GB2130631A - Method and apparatus for supporting a vertical cylinder of wet cement surrounding a vertical pipe passing through a horizontal concrete slab - Google Patents

Abstract

A method and apparatus for supporting a vertical cylinder of wet cement surrounding a vertical pipe passing through a horizontal concrete slab in which one leg of an L-shaped piece 10a is wrapped around the vertical pipe just below the slab and the other leg of the L-shaped piece is slit to form a a series of slats 16 which radiate horizontally around the pipe. A circular sheet of moisture resistant material 12 having a hole in its center corresponding to the diameter of the pipe and slit from its center to its outer edge is slipped around the pipe just above the slats of the L-shaped piece, which is then pushed upwards on the pipe to press the sheet against the lower surface of the concrete slab. The piece and sheet are secured in position by a wire wrapped and twisted about the leg of the piece wrapped around the pipe. Wet cement can now be poured from above into the void between the pipe and the slab to be supported during its drying by the sheet and piece. The piece used is cut from an elongated strip having one leg formed into a series of parallel slats. <IMAGE>

Description

SPECIFICATION Method and apparatus for supporting a vertical cylinder of wet cement surrounding a vertical pipe passing through a horizontal concrete slab This invention relates to a method and apparatus for supportingavertical cylinderofwetcementsurrounding a vertical pipe passing through a horizontal concrete slab.

In the construction of high rise buildings, each horizontal concrete slab forming a floor contains a large numberofcylindrical holes cast into the slab to permitthe installation of vertical pipes of varying size carrying water, gas, electricity and sewage to orfrom each floor. Usually the hole is cast with a diameter abouttwo inchesormore largerthan the diameter of the pipe to permit positioning the pipe.

Afterthe pipes have been installed, and often after wall-support members have been installed around the vertical pipes, it is necessary to comply with building codes to fill in the void between each pipe and the surrounding slab with wet cement.

Upto now, to supportthe wet cement while drying, a carpenter would cut identical semi-circles along one edge of two square or rectangular blocks of plywood, the semi-circles having a diameterjust largerthan the diameter of the pipe. The two matching blocks of plywoodarethenfitted around the pipe and each block nailed to the lowerface ofthe slab. The two blocks thus form a supportforthe wet cement poured in from above to fill the void between the pipe and the slab.

However, this method ofsupportingthewetcement requires about 30 or more minutes time of a skilled carpenter and is both costly and awkward, especially when wall supporting members along the ceiling interfere with accessibility to and space for placing the plywood blocks around the pipe.

The present invention provides an improved method andapparatusforsupportingthewetcement.

As seen from one aspect, the present invention provides a method offilling with wet cement the space between a vertical pipe and a horizontal concrete slab through which the pipe extends, comprising wrapping one leg ofan L-shaped piece around the vertical pipe justbelowtheslab,theotherleg ofthe piece being slit to form a seriesofslats radiating horizontally around the pipe, slipping a circular sheet offlexible moisture resistant material aboutthe pipe just above the slats of the piece, pushing the piece upwardly on the pipe so as to press the sheet firmly againstthe lowerface of the slab, securing the sheet and piece in position, and then pouring wet cement into the space between the pipe andthe slab, which wet cement is supported while drying bythe sheet and L-shaped piece.

As seen from another aspect, the invention provides apparatusforsupporting a vertical cylinder of wet cementsurrounding a vertical pipe passing through a horizontal concrete slab, comprising an L-shaped piece having a first leg adapted to be wrapped around the vertical pipe and a second leg at 800 to the first leg slit into a series of parallel slats which, when the first leg is wrapped around a pipe, will radiate outwardly from the pipe likethe spokes of a wheel, and a circular sheetofflexible moisture resistant material having a hole in its center of the same diameter as the pipe and a slit from its centerto its outer edge.

As seen from afurtheraspect,the invention provides apparatus for use in filling the spaces between vertical pipesand horizontalslabsthrough which the pipes extend, comprising an elongated L-shaped strip of metal or plastic having one leg formed into a series of slats by slitting the leg at regularly spaced intervals at right angles to its elongated edge, each slit running from said edge to the angle between the two legs ofthe strip.

