US996288A - Reinforce concrete. - Google Patents

Description

T. H. SKINNER.

REINFOR 121 1101111011 FILED 2211.24, 1908. RENEWED MAY 16, 1911.

GED CONCRETE.

Patented June 27, 1911 THEODORE H. SKIN-NEE, OF ONEIDA, NEW YORK, ASSIGNOR TO ONEIDA COMMUNITY LIMITED,OF ONEIDA, NEW YORK, A CORPORATION OF NEW YORK.

REINFORCED CONCRETE.

Specification of Letters Patent. Patented J une 2'7, 1911.

Application filed February 24, 1908, Serial No. 411440; Renewed May 16, 1911. Serial No. 627,511.

'ments in reinforced concrete for walls,

floors, ceilingsan d other fiatpr slab struc I tures where it is desired to provide reinforcing meansv to compensate for tensile weakness of'the concrete and to afford increased resistance against bending, buckling and other'tensile or torsional strains to which the concrete mayv be subjected.

I have discovered, in the use of the .,Kahn bars and other continuous unbroken metallic rods which are usually em bedded in concrete reinforcements, that the expansion and contraction and stretching of the rods due to tensile strains or temperature changes may loosen the adhesive bond between said reinforcement and said concrete so that. in time the reinforcing may have more or less play in such concrete; and further that vibration of the floor, ceiling or wall in which these rods are placed causes similar movement of the same in the concrete, thereby destroying said adhesive bond,

rupturing the concrete adjacent thereto and forming appreciable openings through which the rods may slip, thereby destroying the utility of the combination or at least reducing its efiiciency'r and rendering the composite structure unable to carry such loads and strains as it was theoretically calculated to sustain. On the other hand, I

have discovered and proven by many prac- 4 to minimum because of the fact that each "link is independent of the other and its ex:

pansion and contractionare not transmitted to those adjacent, and is, therefore, not cumulative and does not disrupt the bond between it and the concrete; the same advantages are also evident when concrete.

structures reinforced in the chains are subjected to vibration, and its temperature is more easily held to that of the concrete in which it is embedded. Furthermore what little if any expansion does occur in the individual links could not be transmitted to the adjacent link because of the loose 'connection between them "while on the other hand high compressionresistance of the concrete filling through the openings in thelf links prevents stretching of said links on der tensile strains which compensatesin aft measure for the tensile weakness ofthe concrete so that when the chains are incorporated in the concrete,.t-l1e links retain their original position and thereby prevents loosening of the skin adhesion between the concrete and surface area of the reinforcement.

Therobject, therefore, of my present inv vention is to provide simple and practicalmeans whereby these chains may be economy cally employed. as reinforcements for extensive areas of concrete such as floors, ceil- A further ,object is to provide each spacmg member with one or more openings between the adjacent chains through which thelconcrete may be worked .ori filled and ,knit toestablish as many anchorages in the concrete for the purpose of resisting tensile strains or stretching of such spacing members under the various strains to which they may be subjected and by. means ofithese plural anchorages preventing'movcment of the spacing members relatively to the concrete so that the cementitious or skin adhesion between the metal and concrete will I be more permanent. It will be seen, therefore, that the main purpose of using the open link chains and perforated or apertured spacing members is to establish a more view of the reinforcement and Figs. 3 and.

a; are sectional views ofa modified form of spacing member for the open link chains.

in order to demonstrate the practicability of my invention, I have shown a flat body ---l of concrete in which is incorporated my improved reinforcement consisting of a series of parallel open link chains 2- which are spaced some distance apart and are held in this position by transverse spacing members -3--.

The'links of the chain are permanently but flexibly connected at their ends one with the other but the intermediate portions are formed with openings through which the concrete, into which the reinforcements ar embedded, is worked and thoroughly knit until the entire. intervening spaces between the sides and ends of the links are filled so' that each link is individually anchored in the concrete against relative movementand at the same time the filling of concrete through the. openings in the links atfordsa high con'ipression resistance a ainststretching of the chain, said open llIlKS also affording alarge surface area for skin adhesion to--'eeinentitious parts of the concrete and owing to the facttha-t expansion and contract-ionof each link are practically negligibie this skin adhesion remains substantially intact and permanent.

