US1770358A - Paving joint - Google Patents

Description

wimss A. C. F'SGHER Juy 8, 193@ PAVING JOINT Original Filso' Nov. 29

Patented July 8, 1930 4UNITED STATES PATENT OFFICE'.

ALBERT C. FISCHER, 0F CHICAGO, ILLINOIS, ASSIGNOR TO THE PHILIP CAREY MANU- FACTURING COMPANY, A CORPORATION OF OHIO y PAVING JOINT Application led November 29,1926, Serial No. 151,417. Renewed January 11, 1930.

subdivided fibrous material incorporated therein, making up a conglomerated mass which Was molded into strips of the desired dimension.

The fibrous material used for this purpose was selected primarily as a filling medium, and usually consisted of sawdust or other like ground Wood shavings, shoddy dust, sand, spent tan bark, and perhaps various other finely divided fibrous material, or a mixture of any two or more of such materials, the idea being, for the most part, to cheapen the product by the use of filling material, which is less expensive than using an all bituminous material.

Realizing the fact that a strip of paving joint made of such a conglomerated mass would be impractical to handle, due to lack of reinforcement, various means were also devised to reinforce the strip by the application of reinforcing materials to the sides of the strip. In later years I discovered that by selecting certain kinds of fibrous material and by carrying out the processes devised especially for the purposethe reinforcement on the sides of the joint could be dispensed with by internally reinforcing the strip, by utilizing certain kinds of lillinglmaterial, either especially prepared or naturally adaptable in realizing this reinforcing effect.

4The filling material which I selected forl this purpose, generally speaking Was a more or less coarse long fibre as compared to finely subdivided fibrous material, and in some instances the filler took the form of separately acting Web-like pieces, or a combination of relatively long coarse fibrous material and separately actingk web-like pieces. In any event, the idea was to develop a reinforcing structure throughout the bituminous strip, and without sacrificing,"compressibility and re-expansibility. As a matter of fact I found that I could not only develop this desirable reinforcing structure but also increase the compressibility and re-expa'nsibility of the strip by the use of such a filler, providing, of course, that it was properly incorporated in the bituminous material.

As an illustration of the results accomplislied by my previous inventions I will refer to the use of excelsior as the relatively long coarse fibrous material, the use of the same being described in my Patent No. 1,582,880, issued April 27, 1926, and as an example of the separately acting Web-like pieces I will refer to my Patent No. 1,572,474, issued February 9, 1926, which describes the use of roofing scrap as separately acting re1nforcing pieces. As still another illustratlon of materials suitable for developing these separately acting web-like reinforcing pieces I will also refer to my Patent No. 1,591,968, issued July 13, 1926, which describes the use of flake material.

Inall these previous developments in the art I have manufactured the material by utilizing practically the same process,.that is to say, which briefly consists in utilizing a meclianicalsteam-jacketed mixer, into which is introduced melted bituminous material and to which is added fibrous filling materials, mixing the materials thus introduced into the mixer into a homogeneous conglomerated mastic mass, then removing the mass from the mixer and while the same is in a Warm plastic flowable condition introducing the mass to a sheet forming apparatus, setting up a flow in the mass as it lays against the receiving end of the sheet forming apparatus, and straightening out the fibres in the direction ofthe fiow of the material thru the apparatus, to thus convert the material into sheet form, with the filler distributed in substantial parallel strata, many of the pieces separated one from another by a substantial thickness of the bituminous material. As a result of this process the tensile strength of the strips ultimately cut from the sheets thus formed would be greatly increased, and resistance to cracking, breaking and even bending would be increased to an effective degree.

To better explain the reinforcing structure as a result of selecting certain fibrous material and resorting Y to the process here explained, I have referred to the same as a felted matted mass of fibrous material, compressed in substantially parallel strata. The resulant product would be a strip comprising a single layer of felted fibrous material of sufficient thickness to form a complete paving joint permeated with bituminous material. Such a structure is distinctively different from a conglomerated mixture of bituminous and finely subdivided fibrous material in that the bres of the matted structure would cling together even after the asphalt was extracted, whereas a conglomerated mass of finely subdivided fibous material and bituminous material subjected to an extracting process would leave the finely subdivided fibrous material free to fall apart, with no semblance of a matted structure. When combining separately acting web-like reinforcing l pieces in such a matted structure the pieces would be distributed thru the matted mass in parallel strata, and separated one from another by. thicknesses of the fibrous matted structure and the permeated bituminous material.

