US2062944A

US2062944A - Grid structure for floors and the like

Info

Publication number: US2062944A
Application number: US550346A
Authority: US
Inventors: Sloan Lon
Original assignee: Individual
Current assignee: Individual
Priority date: 1931-07-13
Filing date: 1931-07-13
Publication date: 1936-12-01
Anticipated expiration: 1953-12-01

Description

Dec. 1, 1936. SLOAN Y 2,062,944

" GRID STRUCTURE FOR moons AND THE LIKE Original Filed'July 15, 1931 s sheets-sheet 1 mm M Dec. 1, 1936. SLQAN 2,062,944

GRID STRUCTURE FOR FLOORS AND THE LIKE Original Filed July 15, 1931 3 Sheets-Sheet 2 fzz/arzi'orr LOwQSZOcZm Dec. 1, 1936. SLOAN 2,062,944

GRID STRUCTURE FOR FLOORS AND THE LIKE Original Filed July 13, 1931 3 Sheets-Sheet 3 Patented Dec. 1, 1936 UNITED STATES PATET QFIQE GRID STRUCTURE FOR FLOORS AND THE LIKE Lon Sloan, Chicago, 111.

11 Claims.

The present invention relates to grid structures for composition floors, pavements, stair treads, bridge surfaces and the like. The utility of the present invention is probably realized to the greatest extent in armored floors wherein the wearing surface is a combination of interspersed metallic areas and concrete areas, and accord ingly I shall make principal reference to that embodiment in describing the invention, but, as will hereinafter appear, the invention is not limited thereto.

In concrete floors laid in factories, warehouses etc. where there is a great amount of heavy load trucking over the floor, and also in bridge floors,

1-5 it desirable to have metallic areas projecting up to the surface of the concrete at distributed points for bearing some of the trucking load whereby to minimize wear of the floor surface. The metallic areas or armoring units usually 20 constitute part of an open-work grid structure into the spaces of which the concrete or other plastic material is flowed. The type of grid structure now most commonly used consists of a heavy section composed entirely of cast-iron.

25 These prior grid structures are of limited utility and are objectionable for different reasons. The weight and cost of each section is objectionable because of the large mass of cast-iron in each section which is not available as armoring area 30 at the surface of the floor. Furthermore, the

absolute rigidity of these prior cast-iron grid sections precludes their use in saucer floors where all surfaces must slope down to a drain, or in situations where the floor has a crown or slope extending up or down to a stationary machine or along a ramp. Also, because of their great weight and the large mass of interconnecting cast-iron extending throughout the section it is a very laborious operation to handle these grids,

40 and the cutting of marginal grids at the wall line or around a machine, column etc. is an exceedingly dimcult operation which can only be accomplished with a heavy sledge and cold chisel or with an acetylene burning torch. These rigid 45 cast-iron grids are also exceedingly difficult to cast because of their tendency to warp.

Another type of structure now in use is composed of steel bars interlocked together in the form of an openwork grid section. This type is 50 usually more expensive than the solid cast-iron grid. It is also exceedingly diflicult to trim these grids to a wall line or around columns or other floor projections. The majority of these fabricated steel grids are rigid, but where they have 55 flexibility such flexibility only lies in one direction in the section and hence the section cannot be dished or sloped in both directions for use in saucer floors or other situations having sloping floor surfaces at difierent angles. Moreover, in many situations the fabricated steel grid does 5 not stand up under abrasive Wear as well as the cast-iron grid, and in factories and other locations where acid conditions exist the steel grid is much inferior to the cast-iron grid which is substantially acid-proof. 10

The general purpose of my invention is to provide a grid structure which will avoid all of these objections. To this end, one of the principal objects of the invention is to provide a grid structure wherein the armoring elements exposed at the surface of the floor are of the desired material for meeting the specific conditions of the particular installation and wherein these armoring elements are interconnected by a metallic network which is of such a nature that it may be shaped in any direction for forming any slope or curvature in the grid and which may be readily out in trimming the grid sections to a wall line, floor projections etc. In the preferred form of my invention where the structure must be capable of withstanding heavy wear and acid conditions and must also be cheap to manufacture I employ castiron armoring elements all interconnected by a ductile network composed of wires, or flat metallic strips, or possibly expanded metal, the latter consisting of a perforated thin sheet metal plate.

