US2979801A

US2979801A - Method of making reinforced cast shapes

Info

Publication number: US2979801A
Application number: US760381A
Authority: US
Inventors: Richard C Gasmire
Original assignee: Owens Illinois Glass Co
Current assignee: OI Glass Inc
Priority date: 1958-09-11
Filing date: 1958-09-11
Publication date: 1961-04-18
Anticipated expiration: 1978-04-18

Description

April 18, 1961 c, GASMlRE 2,979,801

METHOD OF MAKING REINFORCED CAST SHAPES Filed Sept. 11, 1958 2 Sheets-Sheet 1 INVENTOR.

April 18, 1961 c, GA$M|RE 2,979,801

METHOD OF MAKING REINFORCED CAST SHAPES Filed Sept. 11, 1958 2 Sheets-Sheet 2 INV EN TOR.

United States Patent METHOD OF MAKING REINFORCED CAST SHAPES Richard C. Gasmire, Toledo, Ohio, assignor to Owenslllinois Glass Company, a corporation of Ohio Filed Sept. 11,1958, Ser. No. 760,381 r 1 Claim. 01. 25-154 The present invention relates to a method of making reinforced cast shapes. More particularly, this invention proposes a method of inserting reinforcing grids into uncured cementitious bodies of the cast calcium silicate (commonly known as cellular concrete).

Cellular concrete bodies are commercially manufactured as unit slabs having integral metallic reinforcing grids. A typical commercial casting mix is a slurry of cement, lime, and silicate to which a preformed foam is added prior to the pouring of the casting mix into a multiple mold. This mold is preferably of unit length and width dimensions but of multiple slab thickness, the mold contents being removed and subdivided into unit slabs after pre-curing at ambient pressure and temperature conditions to a self-sustaining condition. The pre-cured cast block, after severing into unit slabs, is generally autoclaved for a period of about ten hours at a steam pressure of about 150 lbs. per square inch to'form a finished product having a density of about 30 to 40 lbs. per cubic foot.

The present invention proposes the insertion of spaced reinforcing grids into the cast multi-slab block at unitslab spaced intervals after the slurry or casting mix has been poured into the mold, but prior to the pre-curing of the casting mix. Since the casting mix is quite fluid when poured into the mold (to promote fluid handling of the mix and to insure complete filling of the mold), some means must be provided for holding the grids in position within the casting Inasmuch as the multi-slab block is severed lengthwise into several slabs, the reinforcing grids must be quite accurately positioned and retained in spaced parallel relation. i

In accordance with the present invention, each reinforcing grid is secured to a plurality of longitudinally spaced hangers which projectver'tically into the mold. These hangers are-preferably each in the form of a vertically extending rod secured to the'reinforcing grid by a frangible connection,-'as by a tack weld, and provided with an abutment for contacting -a positioning means superimposed over, but lying outside the confines of, the casting mold. Since the hanger rodsare cylindrical in shape and are only lightly secured to the reinforcing grids, the hanger 'rods can be rotated to break their connection with the reinforcing grid, and then the'hanger'rodscan be retracted vertically out of the pre-set casting mixafter the casting mix has solidified sufliciently to retain the inforced cast shapes by the insertion of a reinforcing mesh.

into an uncured casting slurry, supporting the mesh in position within the slurry until the slurry has solidified sufficiently to retain the mesh in position, and then retracting the mesh support from the slurry.

It is a further object of this invention to provide a method for inserting areinforcing mesh into an uncured cementitious body which is subsequently cured to a selfsustaining state by vertically suspending the mesh from an attached suspending means in the uncured body, at least partially curing the body, detaching the suspending means from the mesh, and removing the mesh suspending means.

Other objects and advantages of the invention will appear from the following detailed description taken in conjunction with the annexed drawings, in which:

On the drawings: I

Figure l is an elevational perspective view of a cast slab having an integrally cast reinforcing mesh, the slab being made in accordance with the methodand apparatus of the present invention;

Figure 2 is a sectional view taken along of Figure l;

Figure 3 is a plan view of an apparatus of the present invention;

Figure 4 is a sectional view taken along the plane 44 of Figure 3; and

Figure 5 is a sectional view taken along the plane 55 of Figure 3.

As shown on the drawings:

In Figs. 1 and 2, reference numeral 10 refers generally to a cast calcium silicate slab having an integrally cast metallic reinforcing grid 11 disposed interiorly thereof. It will be noted that the slab 10 presents continuous exthe plane 22 terior surfaces and that the reinforcing mesh 11 is disposed wholly interiorly thereof. The mesh 11 comprises horizontal rods 12 and vertical rods 13 welded or otherwise secured to one another at their points of intersection and the upper and lower marginal extremities of the grid 11 are deflected laterally and vertically to provide offset end portions 14 (best shown in Figure 2) which aid in securing the mesh in position within the slab.

