Page 197 - Moving the Earth_ The Workbook of Excavation

BASEMENTS

BASEMENTS 4.37

However the soil is moved, it should be spread in thin layers and thoroughly compacted by
rolling in open spaces, and tamping where rollers cannot reach. This will prevent serious mud dif-
ficulties during the work, possible damage to the retaining wall from pressure or fluid mud after
heavy rain, and excessive settling of the finished fill.
The average length of push is about 120 feet, very slightly downhill. This is within the eco-
nomical range of medium to large bulldozers, or small, self-loading scrapers, but help will be
needed from a loader or hand labor to cut out the south corners. The equipment should be small
enough to leave by the driveway when the job is done.
A dozer first cuts a shelf, level or sloping opposite to the hill at the top, just below the sidewalk.
This is done by digging along the edge line until a bladeful is obtained, then turning downhill, lift-
ing the blade at the same time, so that the fill is built higher than the cut to allow for compaction.
Scrapers can be used to cut down this shelf as soon as it is a few feet wider than they are, but a
dozer will be needed to keep the walls trimmed back to a vertical. The dozer can also cut much farther
into the corners than the scraper can, by the process of gouging and then swinging out.
The front-end loader can square the corners by working against one side, parallel to it, and dig-
ging into the bank until the other side of the corner is reached. The spoil is picked up, moved back,
and dumped in the path of the scrapers. Best work can be done if the corners are kept cut down
within a few feet of the level on which the scrapers are working.
The scrapers may be kept moving in a rotary path, as in Fig. 4.33, digging at the south end, and
dumping and spreading along the retaining wall. As the fill rises, it will enlarge to the south. At the same
time, a bulldozer can be working down the center section in the soil to be moved the shortest distance.
This dozer may also take care of trimming the fill for the scrapers and pushing it into the corners.
A self-powered tamping roller should be kept moving over the fill in both scraper and dozer
sections. Hand, gasoline, or air tampers should be used along the wall.
The parking lot fill, and that needed in the rear part of the driveway, cannot be placed on the
south side until the foundation of the building is in place. Material needed for this can be piled on
the edge, ready to be pushed in place.

FIGURE 4.33 Scraper digging.