In this regard, another object of the invention is to provide an improved method of connecting the armoring elements with the flexible network. In the preferred manner of doing this the flexible network is placed between the cope and drag of a mold conforming to an entire grid section, and the armoring elements are cast in the mold to envelop portions of the network and to have molecular cohesion therewith. If desired, the network may be welded to the rigid armoring elements, or these elements may be provided with suitable holes or openings through which portions of the network pass or in which they are secured. The cost of the flexible network is less than the cost of the interconnecting mass of cast-iron heretofore extending between the armoring elements of the solid type of cast grid, and hence the present grid is less expensive to manufacture, in addition to its other advantages 5 of being easier to handle because of its lighter weight, being capable of shaping in any desired direction for any floor slope or curvature, and being easy to cut and notch out in trimming to wall lines, floor projections etc. This flexible network can be cut by wire cutters, tin shears or the like. The flexible network is preferably disposed adjacent to the base portions of the armoring elements so that the latter can wear down practically to these base portions before the network is exposed or the armoring elements can become loosened. This construction increases the side wall area of the armoring elements for more effective bonding with the concrete, and the network constitutes a reenforcing for the concrete.

It is often desirable to have the armoring elements constructed with various ornamental outlines or in the form of monograms or symbols representative of the factory name or place of installation, and in this regard the present grid and method of constructing the same has the further advantage of permitting ready variation in the design of the armoring elements. In the laying of these grid sections the construction thereof also facilitates the matching or proper grouping of the armoring elements or lines of ornamentation of adjacent sections so that the floor pattern can be laid out uniformly and easily.

Other objects and advantages of the invention will appear in the following description wherein I have described a preferred embodiment and a preferred method of making the grid and of carrying the invention into effect. In the drawings accompanying said description:

Figure 1 is a top plan view of a portion of a grid section in which the armoring elements are secured to a flexible network in the form of a perforated sheet metal plate;

Figure 2 is a fragmentary transverse section taken approximately on the plane of the line 2-2 of Figure 1;

Figure 3 is a top plan View of a portion of a grid section in which the armoring elements are secured to a flexible network constructed of wires crossing in the form of a wire mesh;

Figure 4 is a section taken approximately on the plane of the line 4-4 of Figure 3;

Figure 5 is a top plan view illustrating a portion of a finished floor armored and reenforced with my improved grid structure;

Figure 6 is a fragmentary sectional view through. a dished or curved floor surface showing the armoring elements and network in section;

Figure '7 is a sectional View through a mold, partly broken away, illustrating the manner of casting the present grid section therein, the armoring elements being cast to a flexible network or mesh such as that illustrated in Figure 1;

Figure 8 is a fragmentary sectional view through a portion of the mold after the pattern cast is made and illustrating a modified form of tying mesh or network;

Figure 9 is a fragmentary sectional view similar to Figure 8 illustrating the casting of the armoring units to a wire mesh form of network such as I have illustrated in Figure 3;

Figure 10 is a fragmentary cross-sectional view through the grid taken on the plane of the line Ill-40 of Figure 1, as it appears when embodied in a floor structure;

Figure 11 illustrates a method of connecting adjoining sections;

Figures 12 and 13 are plan and vertical sectional views respectively of a construction wherein the network is disposed generally below the plane of the armoring units;

Figures 14 and 15 are plan and vertical sectional views respectively of a different construction; and

Figures 16 and 17 are plan and vertical sectional views respectively of another construction.

Referring to the drawings, the grid section as a whole is indicated by the numeral l5, and it comprises a plurality of cast armoring elements or sections I6, which may be of various forms or designs as desired, all secured to a metallic network generally indicated at II.

