US111151A - Improvement in asphaltic pavements - Google Patents

Description

UNITED Snares or both; also some ATENT FFIOE.

SAMUEL R. SGHARF, OF BALTIMORE, MARYLAND, ASSIGNOR TO HIMSELF AND HUGH M. FUNSTON, OF NEW YORK.

* meaovswisar IN ASPHALTlC PAVEMENTS.

Specification forming part of Let ers Patent No. l I 1,151. dated January 24, le'il.

- To all whom; it may concern:

Be it known that I, SAMUEL R. Sonnan, of Baltimore, in the State of Maryland,have invented a new and useful Improvement in Asphaltic Pavement for Streets and Carriageways; and I hereby declare that the following is a full description thereof: v

My invention consists of an improved asphaltic pavement and of a new and peculiar materials and method of arrangement of the making the same as a whole; and, secondly,

I in the use of a stifi bitumen, without coal-tar,

in the base or bottom layer ofa stone and asphalt pavement.

indestructible materials are wet with this inixture while hot, and then a layer of from four to seven inches put down and rolled with a roller weighing about one ton. Next Lput down a layer, say from one to two inches, of'

broken stone, which is heated and then mixed with a hot mixture of bitumen and asphalt, in.

'- the proportion of one gallon of bitumen to one-half, pound of asphalt. This layer is first rolled with a light roller, and then with a roller weighing about four tons. After this Iput on a layer, say one or twoinches thick, of a stone or fine gravel, carbonate of linie or by. draulic cement, all thoroughly mixed and wet mixture of finely-broken with the above-described, mixture of bitumen and asphalt. The mixture. o flpitumen and asphalt and also the other materials are first heated before mixing and laid down hot. This layer is course or layer. As a finishing course I spread ":2'. The use of tar, in the base of an asphalt and stone pave.

thoroughlyirolled' like the second on some dust or carbonate of lime, and again roll thoroughly.

In some cases or climates the asphalt, carbonate of lime, and cement may in whole or in' part be omitted. By using coal-tar bitumen in the base, the stones are held firmly in p place used. Thus I make a solid foundation. The

and will not work as when coal-tar is heavy oil which is added to the base serves as a reservoir to replace'slight evaporation from the surface, and thus prese'rves the life of the pavement, or prevents it from becoming brittle. The asphalt in the second and higher coats obviates thesoftening effects of the sun in summer. The carbonate of lime 'orhydraulic cement will retard or almost entirely prevent the evaporation of the heavy oil yet remaining in the bitumen; and, consequently,-preserves the life of the material, as alreadymentioned. The bitumen which I use'is made by distilling coal-tar over a slow fire, the distillation being continued as long as possiblewith out burning. or rendering'the bitumen brittle when cold. I Having thus described my invention, I

claimwhole, the same having first a base of stones. mixed with and laid in stifl'bitumen, (obtained from long-distillation of coal-tam) and then well rolled; second, a layer of smaller stones coated witha mixture of bitumen and asphalt, also rolled; third, a

layer of-- fine gravel or broken stone wet with said m1xture,likewise rolled and finally,covered*with, carbonate of a lime orwater cement, and finished 'by rolling, substantially as set forth.

stifl. bitumen, without coalment,.substantially as described;

Witnesses: SAML.'R.-SCHARF.

DANIEL BREED, 7

EDM. F. BROWN;

1. The" above described pavement as a V