US1726031A - Precast roof slab - Google Patents

Description

yAug. 27, 1929. Q LATHROP 1,726,031

PRECAST ROOF SLAB Filed Feb. 7, 1924 l'g, f.

Patented ug. 27, 1929.

JAY LATHROP, 0F CINCINNATI, OHIO.

4rREcAsir nooFspAB.

Application l'ed February 7, y1924; Y Serial` No. 691,092.

My invention relates to slabs which are cast of gypsum or cement composition 'for use in laying roofs, floors, partitions, side walls, sidewalks, driveways, and like structures, particularly roofs and lloors. S'uc'h pre-cast slabs are used in place of monolithic construction, formed on the job by erecting forms, and pouring the plaster cement, gypsum or the like.

The practice at the present time 1n precast blocks for roofs and floors, is to provide a metal reinforced plaster block with unprotected edges. This not only results 1n the block chipping while being transported, but also falls short of providing ample strength, so that only comparatively small sizes are practical to the end that the structure on which the blocks are laid, will take the large loads, and so that the units themselves will possess sufficient strength of themselves due to the short distance. to points of support from any point of application of load to the individual block.

It is my object to provide a block which can be used in any transportable and manipulatable size, in which the edges are protected and proper anchorage provided for reinforcing rods orV mesh.

This object and other advantages to be noted I accomplish by that certain construction and arrangement of parts to be hereinafter more specifically pointed out and claimed.

In the drawings:

Figure l is a section taken along one of the I-beams, forming the framework'of a building structure.

Figure 2 is a perspective of one of the pre-cast slabs.

Figure 3 is a perspective View of the metallic parts of one form of the pre-cast slab.

In making up the slab, I first make a form, and place therein along the sides thereof, a pair 0f rails 1, or they may be I-beams, channels or other accepted forms of metallic building material. I prefer rails because of their rounded top surfaces, and the fact that their bases extend beyond the vertical planes of the outer edges 0f the tops, thereby permitting me to abut two blocks against each v other, with provision for a form between the two blocks into which plaster may be poured.

I also place reinforcing rods, or mesh into the form, and preferably tie them or it, into the rails. Thus in the example shown, the

it come either flush or a desired amountv above the tops of the rails.

The block will then be ready for use when hard, and will have sides formed by exposed sides of the beams or rails 1, and eX- tending throughoutl the reinforcing rods or mesh, which not only gives strength to the plaster or cement material, but ties the rails together.

The blocks may be made of any convenient size, as the reinforcements and rails or beams may be regulated in strength to suit the given purpose and size.

In laying the blocks on a structure of beams 4L the rail portions are set onto the top of the beams, extending across the span between beams. The plaster edges of the blocks will then extend along the beams.

By butting the blocks against each other, a space is left in the preferred form, this space defined by the abutting edges of the bases of the rails, and the webs, and tops of the rails, into which spaces plaster or cement is poured as at 5. This plaster will key the blocks together against any tendency to tilt, as will be evident from examination of Figure l.

Any cracks left between the edges of the blocks where they lie along the beams can be also lilled with plaster or cement, and any desired coat applied to the whole floor, roof, or other structure that has been so built.

In shipment the rails protect the blocks from chipping, and in use the rails transmit the load to the supporting structure. A maximum economy in construction cost and service, together with protection during shipping at crucial points, is provided by my invention.

I Wish it understood that I have illustrated but one acceptable form of my invention, and that I wish to state in the claims that follow the points therein which I consider to be invention.

Having thus described my invention, what I claim as new and desire to secure by Letmeans securing the bars to the metallicv 10 ters Patent, is pieces, said retaining means adapted to be A pre-Cast oeinentitious construction slab tightened after the cementitious material comprising a body of cementitious material, has set, and the outer sides of the metallic 5 at least one set o'l opposite edges of said maypieces of irregular shape y:for firmly holding terial formed Of'metallic pieces, reinforcing Cementitious material disposed between simbars extending through the ceinentitious malarly cast slabs.

terial7 and holes in the metallic pieces through which the bars extend, retaining JAY C. LATHROP.

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