US3455071A

US3455071A - Concrete ceiling plate

Info

Publication number: US3455071A
Application number: US734832A
Authority: US
Inventors: Leopold Muller
Original assignee: Individual
Current assignee: Individual
Priority date: 1968-05-02
Filing date: 1968-05-02
Publication date: 1969-07-15
Anticipated expiration: 1986-07-15

Description

L. MULLER CONCRETE CEILING PLATE.

July 15, 1969 3 sheets-sheetl 1 Filed llay 2. 1968 ad M1212.

July 15, 1969 L. MULLER CONCRETE CEILING PLATE 3 Sheets-Sheet 2 Filed May 2, 1968 Inventor:

Leo/vola! Mr July 15, 1969 l.. MULLER 3,455,071

CONCRETE CEILING PLATE Filed May 2, 1968 3 Sheets-Sheet 5 Fig. 6

United States Patent O Fice 3,455,071 CONCRETE CEILING PLATE Leopold Mller, Kastellweg, 69 Heidelberg, Germany Continuation-impart of application Ser. No. 538,253, Mar. 29, 1966. This application May 2, 1968, Ser. No. 734,832

Int. Cl. E02d 35/00; E04b 1/00 U.S. Cl. 52-127 6 Claims ABSTRACT OF THE DISCLOSURE A light-weight concrete ceiling or floor plate is poured in a mold in which hollow, plastic filler members are individually fastened to the mold bottom to prevent them from moving upward in the concrete mixture which is poured into the mold in a single continuous operation. The filler members are upwardly spaced from the mold bottom and define gaps therebetween, reinforcing steel elements being arranged prior to pouring in the air spaces under the filler members and the gaps between the same.

REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of my copending application, Ser. No. 538,253, filed on Mar. 29, 1966, and now abandoned.

BACKGROUND OF THE INVENTION This invention relates to reinforced concrete floor and ceiling plates having voids in the neutral zone between continuous top and bottom sheets, and particularly to a mold arrangement for making the plates.

The mold arrangements used heretofore in the making of ceiling plates of the type described did not permit the uid concrete mixture to be poured in a single and continuous operation. Typically, a bottom sheet Was rst formed by pouring a portion of the uid concrete mixture into a shallow mold, and permitting the mixture to set until it became shape retaining. Light-weight fillers were then placed on the partly set bottom sheet, and pouring was resumed to complete the operation.

An important object of the invention is the provision of a mold arrangement which permits the concrete mixture for a reinforced light-weight floor or ceiling plate to be poured in a single continuous operation so that the entire plate is set uniformly and simultaneously.

SUMMARY OF THE INVENTION In one of its aspects, this invention resides in a shallow mold in which a plurality of ller members are distributed in a common horizontal plane and define gaps therebetween. The weight of each filler member is substantially smaller than the weight of a body of fluid concrete mixture of the same bulk. Respective fastener assemblies attached to the horizontally extending bottom member of the mold hold the ller members upwardly spaced from the mold bottom and secure them against upward movement with a force sufficient to overcome the buoyancy of the filler members when the filler members are subsequently submersed in the concrete mixture. The filler members and the `bottom of the mold vertically bound air spaces prior to pouring.

A first set of steel reinforcing members is spacedly interposed between the filler members and the mold bottom in the aforementioned air spaces. A second set of steel reinforcing members is partly received in the gaps and projects upwardly and downwardly from the gaps beyond the filler members.

Other features, additional objects and many of the attendant advantages of this invention will readily be appreciated as the same becomes better understood by ref- 3,455,071 Patented July 15, 1969 erence to the following detailed description of preferred embodiments when considered in connection with the appended drawing,

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 shows a filler member for a ceiling or floor plate of the invention in plan top view;

FIG. 2 shows the filler member of FIG. 1 in elevational section on the line II-II;

FIG. 3 shows elements of a mold arrangement of the invention in elevation, the filler members being indicated in phantom view;

FIG. 4 shows the finished floor or ceiling plate in plan section on its median plane through the neutral zone;

FIG. 5 shows the plate of FIG. 4 in elevational section; and

FIG. 6 shows a modified mold arrangement of the invention in fragmentary elevational section.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawing in detail, and initially to FIGS. 1 and 2, there is shown a filler member 2 of the invention which has the approximate shape of a low, square box having beveled edges, slightly domed top and bottom surfaces and an upright tubular passage 6 through its center `between the top and bottom surfaces. The four short vertical edges of the ller member 2 have blind horizontal notches 16.

