US1519560A - Paving composition - Google Patents

Description

Patented Dec. 16, 1924.

PATENT OFFICE.

CHARLES SWAN, OF SAN FRANCISCQ-CALIFORNIA.

PAVING- COMPOSITION.

No Drawingl To all whom it may concern:

Be it known that I, CHARLES SWAN, a citizen of. the United States, residing at San Francisco, in the county of San Francisco and State of California, have invented certain new and useful Improvement in Paving Compositions, of Which the following is a full, clear, and exact description.

My invention relates to concrete compositions for pavements and sidewalks which contain as a binder solid bituminous products, such as asphalt and mineral pitch, and an object of my invention is to increase the toughness, elasticity and durability of such compositions.

The subject matter ofthisapplication is the same as that of my former, abandoned application, Serial #247A7 9, filed July 31, 1918. I

The improved qualities of my pavement are due essentially to the use of diatomaceous earth in the composition. 1 have discovered that diatomaceous earth, when added in a proper proportion to the composition, not only causes the pavement'to be unafiected by temperature changes, but also is cementitious in its effect and amalgamates the concrete, and toughens the avement and renders it more elastic an durable. The diatomaceous earth may be mixed into the asphalt or bitumen mixture while the latter is hot, or it may be mixed into the mineral filler, or it may be divided between the binder and filler before the two are mixed.

According to conditions, I have found that. when mixed into the binder,-the pro portion of diatomaceous earth can vary from approximately 10% to approximately 35%. For most uses in paving materials, the binder or bitumen mixture may contain approximately from 55% to 85% of asphalt, from 5% to 10% of crude petroleum oil and from 10%-to 35% of diatomaceous earth. Usually about of diato: maceous earth is sufiicient. The filler or base of the paving composition may consist,.as is usual, of crushed stone and sand. A suitable avement may be made of a filler consisting of crushed stone of a size the pavement is laid ping is formed of Application filed August 8, 1924. Serial No. 730,907.

from approximately three inches square and all the smaller stone down to the dust of the stone which results from the crushing and which is mixed in the concrete.

As an example of a durable pavement, 5 fine sand up to meshes to the square inch and coarse sand to one-quarter of an inch square is mixed in with the crushedrock, and this mixture is put in a vessel where it is agitated and subjected to heat. When 60 this base material or filler is dried and heated so that all the moisture has escaped, the binder or bitumen mixture, composed of asphalt, crude petroleum oil, anddiatomaceous earth in proper proportions is passed into the vessel With the base material. This mixture is agitated sufiiciently to thoroughly mix into a bituminous concrete, after which it is transported to the place where and uniformly raked-7 out and then rolled and stamped sufficiently to make the pavement compact.

The concrete pavement is laid on a dry, solid base to any desired thickness. When a pavement of less than three inches is laid,

the size of the crushed stone will be regulated accordingly. The top or surface capa sprinkling of the bitumen mixture of asphalt, crude petroleum oil and diatomaceous earth, which may be 'mixed in the usual way with sand, to make the pavement water-proof and prevent slipperiness. I have also found that coarse horse hair or other kind of hair is an excellent substitute for or addition to the sand for this purpose. In case of a sidewalk, fine and coarse sand is mixed with the bitumen binder composed of asphalt or any bituminous material, crude petroleum oil and diatomaceous earth, and the mixture is rolled or otherwise properly compacted.

I claim:

1. A binder mixture for pavements and the like consisting of a solid bituminous product, diatomaceous earth and petroleum oil.

2. A paving composition consisting ofa solid bituminous product, crude petroleum, diatomaceous earth, sand and crushed stone.

3. As a'paving composition, the combination of a binder of solid bitumen, diatomaceous earth and crude petroleum, and a filler of pulverized rook, I

4. Aswe, paving composition the combination maceous earth and ci'ude petroleum, and a filler of crushed rock ands'and.

5. As a paving composition the combinaof a binder of solid bitumen, diato tion of a binder of solid bitumen, diatomaceous earthv and crude petroleum, and a In Witness whereof, I hereunto subscribe my signature.

CHARLES SWAN.

varying size including the stone 1