My present invention relates to the same subject matter of invention as explained with reference to my earlier developments, and distinguishes from a conglomerated mass of finely subdividedwfibrous material and bituminous material in the same way and for the same reasons as explained with reference to my earlier developments. Furthermore, the present invention distinguishes from my earlier developments in the selection of the fibrous material used.

Ordinarily the selection' of one kind of librous material for that of another would not amount to patentable invention, but in this particular instance it is not so much a matter of substituting or selecting one fibrous material for another simply for the sake of economy, or other unsupported practical rea# sons as it is the selection of certain kinds of fibrous material which will accomplish certain results that previously known materials are not qualified to produce. In other words, the use of excelsior is known to me to develop certain inherent qualities in the resultant product, the use of separately acting web-like pieces of reinforcing material is also known to me to develop certain inherent qualities in the resultant product, likewise a mixture of these two fibrous materials will develop other qualities.

The materials selected for the present invention are known to me to have certain inherent qualities which will accomplish results that are totally lackin in other known materials. The detail o? these distinguishing features will be fully described as the description now proceeds with reference to the accompanying drawing.

`The salient feature of the present invention resides in the selection of cotton-seed hulls, either alone or in combination with other filling material as a reinforcing filling medium for preformed bituminous paving joints.

In the drawing Figure l is a detailed perspective view of a fragment of a cotton-seed hull exaggerated for the purpose of showing as much as possible its characteristic structure which makes it especially adaptable as a reinforcing filling material.

Figure 2 is a view in perspective of a matted mass of these fragments shown in F igr ure 1.

Figure 3 is a perspective view of a portion of a preformed strip of paving joint showing the fragments of cotton-seed hulls felted into a mat and permeated with bituminous material; and

Figure 4 is a view similar to Figure 3, but showing the addition of separately acting web-likev reinforcing pieces and long fibres incorporated in combination with the felted fragments of cotton-seed hulls.

These fragments of cotton-seed hulls'are obtainable on the market as a more or less waste product, and, as clearly shown in Figure 1 the fragment of the shell l is covered with more or less thickly clustered cotton linters 2, which are the unsalvaged fibres of the cotton. The shell fragments for the most part are concave and will be found in irregular shapes, some of which having jagged edges and points, which develops aroughened uneven margin, and the inside surface of the fragments shown as at 8 are pitted and roughene The nap-like clustered linters covering the convex outer surface of these fragments give to the fragment the quality of adhering to another fragment, so that by bringing a quantity of these fragments together the nap-like covering of linters will intertwine or interlock so that the fragments cling together and yet are separated for the most part by a loosely matted nap of linters. This is clearly shown in Figure 2.

A quantity of these fragments matted together in this way leave an unusually compressible matted mass. Consequently by mixing a quantity of these fragments of bituminous material so as to develop a felted matlike strip permeated with bituminous material, by resorting to the process heretofore described I am able to develop a highly compressible paving joint which has unusual reexpanding qualities, and a strip thus formed will compensate for expansion of the concrete sections between which it is installed with the greatest efficiency. As an example, upon expansion of the concrete sections, which will impart pressure to the sides of the strip, the joint will readilyl respond to such pressure,

and thus yielding compressibility will permit the sections of the concrete to expand.`

A' practical paving joint is not only expected to compensate"for expansion of the concrete, but it must also be so constructed that it Will compensate-for contraction. For instance, Whenthe sections contract the concrete theoretically moves away from the oint, thus enlarging the space occupied by the joint. Now, unless the material of the joint is capable of expanding and completely filling this enlarged space a crevice will be left between the sides Aof the jtint and the concrete sections which will eventually be filled up with dbris, Water, street acids and other deteriorating matter which would destroy the functioning of the joint. A joint constructed in accordance with the presentin-v vention, will, owing to the highly compressible and re-cxpanding qualities of the matel rial's used, keep this space completely filled 1 upon contraction of the sections.

Aside from the advantages above explained these fragments of cotton-seed hulls have other ingredients which improve the qualities of the paving joint, and these advantages are best brought out by a comparative explanation.