In the preferred embodiment the metallic net.- Work I 7 is embedded in the metal of the cast iron figures during the casting operation, as will be more fully described hereinafter. The entire grid section I 5 is preferably rectangular in outline and may be of any desired dimensions convenient for handling; which I have found to be preferably in the neighborhood of from 12 to 20 inches on a side. The flexible network illustrated in Figures 1, 2 and '7 consists of a thin sheet metal plate Ila of the approximate dimensions of the grid section. This plate is reticulated as by having openings punched therein to leave longitudinally and transversely extending sheet metal strips; or the plate may consist of a section of so-called expanded metal wherein the metal is slitted or punched and then stretched.

In Figures 3 and 4 I have illustrated a flexible network I! comprising longitudinally and transversely extending wires Ill) and I10, and in Figure 8 I have shown the network or mesh II as comprising a plurality of longitudinally and transversely extending separate fiat metal strips or ribbons 11d and He which overlap each other as shown. Where the wires or flat strips cross each other they may be given oppositely offset bends, as shown in Figure 9, so that all of the strips or wires lie in the same plane and the wires or strips may be interwoven to form a selfsustaining large mesh screen for greater facility of handling in the casting operation. However, this is not essential because the casting opera tion hereinafter described can be performed with one series of wires or strips spaced above or below the other series. Furthermore, I wish it to be understood that it would fall within the scope of my invention to provide tying members extending only in one direction. Also where it is desired that the grid section have a slightly greater degree of stiffness for ease of handling or any other reason, small angle bars or T- bars may be used instead of the wires or ribbon. stock. By the use of this network a flexible grid is provided,-that is to say, a grid which may be bent so as to adapt it for use in dished or curved surfaces, as the network is light enough that it can be bent whereby the grid may be made to conform to such curved surfaces. Even where the network is composed of small stock angle bars or T-bars the grid section can be pounded to any desired curvature or slope. In. Figure 6 of the drawings I have illustrated in section a portion of my improved grid embodied in a floor having a dished upper surface.

The grid is cast in a suitable mold, such as that shown in Figures '7, 8 and 9, and iron, steel, brass or any metal desired that is suitable for the purpose intended, may be used to form thearmoring elements l6 of the grid. The drag of the mold is indicated at l8 and the cope at I9. After the mold cavity is formed in the drag and cope, together with the usual pouring sprue holes and interconnecting gateways, the cope and pattern are removed, as is usual in molding practice. The network H or other suitable tie members are then placed in position in the drag as shown in Figures 8 and 9, portions of such network extending across the cavities in the mold which are to be filled during the casting operation. Suitable provision is made in the pattern for making an imprint in the sand of the drag so that the mesh or tie members may be placed and held. in proper position in the drag, whereby when the casting is poured the mesh will be embedded in the metal of the various armoring elements [6 of the grid. After the mesh is placed in position, the cope is replaced on the drag and the mold is ready to be poured. The usual pouring sprue openings are indicated at 2i in Figure 7 and such openings extend through the cope down to the upper side of the pattern cast. In this connection I also contemplate providing an addition to the usual pouring openings 2i, one or more secondary pouring openings such as are indicated at 22 which extend down through the cope and through the drag to the lower portions of the mold cavities, as shown in Figure 7, thereby providing for a more uniform flow and distribution of the molten metal tothe lower parts of the mold cavities during the pouring operation. Attention is directed to the fact that the bottom side of the castings in the mold are the top side of the grid in use. By thus casting the grid in reverse a clean smooth wearing surface of close density is obtained to present at the upper wearing surface of the floor, because there is less liability that bubbles will be formed in such lower surface in the mold which is the upper wearing surface in use. This is because blow-holes are more likely to occur in the top part of the casting and also because impurities in the iron or other metal that is being cast tend to rise to the surface, which surface is the upper surface in the mold but is the lower surface of the grid in its application to the floor structure. The sprues 24 formed in the pouring openings 2! and 22 during the casting operation are removed from the finished grid structure. By providing gateways (resulting in the gates 25) extending in different directions from one mold cavity to another in the fiask all of the considerable number of armoring elements H5 in a grid section can be formed by only a few pourings. As shown in Figures 1 and 2, the metallic gates 25, formed by these gateways and serving to interconnect all or substantially all of the cast units, are of light sectional thickness. In cast iron these gates can be readily broken between the cast figures I6. In cast steel, brass or the like they are also so proportioned of light sectional thickness that they can be readily broken for forming a sharply curving surface or easily cut for trimming a grid section 15 to meet a wall line, floor obstruction etc. However, in the latter metals these light gates 25 may if desired be bent considerably in shaping the grid section to dished, curved or angular floor surfaces without breaking the gates. In practice the gates 25 are preferably left intact and straight, up to the time of final positioning in the floor structure because they lend a desired stiffness to the grid section which enables it to be handled more easily in shipping, packing etc.

