air circulation, there being also small openings (20) in said upper half box, covered with a very thin plastic film, which allow whenever is necessary, the air circulation. 3 - Lost mould element according to the claims 1 and 2, characterised in that it has spacer feet (10a) in the said main face of said lower half box (6). 4 - Lost mould element according to the claims 1 , 2 and 3, characterised in that the junction between the said two half boxes (6) and (9) is removable and it includes skew notches (14). 5 - Lost mould element according to the claims 1 , characterised in that the side or lateral walls has a corrugated configuration, for provide a great resistance to them, and the main upper and lower faces and the said lateral walls of said mould element (26, 29) has holes (22), for the steel rod attachment and distribution connection supports. 6 - Lost mould element according to the claim 5, characterised in that the said corrugated configuration consists of ridges (33), said ridges being triangular, and arranged in such a way that the bases of the triangles are disposed close of the separation plan of said two half boxes (26) and (29). 7 - Lost mould element according to the claims 5 and 6, characterised in that the said main faces has at least two grooves (38) parallel one another and parallel to a edge of the main face of the said mould element (26, 29), and several spacer feet, perpendiculars (27) to said main faces, arranged evenly on its surface, each one having at least one flange with a recess for receiving a steel rod. 8 - Lost mould element according to the claims 5, 6 and 7, characterised in that the said and in that in internal faces of the said half boxes are disposed substantially cylindrical hollow connecting parts (28), which provided to the mould element a very good compression and deformation resistance, there being also small openings (31 ) in said half boxes which allow whenever is necessary the air circulation.

Inventors: FEBRA ANTONIO FRANCISCO, FEBRA, ANTONIO, FRANCISCO
Applicants: FEBRA ANTONIO FRANCISCO, FEBRA, ANTONIO, FRANCISCO
Application year: 2000
Main classification: B28B23
IPC codes: B28B7, B28B23, E04B5, E04C5