The filler member 2 is assembled from two separately molded halves of polyurethane foam by cementing. It encloses an annular air space 5 about the passage 6, and its weight is only a fraction of the weight of a body of water of the same bulk. The dimensions of the filler member typically are 2 to 3 feet squareand l to 2 feet thick.

In making a concrete oor of the invention, a Wide and shallow mold is first established in a conventional manner. Only the horizontal, practically imperforate sheet metal or plywood bottom 7 of the mold is seen in FIG. 3, and the mold will be understood to have peripheral upright walls extending beyond the top surface 13 of the oor plate which is to `be formed in the mold.

The filler members 2 are lixedly fastened to the mold bottom 7 in a common horizontal plane in which the filler members are arranged in rectangularly intersecting, spaced rows and columns, as is better seen in FIG. 4 illustrating the completed -floor plate. The filler members are held in position in upwardly spaced relationship to the mold bottom 7 by stiff fastening rings 1 of T-shaped cross section. Each ring 1 is locked to the mold bottom 7 by four narrow wire loops 8 arranged in the surface of an inverted cone coaxial with the ring 1. The wire loops 8 are fastened to each other near the apex of the cone by a washer 9, pass through an opening in the mold bottom 7 and are bent over so as to lock them to the underside of the bottom 7. They cannot be pulled upward from the position shown in FIG. 3.

The gaps between the rows and columns of filler members 2 form a rectangular grid, and the rings 1 and the associated wire loops 8 are attached to the mold bottom 7 at all intersections of the grid. The rings 1 are dimensioned simultaneously to engage the notches 16 in respective edges of the four filler members 2 arranged about the intersection. The rings 1 thus precisely locate the filler members, an air space being bounded vertically between each filler member 2 and the mold bottom 7.

Three sets of reinforcing steel wires or rods are arranged between, below, and above the ller members 2 respectively. The first set consists of a rectangular network of reinforcing members 14 and is horizontally arranged in the mold prior to installation of the filler members 2 so that the reinforcing members 14 are vertically spaced in the afore-mentioned air spaces from the mold bottom 7 and the iiller members 2 when the latter are thereafter fastened to the mold bottom 7 by the rings 1.

The second set consists of steel rods 3 of undulating shape arranged in respective vertical planes in the gaps between adjacent liller members 2. The rods have upper and lower bight portions which project upwardly and downwardly beyond the tiller members 2. The free ends of each rod 3 are hooked through the wire loops 8 and the rings 1 of two fastener assemblies, and are thereby held in position between the iiller members 2 on either side of the rod 3. When all rods 3 are installed, another set of reinforcing members, not seen in FIG 3, but forming a network substantially identical with that of the members 14, may be placed over the upwardly projecting bight portions of the rods 3 and fastened thereto in any desired manner, as by wiring.

Fluid concrete mixture is thereafter poured into the mold to a level 13 well above the top surfaces of the filler members 2 and the upper bight portions of the rods 3. It may be rammed in a conventional manner to improve the appearance of the exposed bottom face of the ceiling plate, and ramming is facilitated by the unobstructed passages 6. After the concrete mixture has been permitted to set, the mold proper may be removed. The floor or ceiling so formed is seen in FIGS. 3 and 4.

It has a top sheet or layer 10 of concrete reinforced by a rectangular network of steel rods or wires 15, and a bottom sheet 11 of concrete similarly reinforced by the steel rods or wires 14. The gaps between the rows and columns of iiller members 2 are filled with rectangularly intersecting concrete ribs 12. The neutral zone of the floor or ceiling has voids formed by the annular air spaces of the filler members. The voids reduce the weight of the floor or ceiling without significantly reducing its carrying capacity. The top and

bottom sheets

10, 11 are locked to each other by concrete in the ribs 12 and by short concrete columns filling the passages 6. The ribs are reinforced by the steel rods 3, not shown in FIGS. 4 and 5, which project into the top and

bottom sheets

10, 11.