It is to be noted that the network I! is embedded in the various armoring castings N5 of the grid adjacent to the cope side of the mold as shown in Figure '7 which, as before described, is the underside of the finished grid section I5 as used in the floor structure, also that the side walls 26 of those portions of each casting l6 formed in the drag l8 converge downwardly towards each other approximately from the longitudinal medial plane of the network I1, and that the side Walls 2'! of those portions of each casting I6 formed in the cope l9 converge upwardly towards each other from approximately the plane of the network II. This positioning of the network l'l adjacent to the upper surface of the casting as shown in said figure facilitates pattern construction, the forming of the mold and the drawing of the cope of the flask, as less depth of draw is necessary. The converging of the side walls 26 of the castings of the grid section from the plane of the network to the bottoms of the castings as shown in the mold serves a double function, i. e., it provides draft on the sides of the pattern to permit its ready removal from the sand, and it also serves to provide anchorage for the finished grid in the cement or other material forming the body of the door. By embedding the tying mesh in the grid adjacent the cope side as shown in Figure 7, which is the under side of the grid when in use as above mentioned, the wearing depth of the grid before the network is exposed or broken is greatly increased, and furthermore a maximum length of taper for anchorage of the grid in the plastic material of the floor is provided. Furthermore, this positioning of the network I! also reduces the turning moment of the cast elements It around their points of attachment to the network, thereby reducing the liability of warping or curling up of the grid section under extremely heavy rolling loads.

In the most desirable form the gates 25 are cast in the same plane in which the network I! is positioned, but preferably these gates comprise spans through which the network does not extend, as best shown in Figure 1, so that the gates may be more readily broken if the breakage thereof is desirable. The armoring elements 16 and the network ll become an integral structure by virtue of the molecular fusion or cohesion occurring between the two in the casting opera tion.

The cast units l6 of the grid section may be of any desired design and may be grouped in any straight line, diagonal or circular relation in the grid section. In Figure 3 I have shown a characteristic letter B figuring in the design, which is illustrative of any letter, monogram or symbol which may be appropriate to the installation. In this regard I contemplate as another feature of my invention the provision of a master pattern on which different designs for the cast units l6 may be easily interchanged. That is to say the matrix or plate of the pattern will remain standard and will carry the guide lines and possibly certain figures of the floor design, while the pattern sections representing the individually characteristic cast units will be detachable and interchangeable thereon for using different designs.

My improved grid structure also enables the laying of a uniform floor pattern or the particular grouping of the elements of a design to be more easily accomplished. If extending portions of the network ll of two adjacent grid sections tend to interfere with the accurate matching and alignment of the figures in the two grid sections these portions of each network can be easily cut off or bent to one side.

In some instances it may be desirable to connect adjacent grids and this can be accomplished by the construction shown in Figure 11. The

ends of two or more network members on each side of the grid section may be provided with eyes 29, and such eyes of adjoining grid sections may be coupled together by cotter pins 3| or any other suitable connecting devices.

In the laying of the floor, after the slab or baseportion 35 of the floor has been formed and has set for say two or three weeks, as is customary in the building up of concrete floors of this type, a layer of so-called stiff cement is placed on the slab and thereupon the grid sections l5 are placed in position and tamped down into said stiff cement; after which, before the stiff cement has set, the grouting or thin mix of cement forming the top surface of the floor is poured into the grid sections l5 and between the several armoring elements l6 and smoothed off or floated in as is the usual practice in the laying of cement pavements and floors. This layer of stiff cement together with the grouting forms the upper cementitious layer 36 of the floor, as illustrated in Figures 5, 6 and 10.