In one application ofthe invention I start witch an elongated strip of galvanized sheet metal orsuitable plastic bent into an L-shape and containing along one leg ofthe strip a series of parallel slits running from the edgeto the center of the strip and spaced 1/2 to one inch apartto form a series ofslats. The other leg ofthe strip contains a series of two short parallel slits about 3/8th of an inch apart, each pair of slits spaced about4 inches apart. Conveniently each strip should be about 36 inches long or somewhat longer.

If, for example, a supportis needed forthe void surrounding a pipe having a diameter of 2 inches, I cut offfrom the strip a piece having a length equal to the circumference ofthe pipe or about 6114 inches and wrap this piece around the pipe beneath the slab, using a piece of wire to hold the strip around the pipe.

A support for the wire is formed by bending upward one or more ofthe small tabs formed bythe short parallel slits in the leg wrapped around the pipe. By wrapping the one leg ofthe strip about the pipe, the slats ofthe other leg will spread apart likethe spokes of a wheel radiatingfromthe pipe. .

I then cut a piece oftarpaperor suitable moisture resistant plastic into a circle with a hole in its center having a diameterjust slightly largerthan the pipe and a slit from the hole to the outer edge ofthetarpaper circle. This circle is slipped around the pipe and the piece shoved upward on the pipe to pressthetarpaper circle against the lower surface ofthe concrete slab, thereby forming a secure supportforthe wet cement poured in from above to fill the void between the pipe and the slab.

The foregoing method and apparatus has been successfully used to markedly reducethetime and expense offilling the voids between vertical pipes and the concrete slabs of several high rise buildings under construction in Florida, U.S.A.

Details ofthe invention will now be described with reference to the accompanying drawings, in which: Fig. lisa perspective view of a conventional metal strip used to form a strip according to my invention; Fig. 2 isa similarviewof a strip made according to my invention; Fig. 3 is a perspective view of a piece cut from the strip shown in Fig. 2 and bentto surround a pipe together with a circular sheet to be used with the bent piece to support a column of wet cement; and Fig. 4 is a side view partially in cross section showing a vertical pipe passing through a hole in a horizontal concrete slab and a piece and circular sheet as shown in Fig. 3 mounted on said pipe and supporting a column of wetcementsurrounding the pipe.

in orderto practice my novel method offilling in the void between a vertical pipe and a surrounding horizontal slab, I first construct a novel piece of apparatus from a conventional metal or plastic strip.

Fig. 1 shows one such conventional strip 10 which is formed from a sheet of galvanized steel about 36 inches long and 5 inches wide and bent 90" along a line parallel to its longer dimension to form one leg 1 Oa with a width of 1112 inches and the other leg 10b with a width of 112 inches. Such strips in varying sizes are commonly used in the construction industry.

Fig. 2 shows strip 10 modified according to my invention. Leg 10a now contains a series of two short parallel slits about 3/8ths of an inch long and 1/4th inch apart, the pairs ofslits spaced about4 inches apart.

Each pair of slits forms a bendable tab 11 3/8th of an inch long and 1/4 inch wide as shown in Figs. 2,3 and 4.

Leg 10b of strip 10 now contains a series of parallel slits spaced about 314 inch apart running from one edge ofthis leg to the other, thus forming leg lOb into a series of 3/4 by 3112 inch slats 16 attached to each other by leg 10a.

Figs. 3 and 4 illustrate how my novel method and apparatus are used. Fig. 3 shows how a piece shown as 1 Oc cut offfrom strip 10 is bent to wrap around a vertical pipe. Fig. 3 also shows a circular sheet of moisture resistant material such as tarpaper or plastic cut into a circle with a hole in its center having a diameter just slightly largerthan the pipe which it is to surround and slitfrom its centerto its outer edge. The outer diameter of sheet 12 is preferably about two inchesgreaterthatthe hole in theslab surrounding the vertical pipe.

Fig. 4 illustrates a typical use of my method and apparatus in which a vertical pipe 13 passes through a cylindrical hole in horizontal slab 14 shown in cross section. If pipe 13 has an outside diameter of 3 inches and thus a circumference of about 9 112 inches, a piece 10c having a length about 9 inches is cutfrom strip 10.

