The Pensacola journal. (Pensacola, Fla.) 1898-1985, 1922-05-14
ROAD CONSTRUCTION
KEEPING PACE WITH
COUNTY'S PROGRAM
Provision Has Been Made For Con-
siderable Work During the
Coming Season
especial to The Journal.)

the stringency of the bond market dur
ing the past six months American road
and street construction is keeping pace
with the country's billion dollar pro-
gram is shown by statistics just COM
piled from official reports to the as
phalt association, this city. as to bond
issues contemplated. voted and sold
during the first TIRES months of 1922,
| compared to the last quarter Of 1921.
These reports are from states. coun-
ties, parishes townships. road districts
and municipalities, among which Es-
Gambia county, with a bond issue of
100000 for county road paving re-
ported as sold, IS one.
While the figures show the usual
winter slackening IN road building
they also indicate that provision for
street construction in the cities has
gone forward. Contemplated bond is
sues for country highways increased
from 1926. 935 900 to 1907, o0s, 200. or
SIC, 074 200. Bonds voted by the public
amounted to $90,414,T72 The bonds
amounted to SS3,154,25o. Contemplated
bond issues for streets increased from
ss.981, 945 to $26,164. 49s. a jump of $16,-
1883. Bond issues voted for streets
Increased from S2S,717, 1865 to $23,137,-
IFS, or S419,7l0, and the bonds sold
amounted to SIS. 262.972.
The rapid strides made by the cities
Of the country in street paving during
1921, as compared to 1920, Is indicated
by additional reports to the Asphalt
association from city engineers, which
say that 10000, 900 square yards
equivalent to 1850 miles Of asphaitic
pavement, 80 feet wide, were laid on
American city streets last year. Re
ports from state highway departments
indicate that 23,000,000 square yards
of asphalt We're laid on the state high
ways, while the area laid in counties
and other districts brought the total
to $4,000 600 square yards, equivalent
to 5000 miles OF asphalt pavement IS
feet wide. This is more than sufficient
to build one asphalt road Is feet wide
from Augusta, Me, to San Francisco,
Cal. and another from Augusta, Me,
to New Orleans.
According to engineers, a great
change has come over road and street
building with the realization that the
material in a road should not absorb
water, but should be water proffed.
Not only does rain sometimes destroy
a road but when frost comes, 1t will
often heave the pavement and founda-
ton On the other hand, a prolonged
drought may be very harmful to plain
macadam surfaces, which become
dusty and raveL
Impact is the new and destructive
enemy OF pavements, according to en-
gineers.. When a loaded motor truck, !
weighing, with its load, 22.500 pounds, |
and moving at a rate of 10 miles an |
hour. encounters an obstacle on the |
highway sufficient to give the wheels |
a drop Of one inch the effect upon the |
road is practically the same as though |
the total weight were multiplied by |
six In a sense the truck becomes a |
projectile and batters the payment by |
mighty impacts. Two methods of re- |
sisting impact have been developed |
among highway engineers, one being !
TO design a rigid structure which will /
withstand the impact as arTnor plate Is |
expected to Withstand the projectile. /
This method is an effort to match the |
strength of the destructive agent with |
an equal or superior strength on the /
part Of the defensive agent. 1t calls for /
constantly increasing thickness Of |
slab and more reinforcement. just as |
more powerful guns and increasingly !
effective armor- piercing projectiles !
call for thicker armor. This method |
has found considerable favor in the |
eastern states, but on the Pacific
coast engineers have for the past quar-
ter of a century been practtcing an
other method of construction, to which
they point as the infallible solutionso of
the impact problem.
In California and Oregon expert
enced highway engineers. for instance.
do not attempt to stop the mighty i'm
so to speak, but they cushion the
shock. They construct an elastic slab
which clings close to the earth be-
meath and absorbs the shock. The
western engineers argue that If you
put shock absorbers in the vehicle,
why not put them in the road? They
point to repeated tests, which have
shown that an elastic or resilient slab
shows more than double the resistance
to SCATTERING than has been shown by
a rigid slab of similar thickness and
design. At Visaiia, Calf, there is such
a pavement, composed Of seven inches
Of stone and asphalt, laid in 1894, and
in good condition today. with no outlay
for maintenance during q years. More
than 1900 yards Of this so-called
''black base type Of pavement have
been laid on the Pacific coast and over
four -ftfths of this large yardage is not II
over- five inches in total thickness. Il