When it is desired to shape the grid sections l 5 to conform to a saucer floor sloping to a drain, or to conformto a ramp, crown or any other curvature in the floor, this may be accomplished in different ways. For example, the gates 25 interconnecting the armoring elements l6 may be broken in the grid section before it is laid, whereby the grid section can be easily curved and shaped, with the armoring elements IE only tied together by the flexible network l1. Another practice is to lay the grid section in the stiif cement, with the gates 25 intact, and to then pound the grid section into the desired curvature with a hammer and block of wood, the gates being broken where the angle of curvature exceeds the bending modulus of the gate metal. The grid section retains this hammered shape or curvature by the engagement of the network and armoring units in the stiff cement, while the grid is being filled with the grouting and is being troweled. If it is desired to eliminate the gates 25 entirely from the grid section such may be accomplished by providing separate pouring holes for each armoring element 16 in the mold, resulting in a grid structure substantially as shown in Figure 3.

In trimming to a wall line or around a column or other projection in the floor the grid section can be easily out down in size or notched out in shape by merely breaking out the necessary gates 25 (where such are present in the grid section) and cutting away the flexible network H with ordinary wire cutters or tin shears. A single grid section may even be made to surround a pipe or other like projection by merely cutting out the interfering armoring element it from the central portion of the section and cutting a slot or notch from the margin of the section down through the network to the central opening from which said armoring element was removed, thereby enabling the grid section to be folded around the pipe in laying.

The embodiment of my invention employing a flexible network composed of sheet metal, wires or light bars, to which the armoring elements 16 are secured, possesses numerous advantages and is the preferred construction. This is particularly true when the armoring elements I6 are composed of cast iron. However, I consider it to be within the broad purview of my invention to construct the grid sections wherein all of the armoring elements H5 would be interconnected by thin metallic gates 25 extending between each and every armoring element of the section, and having no network composed of sheet metal, wires or like bars. In such embodiment, the interconnecting casting gates 25 would be of sufiiciently small sectional thickness that they could be bent readily in shaping the grid section to different slopes and curvatures of the floor surface, and that could be cut readily in trimming the section to a wall line or around a floor projection. Figure 2 illustrates gates 25 approximately of this proportion. Such embodiment would preferably be formed of cast steel, although other metals which might be used are Monel metal or some of the nickle iron alloys like Allegheny metal, or some of the non-ferrous metals such as brass, aluminum, zinc etc.

In my improved type of grid, anchorage in the cement or other plastic material of the floor is greatly enhanced by the large area of side wall surface on each armoring element l6 and by the tapered slope 26 of these side wall surfaces. The flexible network I 1 and the gates 25 also increase the area of bonding, and, in addition, serve as reenforcement for the concrete.

Figures 12 and 13 illustrate another embodiment wherein the flexible network I! is disposed in, or extends into, another plane from the plane of the cast armoring element l6. In this construction the network, which may be composed of wire or of flexible fiat metallic strips, is bent so that those portions of each strand or strip of network between adjacent armoring elements I6 are bent downwardly in U-shaped form, as indicated at IT in Figure 13. These downwardly extending U-shaped bends are also formed in the strands or strips of the network extending at right angles to Figure 13. This network can be cast within the general body portions of the armoring element I6, or they may be cast within downwardly extending bosses l6" which are cast on the undersides of the armoring elements, in either case the casting of the armoring elements on the network being performed substantially as described of the preceding embodiments. In this construction, no portion of the network is near the surface of the floor between the armoring elements and hence a considerable depth of wear is afforded before the network is exposed. A network so constructed constitutes a temporarysupport for the armoring element While pouring the cement into the open spaces of the grid. Such type of network serves as a slab reinforcing means and can be constructed to reach down to the tension side of the slab, in which arrangement the grid structure would serve the very advantageous combination of an armored wearing surface and reinforcing network. This network would preferably have the same previously described attribute of flexibility for shaping 'to curved floor surfaces, and of convenience'of cutting to marginal lines and around floor obstructions. The bottom portions of the U-shaped bends can be readily spiked or stapled to existing wood floors or wood bridge decks, preparatory to filling. This is also true of the previously described embodiments of Figures 1 to 11 wherein the flexible network is disposed adjacent to the bottom plane of the armoring units IS in which plane the flexible network can be readily spiked or stapled to wood floors or wood bridge decks when the composite floor is to be laid on such a surface.