If so desired, the air spaces 5 in the filler members 2 may be connected to provide a duct for the iiow of air or for electrical or plumbing conduits. Openings are made in opposite vertical walls of selected filler members 2, and the openings of adjacent iiller members are connected by a tubular former 18 which bridges the gap between the tiller members and encloses a connecting duct 4 in the finished ceiling structure, as is seen in FIGS. 4 and 5.

If the several floors and ceilings of a multiple-Hoor building are to be cast one on top of the other, and thereafter hoisted into position by the construction method commonly referred to as lift-slab method, modilied fastener assemblies of the type shown in FIG. 6 are preferred, and cooperate with modied iiller members 2.

The bottom end of a partly threaded upright spindle -19 is received in an interally threaded tubular insert 20 iixedly fastened in the bottom 7 of the floor or ceiling mold. The spindle 19 is partly enveloped by a thin walled tube 21 which rests on the insert 20 and whose top carries a conically dished, fixedly attached washer 22. A fastening ring 23 is iixedly attached to the washer 22 by four rods 24 which extend obliquely upward from the washer 22 at angles of 90. The washer is held in position by a short tube 25 in the ends of which nuts 26, 27 are iixedly fastened in coaxial alignment of their threads. The top end of the spindle 19 engages the threads of the nuts 26, 27.

The rods 24 and the ring 23 abut from above against the top face of the filler member 2 which is approximately conical, thereby preventing upward movement of the iiller member 2' when buoyed by concrete mixture poured into the mold, as described above. Legs 28 threadedly inserted into the bottom face of the filler member 4 2 maintain the desired spacing between the -ller member 2 and the mold bottom 7.

When the lowermost member of a stack of reinforced iioor or ceiling plates is to be cast, the several filler members 2' are placed on the mold bottom 7 in the desired pattern, the central passage 6' of each filler member being vertically aligned with an insert 20. A spindle 19 is thereafter installed in each insert 20 by means of a screwdriver engaging a slot 17 in the top end of the spindle. The ring 23, rods 24, washer 22 and tube 21, which are tixedly fastened to each other by solder joints, not seen in the drawing, are then slipped over the spindle y19 until the ring 23 rests on the top face of the liller member 2. The tube 25 with its

nuts

26, 27 is next threaded on the spindle 19 until it engages the washer 22, and firmly presses the ring 23 against the iller member 2'.

Reinforcing steel elements are arranged in the mold before and after installation of the filler members 2' in a manner obvious from the preceding description of FIGS. 1 to 5, but not shown in FIG. 6, and iuid concrete mixture is poured into the mold to the level 13 at or slightly below the top edge of the tube 25. When the concrete is set, the spindle 19 is removed by turning its upwardly projecting end, and the mold bottom 7' is thereby released. The openings in the ceiling surface within the permanently installed

tubes

21, 25 may be used for mounting the hangers of a false ceiling or for similar purposes, or they may be plugged at the ends.

When another floor of the same type is to be cast on the first-formed tioor, the top of the latter is covered with a plastic sheet as a separator, and spindles 19 are threadedly inserted in the nuts 27 through small openings pierced in the plastic sheet. Filler members 2 are slipped over the spindles, and another mold arrangement substantially identical with that described in the preceding paragraphs is assembled, the top sheet of the previously cast floor serving as a mold bottom for the second concrete iioor. The procedure may be repeated as often as is needed to produce the desired number of floor plates or slabs.

The

fastening assembly

1, 8, 9 described hereinabove, may obviously be modified to include a central upright spindle analogous to the spindle 19, and may similarly be utilized in the sequential casting of initially superimposed multiple oor plates. Conversely, the fastening assembly shown in FIG. 6 is not limited in its application to floors intended for use in the lift-slab method, but may be employed in the pouring of an individual iioor plate. In that event, the tube 25 and nut 27 may be omitted. The spindle is removed from the underside of the mold lbottom 7', and its bottom end may be provided for this purpose with a slot for insertion of a screw driver.

