Earth whose in situ weight is 110 lb per cf and compacted weight is 124 lb per cf is placed ina a fill at rate of 280 cy per hr, measured as compacted earth. The thickness of the compacted layers is 8 in. A tractor pulls a towed sheepsfoot roller having drums, 6 ft wide. at a speed of 1.4 mph. 4 drum passes are specified for eack layer of earth. Assume a 50-min-hour effeciency.
How many square feet of compacted cy are placed per hour?
What area in square feet does the drum cover per hour?
How many drums are required to provide the necessary compaction?