Each of the previously described embodiments of metallic grid structures possesses the very important advantage of avoiding the difliculties and losses arising from warpage such as is frequently encountered in the old rigid cast metal grid structures. In the old rigid type of cast grid of relatively large area the warpage of the casting meant high losses in the foundry and imperfectly finished surfaces when laid. The tendency to warp increases with increased surface area and also with diminished depth of section. Warpage means nothing in the present construction because it is a simple matter to bend the grid struc ture and' thus straighten out the grid. The in-- herent flexibility of the present grid structure also enables the matching or overlapping of the contiguous portions of adjacent sections to be easily performed.

The embodiments previously described are pref erable, but, if desired, the elements IE5 in any of these embodiments might be constructed of rubber, preferably comprising a large proportion of fabric or other body forming material, thereby producing a non-slipping grid surface; or they might be constructed of a hard cement or vitrified ceramic composition orothersuitable composition. Such materials might be cast in interlocking engagement with the flexible network or they might be pressed into interlocking engagement therewith.

In Figures i i and 15 each element I6 consists of a top section 55a and a bottom section Nib. The flexible network is laid. in between these sections and the latter are then rigidly secured to each other and to the network by extending rivets 4! between the two component sections and through the network. The network may consist of wire mesh, perforated metallic plates or light strips or bars.

In Figures 16 and 17 the elements 46 are welded to the network. This might be accomplished by spot welding or any other desired welding method, although I find it less expensive and pref erable to tack weld the elements 16 to the network, as indicated by the tack welding points 44. Either of the previously describe-d forms of flexible network can be used, but I find that the welding operation is simplified when using open work or perforated sheet metal plates.

It will be noted that in each of the previously described embodiments the armoring elements it are so formed and are so arranged on the flexible network of the grid section that there is no discontinuity of metallic or armored wearing surface in any direction of wheel travel on the grid section. That is to say, considering any direction or line of wheel travel over the section, there is always overlap between portions of any two adjacent armoring elements, i. e., some portion of any one armoring element projects into the perimetrical outline or confines of the next armoring element so that a rolling wheel of any substantial width always has some part of its tread resting on an armoring element. This prevents the condition arising wherein the cementitious material, by reason of more rapid wear than the armoring elements, gradually becomes worn down into continuous grooves or corrugations extending across the width or length of the grid section. Such condition arising usually causes severe shocks to be set up in the action of a heavy wheeled load rolling across these grooves or corrugations, thereby intensifying the rapidity with which the cementitious material is broken up and pounded out of the spaces between the armoring elements. In addition to the fact that my improved construction establishes overlap in all directions for preventing the development of this grooved or corrugated condition, it should be noted that this overlap arrangement does not result in narrow, slender bodies of concrete between the sections nor in small isolated bodies of concrete, but to the contrary, the concrete extends substantially from edge to edge of the grid section in continuous relatively wide bodies which have maximum strength in compression, shear and tension. Furthermore, in the constructions illustrated in Figures 1, 5, 11, 12, 14 and 16, the entire concrete wearing surface is monolithic in that there is no isolation of concrete bodies, but, instead, every unit of concrete surface is an integral part of every other unit. This strengthens the wearing surface materially because the vibration and pressure of heavy loads tend to loosen relatively small isolated bodies of concrete and to pound them out of their set positions in the floor or decking.

While I have described what I regard to be the preferred embodiment of my invention and the preferred method of carrying the same into effect, it will be understood that such is merely exemplary and that numerous modifications and rearrangements and different practices may be followed without departing from the essence of the invention.

