US691708A - Roadway. - Google Patents

Description

Patented lan. 21, |902.`

F. A. MALETTE.

ROADWAY'.

(Application led Nov. 27, 19.01.)

(No Modell) TN: Ncnms PETERS co., Pnmnumm wAsuxNoroN. u. c.

UNITED STATES lPATENT OFFICE.

FREDERICK A. MALETTE, OF GENEVA, NEW` YORK, ASSIGNOR OF ONE-HALF TO EDWARD SEYBOLT, OE GENEVA, NEW YORK.

' ROADWAY.

SPEGIFICATIQN forming part of Letters Patent No. 691,708, dated January 21, 1902.

Application filed November 27, 1901. Serial No. 83,927. (No model.)

To @ZZ whom t may concern:

Be it known that I, FREDERICK A. MALETTE, a citizen of the United States, residing at Geneva, Ontario county, New York, have invented certain new and useful Improvements in Roadways, of which the following is a specification.

My invention relates to roadways, and is in the nature of an improvement upon the construction described in Letters Patent No. 683,056, granted September 24, 190i, jointly to myself and Edward Seybolt.

The chief aim of this invention is to avoid the turning or rolling of the fragments of stone when subjected to heavy pressure after theyhave been individually coated with bituminous material and placed upon the foundation or bed; also, to provide a better top-dressing, which covers the protruding tops of the stones and iills the spaces between such tops and acts as the primary, though temporary,

wearing-surface of the roadway.

In crushing stone in the large stone-crushing machines and, in fact, in any system of stone-crushing there is a percentage of small material consisting of stone-dust,stonescreen ings, or small particles of stone. test it has been ascertained that the use of a small amount of such material as it comes from the crusher when deposited in the voids will effeetually prevent the fragments of the pavement from rolling, creeping, or sliding under heavy pressure. It is not necessary to use a sufficient quantity of this material to entirely fill the voids, thus adapting the small particles of stone to act as chocks or wedges -which prevent the larger fragments from turning, shifting, and rolling out of position. Experience has also demonstrated that with respect to the surface-coat or top-dressing the best results are obtained by using tarred screenings or sand and the like placed loosely over the protruding tops of the stones and filling the spaces intervening between such protruding tops. When such dressing is quite thin, it wears away too rapidly between the stones and is productive of an irregular wearing-surface. Therefore the final coat of sand or tarred screenings, or both, is made of greater thickness, as compared with that described in the patent above referred to, with By actualV the result thatthe wear caused by the abrasion of vehicle-wheels eventually brings the stones to the surface with the spaces between the protruding tops completely filled, thus at--i taining a regular and practically continuous or unbroken wearing-surface of stone.

The accompanying drawing represents a sectional view of a roadway constructed in accordance with the present invention.

A designates the surface-coat or top-dress ing constituting the initial temporary wearing-surface'of the roadway; B, the layer composed of fragments of broken stone, the voids between which are partially filled with smallparticles of stone, screenings, or dustand indicatedv at b, and C the foundation or initial layer, which is placed directly upon the subgrade. v

The foundation C may consist of concrete" 7o or any ordinary and well-known rpavementfoundation material,or a combination of both, the composition of such foundation being immaterial to the present invention. Upon said foundation is placed the layer B of brokenf stone as it comes from the crusher, the said broken stone forming the ultimate Wearing! surface vof the roadway. The fragments of stone composing the layer B usually vary in size from one-quarter of an inch to two inches 8o in diameter, enough of such material being employed to produce a layer of approximately three inches in thickness, the thickness, however, depending to a considerable extent upon the kind of trafiic for which the roadway is designed.

The pieces or fragments of stone are primarily coated with bituminous material, such as coal-tar or other pitch, a sufficient quantity being used to merely coat the fragments onf 9o all sides without filling the voids after the fragments are laid on the foundation-layer and compressed. This coating causes the fragments to adhere firmly together and constitutes a complete and effective bond when the layerB is subjected-to the pressure of a steam or other roller. The roller should be heavy IOO pressure, resort is had to what may be termed an antislipping filler b, which is composed of the smaller particles of material coming from the crusher, and consisting of stone dust, screenings, and the like. A sufficient quantity of this is used to partially fill the voids and occupy the lower portions thereof. The filling material may be used just as it comes from the crusher, or it may be treated with bituminous material and partly or wholly coated therewith. When the filler is deposited in the voids, it works its way partly beneath the stones and acts to wedge the same firmly in position, so that the stones will not turn, shift, or roll after they have once settled firmly in place. The bitumen insures adherence of the particles of the filler to the underlying as well as the superposed fragments, resulting in a practically rigid and unyielding roadway well adapted to all kinds of traffic.

Upon the layer B is placed a surface-coat or top-dressing A of tarred stone-screenings or sand, or both, the same being laid loosely, so as to fill the spaces between the protruding tops of the stones and also cover the stones lightly. The effect of traffic is to force the surface-dressing firmly and compactly into the spaces referred to. Eventually the stones appear at the surface and in reality form the permanent wearing-surface of the roadway. Ordinarily that portion of the top-dressing which covers the stones lasts but a few weeks, or at most a few months, and thereafter the finished roadway shows a stone top surface which is perfectly rigid.

The stones when freshly coated with bitumen are oily and slippery and in many instances without the use of the filler and even when bonded together spread and shift themselves about under the pressure of a heavy roller. rThe filler serves to lock and Wedge the stones against such movement. It is also important not to completely fill the voids, as too great a quantity of filler would form a yielding,` bed upon which the stones would roll'and shift under pressure and prevent proper and effective bonding.

Having thus described my invention, what I claim, and desire to secure by Letters Pat ent, is

1. A roadway comprising a foundation, a layer of broken stone of varyingsizes thereon forming the wearing-surface of the roadway, the fragments of stone being individually coated with bituminous material, which forms a bond between the fragments when the latter are subjected to pressure, and an antislipping filler of stone-dust, stone-screenings or the like partially filling the voids between the fragment-s and forming chocks which pre vent the turning or rolling of the fragments under pressure.

2. A roadway comprising a foundation, a layer of broken stone of varying sizes thereon forming the wearing-surface of the roadway, the fragments of the stone being individually coated with bituminous material which forms a bond between the fragments when the latter are subjected to pressure, and an antislipping filler of stone-dust, stone-screenings or the like treated with bituminous material and partially filling the voids between the fragments, said filler acting as a chock topprevent the turning or rolling of the fragments under pressure.

3. A roadway comprising a foundation, a layerof broken stone of varying sizes thereon, the fragments of stone being individually coated with bituminous material which forms a bond between the fragments when the latter are subjected to pressure, a filler of stonedust, stone-screenin gs or the like partially lling the voids between the fragments and acting as a chock to prevent the turning or rolling of the fragments under pressure, and a surface-coat or topdressin g of tarred screenings or sand covering the protruding tops of the fragments and filling the spaces between such tops.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

FREDERICK A. MALETTE. Witnesses:

C. T. CHURCH, W. S. Woon.

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