The aegis & intelligencer. [volume] (Bel Air, Md.) 1864-1923, 1922-01-20

triumph.
Yours in His Service,
(SignedD, WILLIAM Nee. MILLER
ROAD BUILDING NOW REDUCED
TO A SCIENCE
state highway departments the coun-
try over are now in the midst OF u
busy season, huriying to complete
plans and specifications for new high
way construction to be started in the
spring under the added impetus of the
recently enacted $75,0O0,000 federal
aid bill. These plans are perhaps iar-
ther advanced this year than hereto
fore due to the urgent request Of See
rotary of Commerce Herbert Hoover
for the early letting of contracts Ia
one means of atfording relief from un-
employment.
Up to the present time federal fumes
to the amount of $2ll ,l35, }i6 have
be ~ allotted to the states as the Huv-
eInments share in highway construt
ton under federal aid since its insti-
tuition in 1916, according to the latest
announcement of Thomas y. MaIDon
aid Director of the U. $. Bu,pal Of
Public Roads. The total rIss of all
the projects in which the federal gov-
eminent has shared expense, including
state and local funds, has ussn $780,
Isl 1888, the bureau announces.
Practically all forms If moheln
highway types have been constructed
under the various acts appropriating
federal money, including vitriticd brick
macadam, sand clay, asphaltic and ce-
ment, concrete and gavel. Altogether
the mileage built or approved has
reached total of 28,l36,
In addition to exercising general SUI
pervisiOn over federal aid expenditures
the Bureau of Public Roads is continu-
ally making scientific studies of pave
ment construction and behavior N or
der to make available to highway en-
gineers, public officials and the public
in general reliable and official info"ma-
ton concerning modern highway en-
gineering practice.
These scientific studies are conduct
ed both at the governmental station ut
Arlington, and in the field where the
behavior Of highways in actual use
may be observed
As an example of the nature Of the
mcnt stationed can be mentioned the
recent studies of sub-soil conditions
and the pavement over the sub-soil,
which studies revealed the fact that
concrete pavements, for instance, curl
up and down at the edge under the
heat of the sun. Another instance of
the bureaus activities are the tests of
brick and concrete pavement specimens
determine their ability to withstand
impact or shock as IL might be impart-
ed to them by the wheels of heavily
oadcd motor trucks.
A typical illustration Of the work
done in the field by the bureau IL the
recent report of survey of brick
pavements on rolled gravel, crushed
stone, Or Stag bases. This report,
pointing out the adaptibility of local
materials, easily available and at
minimum cost, is made public in the
current issue of the bureaus official
publication Public Roads"
In 1920 the bureau tentatively list
ed the various types Of pavements ac-
cording to their service value, based
on experience up to that time, in the
following order:
!. Brick on concrete Dase; Shcet
'sphalt on concrete base; 3 cement
concrete; q Bituminous concrete; b hi
luminous macadam; Surface treated
maeadam; waterbound macadam;
gravel macadam, gravel, 10 sand
clay.
In view OF the fact That concrete bus.
cs were the only type specifically listed
ut that time the recent official report
ON an investigation OF rolled gravel,
crushed stone and Stag bases, pointing
out their service records and length
OF IRE, and at The same timc cmphasz-
ing the availability OF the material in
territory where gravel banks, stone
Huarrles or supplies OF Stag are located
contains conclusions OF wide interest,
These conclusions, az quoted from the
official report, are as follows:
The study OF these roads would
seem TO warrant the Following conclu-
sions:
THAT the rollcd-bascd type, provid-
cd 1t Is properly placed and compacted
| IL suitable type FOR brick cOn.truc-