I claim:-

1. An armored floor comprising a plurality of grid structures laid end to end and side by side in the floor, each of said grid structures comprising a plurality of cast iron armoring elements, the upper surfaces of which are exposed at the surface of the finished floor, a flexible metallic network constructed of flexible connecting members extending in different directions in said grid structure substantially from edge to edge thereof, said flexible connecting members being cast into said cast iron armoring elements and interconnecting the lower portions of said elements below the surface of the finished floor, the flexibility of said network enabling the grid structure to be shaped longitudinally and transversely and to be readily cut for trimming the grid structure to predetermined lines, and a body of cement filling the spaces between said armoring elements, the armoring elements of each grid structure being so formed and being so arranged on the flexible network of said grid structure that there is substantially no discontinuity of metallic wearing surface in any direction of wheel travel on said grid structure.

2. An armored floor comprising a plurality of grid structures laid end to end and side by side in the floor, each of said. grid structures comprising a plurality of spaced cast iron armoring elements, the upper surfaces of which are exposed at the surface of the finished floor, a flexible metallic network constructed of a series of wires extending longitudinally and transversely of the individual grid structure substantially from edge to edge thereof, said wires being cast into said cast iron armoring elements and flexibly interconnecting the lower portions of said elements below the surface of the finished floor and said armoring elements being substantially isolated from one another in their mounting on said network, whereby the flexibility of said network enables the grid struoture to be shaped longitudinally and transversely and to be readily cut for trimming the grid section to predetermined lines, and concrete filling the spaces between said armoring elements and establishing a monolithic body at the surface of the floor extending over the entire area of the grid structure between the spaced armoring elements.

3. An armored floor comprising a plurality of grid structures laid end to end and side by side in the floor, each of said grid structures comprising a plurality of spaced cast iron armoring elements, the upper surfaces of which are exposed at the surface of the finished floor, a flexible metallic network constructed of a series of wires extending longitudinally and transversely of the individual grid structure substantially from edge to edge thereof, said wires being cast into said cast iron armoring elements and flexibly interconnecting the lower portions of said elements below the surface of the finished floor and said armoring elements being substantially isolated face in any direction of wheel travel on said grid structure, and concrete filling the spaces between said armoring elements and establishing a monolithic body at the surface of the floor extending over the entire area of the grid structure between the spaced armoring elements.

4. An armored floor comprising a plurality of grid structures laid end to end and side by side in the floor, each of said grid structures comprising a pliable metallic network comprising longitudinal portions extending substantially from edge to edge of said grid structure and transverse portions extending substantially from edge to edge of said grid structure, a plurality of armoring elements, said armoring elements and the longitudinal and transverse portions of said network being integrally joined together in laterally fixedrelation, the upper surfaces of said armoring elements lying above the plane of said network and adapted to be exposed at the surface of the finished fioor, and a body of cement filling the spaces between said armoring elements, said armoring elements being substantially isolated from one another whereby the cement establishes a substantially monolithic body at the surface of the floor, the pliability of said network and the isolation of said armoring elements enabling said grid structure to be shaped to changes of direction of the floor surface both longitudinally and transversely and inherently to maintain said surface adjustments.

5. An armored floor comprising a plurality of grid structures laid end to end or side by side in the fioor, each of said grid structures comprising a plurality of spaced,relatively rigid, armoring elements, the upper surfaces of which are exposed at the surface of the finished floor, a plurality of flexible wires in each individual grid structure extending between said armoring elements and disposed below the surface of the finished floor, said wires having permanent attachment to said armoring elements and constituting a pliable metallic network permanently holding said armoring elements in proper spaced relation inthe individual grid structures, whereby each grid structure can be handled as a complete unit in transporting and laying the grid structures, said armoring elements being substantially isolated from one another in the finished floor, and a body of cement filling the spaces between said armoring elements, the pliability of said network and the isolation of said armoring elements enabling the individual grid structures to be shaped to changes of direction of the floor surface both longitudinally and transversely and inherently to maintain said surface adjustments in the laying of the floor.

