Field of the Invention

This invention relates to a reinforced load bearing stmcttire and morβparticulaily to a concrete load bearing structural member and/or slab with a hollow passageway extending through the structural member or slab.

modem buildings, For example, horizontal slabs of steel reinforced concretetypically between 10 and 50 centimeters thick ate frequently used to construct doors for buildings, Ia many industrial buildings, a thick concrete slab supported on a foundation is used, to construct Hie ground floor of a building.

raαefcrougϊi are also kπom For example, a U.S. PatentNo.2,938,255 discloses a m&tfcod for manufacturing beams with longitudinal passages to reduce weight A more tecent apparatus to provide hollow reinforced concrete floors is disclosed in a U.S. Patent of Breuning, No.5396,747. The Braining disclosure utilizes a planar hollow reinforced? concrete floor slab with "two dimensional structure" to obtain higher streng&and stafiEness* less volume of materials, and to obtain a balance between bending forces, shear forces and deformations and reduce the amount of cement.

A more recent concrete floor system and method of making floor components is describedin aU.S. Patent No.7,024,831 ofCϊarketal. As disclosed taan, me concrete øw concrete blocks for reducing weight and receiving a tension cable therethrough. Opposite ends ø* ifce cable are held on end plates inside recessed ends of each hollow beam. The ends of tfce beams are adapted for mounting next to the inside of the sides of a foundation walL Atop portion of each parallel beam is adaptive to receive a plurality of angularly shaped floor panels. The floor panels interlock next to the top portion of me beam. Notwithstanding the above, it ispjesentty believed that mere is a need and a potential

with the ptesent invention. There should be a potential matoforsuehstrøctuϊesbecaϊJS&ffø volume of the hollow portions can be tailored for specific appfoations by using different shapes and materials such as Styrofoam, P.V.C. pipes and steel pipes. For example, the type and shape of materials varies depending on load, span and depth of a beam. In a case whefe the beam depth is restricted it may be apprøpriate to tise steel pipes or t<*es to incjteasetite carrying capacity of a beam.

The improved reMorced load bearing struciΛires i _B accordance with the present invention can also be used with the following advantages; reducing the weight of the concrete member due to me hollow area to thereby reduce the flexural movement due to the weight This also means a reduction in cement and steel reinforcement, and increasing the moment of inertia for the member due to the added moment of inertia frame inserted pipe or tube that will lead to a reduction in deflection. The pipe or tube -will carry part of me flexural moment and this depends on the pipe material and thickness. The result of applying this approach Will provide less slag weight, less steel reinforcement and less cost Further, the system in aoc<waance with the present inventi on elhninat^meά^bean^ andmatøitpossibfeto prepare and fix the reinforcement steel on .the pipes before preparing the slabs and mis Will reduce the time and cost for workers.

BRIEF SlJMMARY OF THE INVENTION

A reinforced load bearing structure in accordance with the present invention includes an outer longitudinally extending concrete load b^ririg strucirøal member and an inner longitudinally extending hollow element encased within the outer longitudinally extending load bearing structural member. A plurality of reinforcement rods extend through the outer Iongjtadinally extending concrete lpad bearing structural member and a plurality of stirrups are spaced longitudinally along the inner longitudinally extending hollow element and around we element The plurality of stirrups ate in contact with the teinfoicmg rods and ettøased% flue cement or concrete in the outer longitudinally extending load bearing structural meϊhpey.

In aprefeπed embodiment of the invention a reinforced load bearing stractuxe includes steel reinforcing rods and steel stirraps that are welded together at their points of contact to form a cage like structure that is spaced from the hollow element

The invention will now be described in connection ¹ WiIh the following figures wherein like reference numerals have been used to designate like parts,

DESCRIPTION OF THE DRAWINGS

Figure 1 is a cross-sectional view of a concrete beam in accordance with a first embodiment of the invention;

Figure 2 is a perspective view of a reinforcement including steel reinforcing rods and steel stirraps as used in the first embodiment of the invention;

Figure 3 is a cross-sectional view of a concrete beam in accordance with a second embodiment of the invention;

Figure 4 is a cross-sectional view of a concrete beam in accordance with a third embodiment of the invention;

