Daily press. [volume] (Newport News, Va.) 1896-current, 1908-11-22
HAMPTON PHOEBlJS AND OLD P0lN1-Continued -
RUBBER ASPHALT ON
ROADWAYS OF FRANCE

! In answer TO an inquiry. tohsui
General Robert p. Skinner iurmsn''
1.-The following information concerning
Irubber-asphalt pavements In France
! Experiments. covering periods o
six wears, have been made with this
pavement In several cities Throughout
France, including Paris ana Lyons
and as far as can be ascertalned Ha'e
given good results.
In the city OF Marseilles a satisfac'
tory experiment was made upon the
| prado a Number of years ago. and THIS
spring three or four public places
we're similarly paved. these areas
however. Icing devoted to pedestrian
traffic exclusively. Innovation or TINS
kind make slow progress in France
but from the character Of the men III
terested in the company and the H.
creasins importance Of the work I'M
dertaken rubber asphalt paving must
be regarded very seriously as a SUP
stitute for the more usual form or
asphalt paving.
At the present time most aSphait
paving involves the use OF costly III
stallations for the heating of the pow
der a considerable amount OF mater
iai and special class of laborers. all
of which tend to increase the cost.
Under the new process 1t is posslbie
to make cold applications or asphan'
which are said to possess all the al
vantages Of hot compressed asphalt
without It's drawback.
Material Used and Its Applications.
The material under description is
product resulting from the as
sociation of asphalt and rubber.
Ashpalt is carbonate of lime i'm
ORIGINATED with bitumen, with which
rubber combines under certain con
ditions. thus effecting the cohesion OF
the calcareous molecules. This pro
duct is claimed to be more plastic ana
more adhesive than pure ashpat. ana
to resist higher temperatures. To Cd
tain the combination of htumen ana
rubber they must be theoretically mix
ed in special devices. in which the
asphalt. reduced to fine powder. Is In
the presence of rubber swelled ana
softened by a solvent. The material
thus obtained is d brown powder dark
er than the original asphalt. and II
sufices to compress it in order that
il shall set and harden rapidly.
1t is alleged that when asphalt Is
applied hot. the heat Of the appllca-
ton coming into contact with a con-
crete foundation containing more or
less humidity vaporiZes the water con-
tanned therein, and the steam. by It's
force Of expansion. escapes. thus de-
stroyinx the compactness OF the com
bination. This Inconvenience does
not present itself in the system I'M
der designation. which Dermits the ap
plication of a much thinner layer OF
asphalt and Qne which unites itself
with the concrete. constituting solid
mass. The observations Of this form
of pavement satisfy those interested
in the subject that the completed sur
face resists ordinary wear more SAT
isfactory than any ether
Rubber-Aspha,t Pavements.
Rubber-asphalt must be applied up
on a foundation of firstclass concrete.
consisting of 44O pounds OF good Porl.
land cement and l cubic meter 600
cubic feet Of pebbles and SAND. the
proportions being one-third Of sand
to two-thirds of pebbles. The thick
ness of the foundation should vary
from Is to 20 centimeters $3.50 10
'7.s7 incheS) and it should be rammeu
with the back Of shovels used in TINS
work. and given the exact form which
the roadway is intended to have. with
out the necessity of making later al
ditions Of concrete to bring the sur
face to its proper proportions. Inc
surface of the concrete should be
regular. so that the layer OF asphalt
NAV have a uniform thickness. 1nls
foundation should remain three W
five days. according 10 the season. un-
til it has acquired sumcient Halu'
ness to support the ramming OF the
layer of asphalt. The surface OF con-
crete having been well cleaned, IS
covered with a thin coating Of special
material. whichs Is laid on with a
brush upon which the rubber-asphait
powder is lightly sprinkled. Shortly
after these preliminary operations the
uniform layer Of rubber-asphalt pow
der is spread to a thickness OF SO 10
centimeters G.37 to Isl inches)'
which Is compressed progressively by
, means If a rammer. This done. the
surface may be opened Immediately
to travel. It is said that by this PRO
cess the top-dressing Of asphalt. when
laid on hot NAV be cne-half the thick
/ ness necessary when the asphalt Is
laid on cold.
As the process is covered BY pat
! ent and exploited bv a particular com
nanv. il is impossible. Of course. u
S.scr;,r tac system otherwise than II