6. An armored floor comprising a plurality of grid structures laid end to end or side by side in the floor, each of said grid structures comprising a plurality of spaced metallic armoring elements, the upper surfaces of which are exposed at the surface of the finished floor and the lower surfaces of which rest on the sub-structure on which the floor is laid, a plurality of flexible wires in each individual grid structure extending between said armoring elements and disposed between the planes of the upper and lower surfaces of said armoring elements, said wires being integrally joined to said armoring elements and constituting a pliable metallic network permanently holding said armoring elements in proper spaced relation in the individual grid structures, whereby each grid structure can be handled as a complete unit in transporting and laying the grid structures, and a body of cement filling the spaces between said armoring elements, said armoring elements being completely isolated from one another whereby the cement between said armoring elements establishes a substantially monolithic body at the surface of the floor, the pliability of said network and the isolation of said armoring elements enabling the individual grid structures to be shaped to changes of direction of the floor surface both longitudinally and transversely and inherently to maintain said surface adjustments in the laying of the floor.

7. An armored floor comprising a plurality of grid structures laid end to end and side by side in the floor, each of said grid structures comprising a plurality of rigid spaced armoring elements, the upper surfaces of which are exposed at the surface of the finished floor, a metallic network disposed below the surface of the finished fioor and beneath said armoring elements, said network having rigid attachment to said armoring elements and constituting a pliable means permanently holding said armoring elements in proper spaced relation in the individual grid structures, said armoring elements being substantially isolated from one another in the finished floor, and a body of cement filling the spaces between said armoring elements and holding said network in fixed position to anchor said elements, said network inherently serving to maintain surface adjustment of said grid structures in the laying of the fioor.

8. An armored floor comprising a plurality of grid structures laid end to end and side by side in the floor, each of said grid structures comprising a plurality of rigid spaced armoring elements, the upper surfaces of which are exposed at the surface of the finished floor and the lower surfaces of which project into the material forming the floor, said armoring elements being substantially isolated from one another in the finished floor, means for joining said grid structures together as a substantially rigid unit including a wire-like network extending below the plane of the grid structures and serving to increase the strength of the floor slab, and. a body of cement filling the spaces between the armoring elements holding said network in fixed position to prevent relative movement of said grid structures, said network being pliable to allow said grid structures to assume the curvature of the floor surface during the laying of the floor.

9. An armored floor comprising a plurality of grid structures laid end to end and side by side in the floor, each of said grid structures comprising a plurality of rigid spaced armoring elements, the upper surfaces of which are exposed at the surface of the finished floor and the lower surfaces of which project into the material forming the floor, said armoring elements being substantially isolated from one another in the finished floor, means for joining said grid structures together as a substantially rigid unit including a wire-like network, and a body of cement filling the spaces between the armoring elements holding said network in fixed position to prevent relative movement of said grid structures, said network being pliable to allow said grid structures to assume the curvature of the floor surface during the laying of the floor.

16. An armored floor comprising a plurality of grid structures laid end to end and side by side in the floor, each of said grid structures comprising a plurality of rigid spaced armoring elements, the upper surfaces of which are exposed at the surface of the finished floor and the lower surfaces of which project into the material forming the floor, said armoring elements being substantially isolated from one another in the finished floor, means disposed in the plane of said grid structures and constituting a pliable network for tying said armoring elements in rigid spaced relationship and having overlapping engagement between said grid structures for connecting said grid structures together as a rigid unit in the finished floor, and a body of floor material filling the spaces between the armoring elements and serving to key said network in fixed position tomaintain said grid structures in proper adjustment conforming to the curvature of the fioor surface during the laying of the floor.

11. An armored floor comprising a plurality of grid structures laid end to end and side by side in the floor, each of said grid structures comprising a plurality of rigid spaced armoring elements, the upper surfaces of which are exposed at the surface of the finished floor and the lower surfaces of which project into the material forming the floor, said armoring elements being substantially isolated from one another in the finished floor, means disposed below the plane of said grid structures in the fioor increasing the section modulus of the floor slab and constituting a pliable network connecting the grid structures together, and a body of cementitious material filling the spaces between said armoring elements to establish a sub-monolithic body at the surface of the floor and serving to key said network in position to provide a rigid supporting connection preventing relative movement of said grid structures when the floor is formed.

LON SLOAN.