count. In earthmoving operations, travel can be
time-consuming. Suppose you are operating a
12-cubic-yard scraper. It will carry about a
15-cubic-yard heaped load. If you carry only a struck
(level) load of 12 cubic yards, you lose 3 cubic yards
of load each trip. To move 60 cubic yards takes five
trips when only 12 cubic yards are hauled each time.
Hauling full, heaped loads, you would move the same
amount of material in four trips. If your haul is short
and units are waiting to go into the cut, you can
increase production by taking only a good load
(somewhere between struck and heaped) and moving
out, rather than spending extra time obtaining a heaped
load.
On most construction jobs, both cuts and fills are
required. To increase job efficiency, plan your job so
that the material taken from a cut is used in a fill area.
This is known as balancing the material.
PIONEERING
Pioneering refers to the first working over of an
area that is overgrown or rough and making that area
accessible for the equipment needed for the project.
In pioneering, the operations of clearing,
stripping, grading, and drainage are all done
practically at the same time, rather than performed as
separate operations. A dozer starts out along a
predetermined route and leaves a road behind it. This
may be a haul road on which trucks and equipment
will use in later operations.
Suppose you, as a dozer operator, get the job of
cutting a road on the side of a mountain to be used for
access to a proposed airstrip or to reach a mountain
stream to be developed into a water supply system.
Where should you start and how should you proceed?
The route your mountain road is to follow will be
staked out by a survey party. You should start your
road at the highest point possible and let the force of
gravity help the dozer.
In clearing on sidehill cuts, brush and trees should
be cast far enough to the side of the road so that they
will not be covered with the earth. It is even better if
you can cast them over the edge with an angle blade
of the dozer when the road is cut. When cutting the
road, do not watch the grade stake immediately ahead
or you will find yourself below grade. Instead, watch
the third or fourth stake down.
NOTE: It is better to be above grade and come
back and cut down to grade than to be below grade and
have to come back and fill.
CLEARING
Clearing is a construction operation consisting of
cleaning a designated area of trees, timber, brush,
other vegetation, and rubbish; removing surface
boulders and other material embedded in the ground;
and disposing of all material cleared.
Clearing, grubbing, and stripping are different in
every climatic zone, because each has different types
of forests and vegetation. The nature of a forest can be
determined from records of the principal climatic
factors, including precipitation, humidity,
temperature, sunlight, and the direction of prevailing
winds. The types of forests can be generally classified
as temperate, rain, monsoon, or dry, according to the
climates in which they exist.
Clearing usually consists of pushing uprooted
trees, stumps, and brush in both directions from the
center of the area to be cleared. Clearing should be
accomplished so that debris (spoil material) is placed
in a designated spot with only one handling. In
clearing landing strips, for example, it is generally
necessary to dispose of material along each side of the
strip outside the construction site. If the site permits
burning, the haul distance can be reduced by piling
brush, stumps, and trees on the site and burning them.
Production in this field must be estimated, rather than
calculated.
GRUBBING
Grubbing consists of uprooting and removing
roots and stumps. In grubbing, stumps that are difficult
or impossible to pull out, even with winches, should
be burned or blasted. Your supervisor will decide the
method. If the stumps are to be removed by blasting,
a qualified blaster must be called upon to do the job.
If they are to be burned, you may be assigned the task.
Green stumps require continuous application of heat
before they catch fire. Check with your supervisor
about safety measures that should keep the fire from
getting out of control if you have to do any stump
burning. Remember that it may take as long as 3 or 4
days for a stump to burn out. Keep a check on the
burning during this period. If a project has a high
priority and time must be saved, stumps will probably
be blasted, rather than burned. When stumps have
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