The Abbeville press and banner. [volume] (Abbeville, S.C.) 1869-1924, 1902-09-03
GOVERNMENT ROADMAKlNG.
Work a Construction Supplemented
Iectpres by an Expert.

Work a Construction Supplemented BY
Lectures by an Expert.
Several weeks ago the department Of
agriculture began its first experiment
in roadbuilding at New Brunswick,
N. j., under the direction Of e. b.
Harrison, special agent Of the Office Of
soad inquiry.
The model road being considered is
the first of several which the govern.
ment is to build at the various expert
ment stations throughout the country.
The government furnishes rock crush
er, screen, engine to drive steam roller,
spreading wagon and road grading ma
chine and two skilled operators. The
city furnishes the material, carts and
laborers.
The road will be Of macadam pattern.
An inferior grade Of traprock is found
in abundance near New Brunswick and
this 10 being used in the substructure
of the road. The superstructure is OBJ.
tanned from the traprock deposits in
the neighborhood Of Plainfeld and the
Oranges.
The model pavement will have .
depth Of about nine inches and the foun-
dstion be mado of small, wedge shaped,
broken stones Of as nearly the same di-
mensions a. possible. The roadbed will
be prepared by thoroughly rolling with
Q steam roller weighing about ten tons.
Every hole will be carefully filed with
the same material that composes the
rest of the roadbed, and the finished
cross section will be formed by two
grades of one foot in 80 feet from the
sides, uniting at tho center, with the
apex slightly rounded. Four inches OF
crushed stone will be spread on the
carefully prepared roadbed to form the
foundation Of the substructure. The
largest Of these stones will be crushed
% fne as to be able to easily pass
through two inch ring, and the small
est will be about half IN inch In diam
eter.
This foundation will then be sprin-
kled, making he stone as wet as posi-
bic without softeniug the roadbed, and
the roller passed over 1t few times
until the stone is only slightly disturbed
by the teams returning with the empty
carts. The first foundation is not made
deeper than four inches, because 1t has
been found that greater thickness
causes the stones to "elbow" together,
wearing of their sharp corners, making
the bonding " which is the great de-
sideratum, very slow process, II not
an impossibility:
When the first Foundation has been
thoroughly sprinkled, second coat OF
similar stone three inches in thickness
will be applied. After the stone has
been well bonded" to this extent 1t will
again be sprinkled. and while very wet
Q thin coating f traprock screenings
will be most carefully spread over tho
surface, Just thick enough to fill the
small spaces between the stonea The
size Of the stones of this last applica-
ton, which is called in the parlance Of
roadbuilding the. "binder," will be
from half an inch in diameter to the
finest dust. When the work has reached
this stage, it will be left untouched in
the dry state as long as practicable to
harden and bind. The application OF
water and the passage Of vehicles will
be prevented as long as practicable.
As the work progresses Mr.. e. B.
Harrison, who is directing the work for
the department Of agriculture, will de-
liver lectures explaining the. process Of
laying the road. Rutgers college stu.
dents in the agricultural department
and farmers will be, invited to attend
the lectures and witness the work.