Figure 5 is a cross-sectional view of a concrete beam in accordance with a fowifc embodiment of the invention; and

Figure 6 is a cross-sectional view of a concrete slab or floor structure in accordance with a fifth embodiment of the invention. ftEscwriON ov rm. Ψmjmxsm* mmommm* OF THE myam ^Q H

A fiist embodiment of the invention will now be described in connection wha %αes 1 and 2. As shown, a longitudinally extending concrete beam 20jncludes a longitudinally extending passageway 22 defined by a pipe or tube 23 extending tfαough the beam 20 along its length. The beam 20 also includes a mass of concrete 24 surrøundiag the wbe 23 and in contact therewith, As shown, the beam 20 lias a generally rectangular cross-section, however, other shapes may be used for specific applications.

In a preferred embodiment of the invention, a plurality of steel reioforcing rods 26 extend along the length of the beam 20. For example, three longitudinally extending reinforcing rods 26 are provided on a lower side of the beam 20 and two reinforcing rods 26 are provided on an upper side thereof As shown m(n» clearly in figure 2, a plurality of steel stirrups 28 or rings are spaced apart along the length of the beam 20 and separated from the . pipe or tube 23 by a portion of the concrete 24. As shown in figure 2, the steel reinforcing rods and steel stirπφs are welded together at their points of contact 1» form a cage or skeleton,

A second embodiment of the invention is illustrated in figure 3 and is similar to the first embodiment of the invention. For example, the concrete beam 20 has a generally rectangular cross-section and a hollow passageway such as a polyvinyl chloride (PVC) pipe 23 eaftmding through the lengrø of the beam 20. However, in this embodiment of the invention we steel stirrups 38 have a rectangular shape as opposed to the circular stirrups 2$ in the first embodiment of the inventiotL The second embodiment of the invention also includes five iongtodinally extending steel remforcmg rods 26 with two of the reinforcing rods disposed hi an upper portion of the beam 20 and three reinjforcingrøds ma lower portion thereof. As illustrated me reinforcing rods 26 are disposed with one reinforcing rod ra each comer of the rectangular ring or stirrup 38 and an additional rod 26 is disposed in the bottom portion between the other two steel rods 26 on the lower portion. Figure 4 shows a tbM embodiment of the invention Wherein the beam 20 has a generally rectangular shape, a rectangular shaped ring or stkrup 38 and a plurality of loBgftT ^j dinalϊy

manner and positioning as in fee third embodiment of the invention. The difference betweeft the second and the third embodiment of the invention resides in the longifcLUΪinaHy extending hollow passageway 32. The hollowpassageway 32 fa defined by a steeltube 38 with a

embodiments of the invention.

A fourth embodiment of ihe invention is illustrated m figure 5 wherein ihe beam 20 is basically similar to the third embodiment of the invention. However, in the fourth embodiment of the invention, the hollow passageway is defined by the plastic pipe 22 Qt steel tube 33 and is replaced by a longitudinally extending light weight solid structure 42 such m a rectangular or round Styrofoam, pøly styrene foam element

A reinforced concrete slab according to a fifth embodiment of the invention is shown in figure 6. The concrete slab 50 defines a concrete base 52 or floor having a first thickness. As shown, the floor or base 52 may include a number of steel reioforckg rods 54 dispersedin a conventional manner as will be well understood by a person of ordinary skill in the art, The slab 50 also includes a plurality of parallel integral support members 60, As shown the support member 60 extend downwardly below the concrete base or floor 52 and have a thickness of about twice the thickness of the floor.

Each of the inner support members 60 includes a longitudinally extending hollow passage 22 as defined by a hollow PVC pipe. As illustrated tfre support member 60 includes the stractαre of the second embodiment of the invention. To be more specific, each of the support members 60 include a plurality of longitudinally extending reinforcing rods 26 _» a rectangular shaped ring or stirrup 38 and a hollow passageway 22 defined by a plastic pipe 23. The concrete slab 50 including the floor 52 and support member 60 are fomed ina plastic or wooden mold 65 and rests on a foundation 66 such as a steel girder.

While the invention has been described in connection with Hs preferred embodiments, it should be recognized that changes and modifications may be made therein without departing from the scope of the appended claims.