Page 166 - Moving the Earth_ The Workbook of Excavation

BASEMENTS

4.6 THE WORK

The upslope of the pile should be made according to the power and traction of the dozer, the
1
judgment of the operator, and may be between 1 on 5 and 1 on 2 ⁄ 2 . The easier gradients make it
possible to push larger loads, but they must be moved farther and require more ground space.
Lower Layers. After the digging has reached the half depth, the dozer should be moved out onto
the west bank and headed east along the south line of the excavation. An entrance ramp should be
started several feet back of the west line, as in Fig. 4.6(A), and a steep ramp cut down toward the
2-foot level. As the blade fills, the machine is swung toward the center of the hole, and the dirt is
left on its floor. The dozer returns to the south line, makes another cut, again swinging the spoil out
into the center, pushing it somewhat farther. It thus cuts out the full-width ramp by which the dozer
entered the pit from the south, and occasionally shifts to pushing the dirt obtained from the ramp
up on the north pile. As the east edge is approached, dirt may be pushed up on its bank, cutting a
ramp, instead of to the north.
The north slope may then be cut away in the same manner, the spoil first being pushed up the
undestroyed section of the ramp, as in (B), and finally onto the west bank. These cuts result in ver-
tical walls along the two long sides of the hole.
The inside ramps may also be removed by oblique passes from near the center (C), steering the
dozer so that the blade is parallel with the bank by the time it reaches it. The slope ahead of the
dozer can be gouged away in this manner, with the spoil being edged out into the open and pushed
up the west bank. With the west section of ramp removed, the dozer can be turned to cut away the
east part as in (D).

Finishing. After removal of the north and south slopes, the floor of the cut may be deepened by
pushing to east and west. These ramps up to original grade should have their lower ends at the
excavation line, and will therefore be cut back deeply into the bank, as in Fig. 4.7(A). Since a steep
ramp means less extra excavation, the slopes should be made as steep as practical. They may be
cut all the way through to begin with, for an easy gradient, and steepened as the hole deepens. The

FIGURE 4.6 Cutting lower layers.