Other modifiications are contemplated, and may obviously be resorted to by those skilled in the art without departing from the spirit and scope of the invention since only preferred embodiments thereof have been disclosed.

The mold arrangements of the invention are cornpletely assembled prior to the pouring of the fluid concrete mixture, and may be assembled in a workshop remote from the construction site and thereafter transferred if so desired, and if their size and weight permits. The light and very strong floor or ceiling plates of the invention, however, may be built to span wide areas between supporting walls, and are normally assembled on the spot from prefabricated units.

Because the spatial relationship of all members of the mold assembly is lixed in advance, the entire amount of concrete mixture required for forming the floor or ceiling plate lmay be poured in a single continuous operation so that the portion of the mixture occupying the initial air spaces between the

iiller members

2, 2 and the

mold bottoms

7, 7 is still as fluid as the last-poured concrete portion covering the filler members as a top sheet when pouring is terminated.

What is claimed is:

1. In a shallow mold arrangement for pouring a concrete floor plate, in combination:

(a) a horizontally extending bottom member;

(b) a plurality of filler members distributed in a common horizontal plane and defining gaps therebetween,

(1) the weight of each ller member being substantially smaller than the weight of a body of uid concrete mixture of the same bulk,

(2) each ller member having horizontally eX- tending top and bottom faces and being formed with a passage vertically extending therethrough between said faces;

(c) a plurality of fastening means attached to said bottom member and respectively holding said ller members upwardly spaced from said bottom member and securing the -ller members against upward movement with a force sufcient to overcome the buoyancy of said members when the filler members are l submerged in said concrete mixture,

(l) each filler member and said bottom member vertically bounding an air space therebetween (2) each fastening means including (i) an elongated fastening member extending through the passage of the associated filler member and having a lower terminal portion threadedly received in a corresponding threaded opening of said bottom member and an upper terminal portion upwardly projecting from the associated filler member,

(ii) abutment means on said fastener member abuttingly engaging the top face of the associated filler member,

(iii) nut means on said upper terminal portion for retaining said abutment means in engagement with said top face, and

(iv) protecting tube means enveloping said fastener member substantially from said bottom member to said nut means;

(d) a rst set of steel reinforcing members spacedly interposed between said filler members and said bottom member in said air spaces; and

(e) a second set of steel reinforcing members partly received in said gaps and upwardly and downwardly projecting from said gaps beyond said filler members.

2. In an arrangement as set forth in claim 1, said upper terminal portion being threaded, and said nut means including a nut member threadedly engaging the threads on said upper terminal portion.

3. In an arrangement as set forth in claim =1, each filler member having a vertically extending edge and being formed with a transverse notch in said edge, a portion of said fastening means horizontally extending into said notch.

4. In an arrangement as set forth in claim 1 said second set of steel reinforcing members including a plurality of rod members of undulating shape, each rod member having a plurality of bight portions projecting above said filler members and a plurality of bight portions projecting below said filler members.

5. In an arrangement as set forth in claim 1, said bottom member having an upwardly directed substantially planar face.

6. In an arrangement as set forth in claim 1, said ller member sealingly enclosing a body of air.

References Cited UNITED STATES PATENTS 640,176 1/1900 Bremer 52-381 929,470 7/ 1909 Neil 52-382 X 1,160,384 11/1915 Crane 52-577 1,206,752 11/1916 Davis 52-382 1,775,234 9/1930 Brostrom 52.-381 X 2,234,784 3/ 1941 Stolz 249-35 X 2,618,960 11/1952 Orzel 52-57'6 2,811,850 11/1957 Clary 52-220 X 2,964,821 12/1960 Meehan 52-410 X 3,216,157 11/1965 Pinter 52-126 X 3,276,176 10/ 1966 Jonsson et al. 52-577 X FOREIGN PATENTS 107,186 9/ 1927 Austria.

ALFRED C. PERI-IAM, Primary Examiner U.S. Cl. X.R.