One or more oftabs 11 in leg 1 0a are bent outwardly as best shown in Fig. 3 and then leg 1 Oa of piece 1 Oc is bent into the shape shown in Fig. 3 and wrapped around pipe 13 and held loosely aboutthe pipe by a wire 15 which is positioned by bending tab 11 upwardly aboutthe wire.

Sheet 12 is now slipped about pipe 1 3just above piece lOc and then piece lOc is pushed upwardly so that sheet 12 is firmly pressed against the lower surfaceofslab 14.

As leg 10a is bent into a circle and wrapped around a pipe, slats 16 of piece 1 Oc spread out like the spokes of a wheel radiating from the pipe to provide a firm supportforsheet 12.

With sheet 1 2firmly pressed against slab 14, wire 15 is twisted tightly about leg 1 Oa to hold piece 10c and sheet 12 in place.

Wet cement 17 can now be poured from above into the void between pipe 13andslab 14to be supported while the cement dries by sheet 12 and piece 10c in accordance with my invention.

Use of the foregoing method and apparatus results in considerable economies in the construction of high rise buildingswhich often have a thousand or more cast holes in their horizontal slabs which, in conformitywith building codes and engineering practice, must befilled. The conventional method described requires employment of a skilled carpenter and often takes 30 minutes or more. In contrast, my method and apparatus can be performed entirely by unskilled labor and usually takes onlyfive minutes per hole.

Having disclosed a preferred embodiment of my invention, those skilled in the artwill be able to modify certain aspects of my method and apparatus while still utilizing the principles of my invention and it is therefore intended that all such modifications be covered as they are embraced within the scope ofthe appended claims.

Claims (9)

1. A method offilling with wet cement the space between a vertical pipe and a horizontal concrete slab through which the pipe extends comprising wrapping one leg of an L-shaped piece around the vertical pipe just belowthe slab, the other leg of the piece being slit to form a series of slats radiating horizontallyaround the pipe, slipping a circular sheet offlexible moisture resistant material aboutthe pipe just above the slats of the piece, pushing the piece upwardly on the pipe so as to pressthesheetfirmlyagainstthelowerfaceof the slab, securing the sheet and piece in position, and then pouring wet cement into the space between the pipe and the slab, which wet cement is supported whiledryingbythesheetand L-shapedpiece.

2. The method of claim 1 wherein the L-shaped piece is secured in position by a wire twisted around the leg of the piece wrapped around the pipe.

3. Apparatus for supporting a vertical cylinder of wet cement surrounding a vertical pipe passing through a horizontal concrete slab, comprising an L-shaped piece having a first leg adapted to be wrapped around the vertical pipe and a second leg at 800 to the first leg slit into a series of parallel slats which, whenthefirst leg is wrapped around a pipe, will radiate outwardlyfrom the pipe like the spokes of a wheel, and a circularsheetofflexible moisture resistant material having a hole in its center of the same diameter as the pipe and a slit from its centerto its outer edge.

4. The apparatus of Claim 3 wherein the leg ofthe L-shaped piece to be wrapped aroundthevertical pipe contains one or more vertical tabs adapted to be bent upwardly to support a wire positioned around said leg.

5. Apparatus for use in filling the spaces between vertical pipes and horizontal slabs th rough which the pipes extend, comprising an elongated L-shaped strip of metal or plastic having one leg formed into a series of slats by slitting the leg at regularly spaced intervals at right angles to its elongated edge, each slit running from said edge to the angle between the two legs of the strip.

6. Theapparatusofclaim Swhereinthelegofthe strip which is not slit into a series of slats contains a series of short tabs, each tab formed bytwo parallel slits about one half inch long, said tabs iocated along the elongated edge of said leg and spaced aboutfour inches apart.

7. The method of claim 1, substantially as herein described.

8. The apparatus of claim 1, substantially as herein described with reference to the accompanying drawings.

9. Apparatus for use in filling the spaces between vertical pipes and horizontal slabs through which the pipes extend substantially as herein described with reference to Figure 2 of the accompanying drawings.