is shown inj-Figs. 1 and 2, each stay, tie piece'orspacing member 3 consists of a pair of wires which'arebrought together against opposite sides of the entire series of chains and the portions between the chains are twisted or turnedaround forming twists '--:t close to but at opposite sides of each chain, thereby leaving open loops -5, the opposite sides of which embrace and retain the adjacent portion of the link in fixed relation to the tie piece. The opposite wires of each tie piece between the chains are left spaced apart forming an open loop -7-. through which the concrete may be worked and knitted together to" anchor and retain the tielp, s against relative endwise nove merit int c concrete and at thesame time. the cone 3 filling through the loops -7 affords a high compression resistance against ii'ng of these portions of the tie pieces under tensile strains to which they may-be subjected. In some instances I may prefer I to use sheet metal tie pieces or spacing members -lO-, Fig. 3, in which case, portions of these sheet metal tie pieces are out and pressed laterally to form tongues ---ll" scription that the essential feature of my in vention lies in embodying a series of chains in concrete and tying them together by spacing members which hold such chains a fixed distance apart, the chains having open links through which the concrete is Worked and knitted so that each link is anchored individually in the concrete and the concrete filling through said links not only affords a high compression resistance of' the links under tensile-strains but also affords a large area for skin adhesion of the cement and owing to the fact that each link is anchored individually, the liability of loosening this skin adhesion by expansion and contraction is reduced to a minimum thereby preserving the tie between the concrete and metalwhich enables the metal reinforcement to bettercompensate forthe tensile weakness of the concrete The same argument applies to providing spacing members or tie pieces with openings or loops through which the concrete may be worked so that when the metal reinforcements is incorporated in the concrete it retains its original position under the various strains to which it is subjected. Furthermore it is self evident that as the bond between the concrete and steel is only that givenby' shrinking of'the-concrete in settling, the'reb icausing skin or surface or frictional adheson between the surface of the steel and the concrete coming into contact therewith, if the surface of a unit of steelreinforcing can be increased without,

diminishing the tensile strength of said unit,

a larger adhesive bond would result and greater structural strength be attained by the combination, and that by drawing the unit metal into wire and'then fashioning the same into open. links as shown, a deformation of the metal is obtained giving vastly larger surface for the adherence of the concrete than would be obtained with the same unit of metal in bar form. Furthermore the open link form by providing spaces for concrete to knit or mesh through presents absolute buttressing or anchoring for each link in the concrete, in addition to skin or su-r-' face adherence, thus affording an additional source of strength in combination and thereby enlargingthe circumferential area of the cylinder of-concrete which must be sheared out in order to effect a separation of all the combined elements or cause rupture in the structure; and ncrete when so knitted or meshed through such open links, and com- 'bined therewith forms studs or struts within the same preventing deformation when stressed, and consequent elongation. This maintenance of links in their manufactured form enables them tb withstand tel;- sile stresses equal to any, the ,unit metal in bars would withstand, and, therefore, by first increasing the surface adherence as above mentioned, and second by perfect me chanical bond, I am able to produce when using open links chains embedded in concrete, greater strength in the combination, with the" same weight of metalor this granted as a corollary equal strength with a less weightof metal, thus effecting economy in construc'tion.

In Fig. 4 I have shown a further modified form of reinforcement in which the stay bars or rods are passed through the links of the horizontal chains and are provided with suitable retaining means as the tongue 20 for engaging the link and locking the chains against relative movement on the tie rods or spacing members.

hat I claim is:

1. Reinforced concrete having incorporated therein a series of open link chains. and rigid spacing members holding said chains a fixed distance apart. v

2. Reinforced concrete having embedded therein a series of open link chains and rigid transverse spacing members interlocked with the chains and holding them a fixed distance apart, the concrete being worked and knitted through the openings in the links to anchor each link separately and prevent stretching of such links.

3. Reinforced concrete having incorporated therein a series of open link chains, and rigid spacing members holding said chains a-fixed distance apart, and provided with openings through which the concrete is worked and knit.

l. Reinforced concrete having incorpo rated therein a series of open link chains, and rigid spacing members holding said chains a fixed distance apart, and provided with openings between the chains, the openings in the links and spacing members being filled with concrete which is knitted therethrough to anchor the reinforcement at as many points as there are openings in the reinforcement.

5. Reinforced concrete having embedded herein a plurality of open link chains, and rigid spacing members embracing the chains and holding them apart.

ti. Reinforced concrete having embedded therein a plurality of open link chains, and rigid spacing wires embracing the chains and twisted at opposite sides thereof to hold such chains a fixed distance apart.

7. Reinforced concrete having embedded therein a plurality of open link chains, and rigid spacing wires embracing the chains and twisted at opposite sides thereof to hold such chains a fixed distance apart, the portions of the spacing members, between the chains being formed with open loops through which the concrete is worked and knitted.

8. A reinforce section for concrete structures consisting of a plurality of chains and a plurality of rods disposed substantially at right a'iigles to the chains and firmly engaging links in alinement to hold the chains against lateral movement relatively to each other and the rods during progressive building.

In witness whereof I have hereunto set my hand on'this 17th day of February, 1908.

THEODORE H. SKINNER.

Witnesses:

CLAUDE E. MARBLE, G. WAYLANI) SMITH.

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