, 1917-08-30

to destroy 1t, and to counterbalance
the effects of these deteriorating infiu-
ences 1t is necessary to institute some
system of maintenance. There are
two common ways of maintaining a
road. One is to make periodic repairs
or renewals after sections of the road
have been practically destroyed; the
other is to employ n system of contin-
uous maintenance under which all in
juries to the roa are repaired as fast
as they occur. For earth, sand and
gravel roads the system of continuous
maintenance Is much preferable from
practically every standpoint, and that
system alone will be discussed here.
Road Drag.
The road drag is n simple and mex
pensive device for maintaining certain
types of roads which, when wet, be-
come rutted under traffic but which
become firm on drying out. 1t is use
full also in producing a smooth and
uniform surface IN newly constructed
roads of earth, earthly gravel, or any
similar material. The accompanying
illustration shows a typical design for
n road drag made of sawed timber.
Properly used at the right time the
drag performs four distinct functions:
first, by moving at an angle with the
travelled way, it tends to produce or
preserve n crowned cross section sec
ond, If used when the surface is COM
paratively soft, 1t tends to reduce ir-
Irregularities in the road, by moving
material from points which are rela-
%{-oJu bIOh to thnCa rrhinh ara raIo-
lively low; third, when used after q
rain 1t accelerates the drying out of
the road by spreading out puddles of
water and thus exposing n greater area
to evaporation; fourth, If the surface
material is in n slightly plastic state,
dragging smears over and partially
seals the so-called pores which natural
ly occur in earthly material, and thus
makes the road surface more nearly
tmpervious to water.
To obtain the best results dragging
should be done only when the surface
of the road is sufficiently moist for
the material moved by the drag to COM
pact readily after 1t Is moved, but not
Sufficiently wet for traffic following the
drag to produce mud.
The principal factor in successfully
operating a properly constructed road
drag, provided the condition of the
road is favorable, is skill on the part
of the operator. Such skill can be OBJ
tanned only by intelligent experience,
and no rules can be laid down which
would enable an inexperienced opera
tor to produce first-class results.
Under ordinary circumstances the
position of the hitching link on the
draw chain should be such that the
runners will make an angle of 60 to rs
degrees with the center line of the
road, or, in other words, a skew angle
of from Is to 80 degrees. But when
dragging Immediately over the ruts,
or down the center of the road after
the sides have been dragged, 1t may
be found advantageous to place the
hitching link at the center of the chain
and run the drag without skew. An in
telligent operator will learn quickly to
adjust such details as this, as well
as to shift his weight while riding
upon the drag in order to make 1t cut
where cutting is desirable, and depos-
II material where material is needed.
Making Repairs.
If roads of such types as have beer
discussed are to be maintained prop
erly, they must frequently receive 9TH
er attention than mere dragging. The
side bitches should be kept open and
free from vegetation, the cross drains
and culyerts maintained in proper con-
dition, and worn places in the surface
repaired as fast as they develop.
The material used in repairing the
surface should be the same as that
composing the surface and should be
put on In such quantity and
that after 1t is compacted the surface
will be uniform and continuous. Much
time and labor car be saved by max
ing repairs as soon as needed. because
when n bad place once develops in a
road 1t generally will spread very rap
idly until proper steps are taken to
correct 1t.
Cost of Maintenance.
There are not sufficient cost data
available at present to warrant any
very definite statements as to cost OF
maintenance, but when roads can be
maintained largely by use of the drag,
ms usually is the case with the sim
pier types of construction, the cost
ordinarily is very small. Accurate
data kept by a representative of the
Office of public roads for road main
tenance in Bennington county, Yer
mont, during 1912 and 1913 showed
that under favorable conditions u road
could be dragged at the rate of about
l mile per hour. This was where the
road was comparatively well shaped