The Abbeville press and banner. [volume] (Abbeville, S.C.) 1869-1924, 1902-10-29
GOVERNMENT RoADMAKiNG.


Wsrk q Construction Supplemented ~
Lectures By IN Expert
Several weeks ago the department Of
agriculture began its first experiment
in roadbuilding at New Brunswick,
MI, under the direction Of e. b.
Harrison, special agent Of the ofsioe Of
soad inquiry.
The model road being considered II
the first of several which the govern
ment 10 to build ut the various expert
ment stations throughout the country.
The government furnishes rock crush
o., screen, engine to drive steam roller,
spreading wagon and road grading ma
chine and two skilled operators The
city furnishes the material, carts and
labofera
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 tho road. The superstrucsure is OBJ.
tanned from the traprock deposits In
the nsighborhood Of Plainfeld and tho
Oranges.
The model pavement will have .
depth Of about nine inches and the foun-
dation be made Of small, wedge shaped,
broken stones Of a. nearly the same di-
mensions as possible. The roadbed will
be prepared BY thoroughly rolling with
. steam roller weighing about tan tons.
Every hole will be carefully filed with
the same material that oomposes the
rest Of the roadbed, and the finished
crou section will be formed BY two
grades Of one foot In 30 feat from the
sides, uniting at the center. with tho
apex slightly rounded. Four inches Of
crushed stone will be spread ON the
carefully prepared roadbed to form tho
foundation Of the substructure. Tho
largest Of these stones will be crushed
% fine % to be able to easily pass
through Q two inch ring, and the small
eat will be about half an inch in diam
eter.
This foundation will then be sprin-
kled, making The stone a. wet as posi-
bic without softening the roadbed. and
the roller passed over 1t few times
until the stone 10 only slightly disturbed
By the teams returning with the empty
carts. The first foundation IL not made
deeper than four inches, because It has
been found that q greater thickness
causes the stones to "elbow" together,
wearing of their uharp corners, making
the "bondipG which 10 the great de.
sideratum, . very slow process. It nos
IN impossibility.
When the first foundation has been
thoroughly sprinkled, q second coat OF
similar stone three inches in thickness
will be applied. After the stone has
BEEN we'll "bonded" TO this extent 1t will
again be sprinkled. and while very wet
Q thin coating Of traprock screenings
will be most carefully spread over the
surface, Just thick enough to I'LL the
nuall spaces between the stones. The
size of the stones Of this last applica.
ton. which 10 called in the parlance Of
soadbuilding the binder" will be
from half an inch in diameter to the
finest dust. When tho work has reached
this stage. it win be left untouched in
the dry state as long as practicable to
harden and bind. The application Of
water and the passage Of vehicles viii
b prevented as long as practicable.
A 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.