Comparing these fragments to other hulllike materials, viz., rice hullsv or the equivalent, it is a fact that the smooth, shiny surface of rice hulls, or any other grain hulls, offer little if any resistance to slipping in the bituminous material, especially at temperatures which are apt to soften the bituminous material, whereas the jagged edges of the cotton hull fragments,' the inside pitted' roughened surface as at 3, Figure l, and the concave continuity of the fragments. offer jagged and roughened projections to which vthe asphalt will adhere and cling much better than the smooth' and comparatively glossy surface of other hull-like materials.

This vresult is also emphasized by the ini terlocking of the nap-like linters covering the vouter surface of the fragments, part1cularly when it is considered that a part of these fragments are embodied in the strip as a felted mat with the bituminous material permeating the same.

The parallel stratification of these cottonseed hulls is notas pronounced as in the case of the use of pieces of filling material that are longer than their width or thickness, but the same principle is involved, particularly with respect to those fragments of cotton-seed hulls which happen to be crushed in pieces large enough to respond to the flow set up in the Warm, Howable mass bythe sheet forming apparatus, and vin a quantity ofA these fragments of cotton-seed hulls there willbe many fragments large enough to respond to this result.

In Figure 3, 4 represents the paving joint, 5 the hull fragments and 6 the interlocked or intertwined nap of cottom fibres, the latter developing the ,matted felt-like massv of However, to increase the content of this par-V ticular kind of a filler I may use roofing scrap of the same kind as explained in my Patent No. 1,572,474, issued February 9, 1926, and hereinabovereferred to. Figure 4 shows the same type of joint illustrated in Figure 3, i

but With the addition of the pieces of roofing scrap as at 7, and long fibres 8.

In addition to these fragments of cottonst j seed hulls I may also desire to use long fibrous material, such as, cocoanut fibre, sisal,

,'hemp, jute, or any other suitable equivalent long fibre, and I might use such long fibres not only in combination with the fragments of. cotton-seed hulls but also in a mixture in which the roofing scrap or other separately acting Web-like reinforcing pieces are used.

yIn any of the mixtures that I would develop from the materials referred to I would preferably use a preponderance of bituminous material, .and I Wish to emphasize this point, as it is invaluable in producing a practical type of joint.

In some rare instances there is a possibility that per cent bituminous material and 50 per cent by Weight of these fragments of cotton-seed hulls will be. acceptable, but never would I use less than a 50-50 mixture, and more frequently, in order to meet the specifications -for the standard preformed paving joint material, I would recommend approximately per cent bituminous material and 25 per cent by weight of fragments of cottonseed hulls. It will not be necessary for me to go into detail as to Why a preponderance of bituminous material is used, since those skilled in the art recognize this requirement `as an unfailing necessity, and-to the best of my knowledge there has never. been an acceptable paving joint which has not contained a preponderance of bituminous material.

It is, of course, understood that when I say 7 5- per cent bituminous material and 25 per cent fragments of cotton-seed hulls I use they term approximate to leave me a reasonable leeway one way or the other, for it may well be that I could cut the bituminous material percentage to as low as 60 per cent,

and may even find some instances Where bituminous material, and an acceptable combination of such a mixture would be 75 per cent bituminous material and 25 per cent filling material. As a more detailed explanation I may recommend 75 .per cent bituminous material 2O per cent fragments of cottonseed hulls and 5 per cent long libre, such as, cocoanut fibre, sisal etc., or 75 per cent bituminous material, 15 per cent fragments of cotton-seed hulls and l0 per cent roofing scrap. These proportions are all measured by weight and not by bulk.

I have heretofore discovered that a rubber content in proportion sufficient to add elas- .ticity to the preformed strip is an acceptable addition to any expansion joint material, and the same would apply equally well to the combination explained in the present application. In theevent that the rubber content was added it would be in the form of either uncoagulated latex, reclaimed rubber, rubber latex, or any form of liquid rubber, and it would be added preferably during the mixing process. There is one consideration in the addition of a rubber content, I would not have to use, in this event, a preponderance of bituminous material as the rubber content would supply the difference in a lower ratio of bituminous material, say for instance 50 per cent bituminous material, 20 per cent fragments of cotton-seed hulls by Weight, 10 per cent roofing scrap by weight and a 20 per cent rubber content There is another qualifying statement that should be explained to interpret the scope of the present invention as recited in the subjoined claims. I have been referring to bituminous material. The bituminous material is in reality a binder, and for the most part Iwould prefer to use blown asphalt or oxidized asphalt as a binder. However, due

i to the fact that a rubber content, such as above explained, used in combination with road oil or a macadam binder will take the place of blown asphalt and `oxidized asphalt I will use the term waterproofing binder as embracing bituminous material or its equivalent.

