Safety第 94 / 110 题
A trench is 3 ft wide, 6 ft deep, and 40 ft long. How many cubic yards of spoil are generated (27 cubic feet per cubic yard), a figure needed to plan the 2 ft edge setback and haul-off?
a.8.9 yd^3
b.26.7 yd^3
c.17.8 yd^3
d.32.0 yd^3
解析
Volume = 3 x 6 x 40 = 720 ft^3, and 720 / 27 = 26.7 cubic yards of spoil. This volume determines how much material must be set back at least 2 ft from the edge or hauled away so its surcharge load does not collapse the wall. Underestimating spoil crowds the edge and endangers workers.
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