As best illustrated in Figures 3, 4 and 5, the 'slab 10 is made in a mold 20 which comprises a plane mold bottom 21 having superimposed thereon side walls 22'.and

end walls 23, the walls being secured to one another and to the bottom wall by suitable means, such as swing bolts 24. i

, When the

mold walls

21, 22 and 23 are assembled as illustrated in Figures 3, 4 and 5, the walls define an interior molding space 25 which is adapted to receive a casting mix. This casting mix ,compriseswater, cementitious ingredients, pozzolans, accelerators, and foamor foam-forming ingredients. I

The cementitious ingredients are preferably cement of the Portland type, either normal or of the high early strength type, and lime, preferably quick lime, although a high calcium hydrate of lime may be utilized; Any pozzolanic material may be utilized, a pozzolan being defined as a finely divided material rich in silica or alumina which, while not necessarily cementitious in itself, will react at ordinary temperatures with hydrated lime in the presence of water to form insoluble cementitious products. The preferred pozzolan is silica flour, although groundsilica sand, burned oil-shell, fly ash, ground brick or tile, volcanic ash, granulated slag, diatomaceous earth,

. pomace dust, glass grinding waste, or other suitable poz zolans may be utilized.

'Preferably, a pre-formed foam is utilized, the foam resin soap, saponin, alkylatednapthalene, sulphonates,

neutralized synthetic resins or hydrolyzed protein, or commercial foaming liquids, such as National Cote HT-l manufactured by National Foam Systems, Inc., of Westchester, Pennsylvania. 4 Toform a typical casting slurry for use in forming foamconcrete, the following composition may be utilized:

j V Percent HighEarly cement 28.6 Silica flour 66.5 Quick lime 4.9

foot; A commercial foaming agent sold under the trade name National Foam Liquid manufactured by National Foam Systems, Inc., of Westchester, Pennsylvania, and consisting of a 3% solution of the foaming agent and water and suificient air to form a consistent air-stable foam as utilized to an extent consisting of 0.016 gallon of foaming agent per 100 pounds of slurry.

allowed to air cure.

The slurry is introduced into the mold space 25 and As introduced into the space 25, the slurry is readily flowable and is obviously incapable of supporting the vertically disposed wire reinforcing mesh 11 therein.

Also, it will be noted from Figures and 5, the space Y 25 is of multi-slab dimensions, i.e., the height of the mold space is substantially equal to the Width of the individual slabs, and the length of the mold space is substantially equal to the length of the individual slabs. However, the mold space is of multiple slab thickness. Because of the dimensions of the mold space and the fluidity of the slurry introduced thereinto, it is necessary to suspend a plurality of the wire meshes 11 within the slurry-mesh filled space. a

As best'illustrated in Figures 4 and 5, there is secured to each mesh' 11 a vertically extending support rod 39. More'particularly, from Figure it will be seen that each of these supporting rods 30 is secured to the associated mesh 11 adjacent the upper and lower extremities of the I mesh, for example as at 31. Preferably, the rods 39 are secured to the mesh by tack welding or otherwise lightly or frangibly securing the rod against the back face of the reinforcing mesh, i.e.,

against that face away from the bent ends 14 thereof.

Further, 'it will be noted that each of the rods has secured thereto .a locating abutment 32 adjacent the upper extremities of 'thefrods and outside the confines of the mold' space 25. This abutment 32 preferably is an enlarged washer which issecurely weldedor otherwise fastened to the rod 30. Superimposed over the mold space '25 are a pair of 'longitudinally spaced locating jigs 46,

each of these jigs comprising upper and lower transversely extending

support plates

41 and 42 secured together'in vertically spaced relationby spacers 43, and

. 4 slidably receive therein'the upper extremities of the rods projecting above the mold space 25. It will be noted that the notches of both of the jigs open in the same direction and it will be appreciated that these notches make possible the ready assembly of the jigs 40 and rods 30 as illustrated in Figures 35.

The manipulative steps .involved in j practicing the method of the present invention include securing of the support rods 30 to the reinforcing mesh 11. The mesh 1 together with the lower extremities of the reinforcing rods are submerged within the body of slurry filling the mold space 25. The jigs 40 are now superimposed over the mold space, contacting the side walls 22 .of the mold and the jigs are slid into position beneaththe abutments or washers 32. Next, the mesh is adjusted longitudinally 7 within the mold space to bring the individual grids into accurate transverse alignment. The transverse spacing of the notches 44in the plates 41 and 42'insures the accurate transverse'spacing of the grids adjacent thereof.

Next the slurry is pre-cured preferably at ambient temperatures and pressures with the mesh grids L1 and the suspension rods 30 in situ. After the slurry has been pre-cured and sufficiently solidified to retain the mesh grids 11 in position, the suspension rods 30 are rotated slightly to break the tack welds '31, thereby separating the suspension rods from the associated grids. The suspension rods are'then removed vertically from the body of the at least partially solidified slurry, and the mesh grids are isolated within the solidified slurryfilling the mold space;

After removal of suspension rods 30, the slurry is further pre-cured, necessary, to a completely selfsustaining state and the mold side and end-

walls

22 and 23 are removed from the precured block of multi-slab thickness The cast block is then severed longitudinally along unit slab thickness planes as, for example, de-

scribed and claimed in United States Patent No.

within saidslurry, immersing said grid into the slurry and supporting the projecting portions of said suspension rods "to support said grid at the desired locationwithin said slurry, partially curing the slurry to aniextent suflicientto support said grid,,rota-ting each suspension rod relative tothe grid about its vertical axis to rupture the tack welds, and withdrawing each suspension rod from the slurry inn directionalongits vertical axis.

References Cited in the file of this .patent N f FOREIGN PATENTS Belgium Sept. 15, 1953 839,92? Germany'i May 26, 1952 291,838 Great Britain June 5, 1928