In reciting the invention in the accompanying claims the terms road oil and macadam binder are intended to embrace those materials, or the equivalent to the same as identified by Herbert Abrams in the book entitled Asphalte and Allied Substances the 1918 edition.

While the relatively long fibres, such as cocoanut fibre, hemp, sisal, and the like, are used for the reinforcing properties that they will lend to the strip, they also lace the disintegrated cotton-seed hulls together by inter-` twining with the nap-like cotton fibres on the outside of the hull fragments, so that the felted mat thus formed is practically sewed together so to speak. This interlacing or interlocking of the fibres in the mat structure is performed during the mixing operation.

I claim:

1. An expansion joint comprising a preformed strip embodying 'in its structure a felted mat of disintegrated cotton seed hulls, the outer surface of the disintegrated hulls containing a nap-like covering of unsalvaged cotton fibres, and said mat being permeated with a wateproof binder.

2. An expansion joint comprising a preformed strip embodying in its structure a felted mat of disintegrated cotton seed hulls, the outer surface of the disintegrated hulls containing a nap-like covering of unsalvaged .cotton fibres, said mat being reinforced by a lacing of relatively long bres and permeated with a waterproof binder.

3. Constructional material comprising a preformed body consisting of a homogeneous mixture of a waterproofed binder and cotton-seed hulls.

4. Preformed constructional material comprising a homogeneous mixture of a waterproofed binder and hulls having cotton fiber emanating therefrom, forming a mat-like structure in the homogeneous mass and the fiber surrounding the hull sections.

5. Preformed constructional material comprising a bituminous structure having cotton linters distributed therethru, and cottonseed hulls interspersed within the linters.

6. The method of preparing a preformed contructional material comprising the mixing of cotton-seed hulls having cotton fiber emanating therefrom, in a waterproof binder and reducing same to sheet form.

7. The method of preparing a constructional material which comprises the steps of preparing a. liquid, heated, waterproof binder, mixing therein cotton-seed hulls having cotton fibers emanating from the hulls, and pressing same to the desired form.

8. The method of forming a brous, matlike structure in a preformed, bituminous constructional material, which consists in incorporating cotton-seed hulls and cotton fibers in a liquid, waterproof binder thru a mixing operation, cooling same and reducing same to proper form.

9. The process of preparing a preformed. constructional material which consists in treatin cotton-seed hulls, having cotton ber emanatmg therefrom, with hot water, subsequently drying said fibrous material and in, corporating same into a liquid Waterproofed binder, suitably mixing the same and subsequently cooling and reducing to proper form.

10. The process which consists in treating cotton-seed hulls, having cotton bers emanating therefrom, with asolution of heated water and two er cent caustic soda, suitably cleansing the ber so treated, drying same, mixing with a waterproofed, liquid binder by a suitablemixing device, cooling same after being mixed, and reducing same to proper form.

11. The method of preparing e preformed constructiona meteriei comprising the mixing of seed huiis, having iinters emanating therefrom, in a, Water? ooang binder, ineor pointing linear ber@ in the mixture, and reducing the in eieet Iform.

12. Preformed oonetructionai materia comprising a bituminous mass having distributed therethru cotton fiber and granular fibrous materiein 13. Constructionel :materiel comprising a preformed body @ons i A. ng of a homogeneous mixture of a wete 'eing binder and seeds, said seeds having siieii covered with emenating linteie0 14. Construotionei materiel comprising a preformed body consisting of a homogeneous mixture of e ifeterpiooiled binder,- seeds having a. shell covered with emanating linters and fibers intermingied with the seeds.

Signed at Chicago9 illinois, this 24 day of November, 1926.

ALBERT C. FSCHER.

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