Question

1. A small hydraulic backhoe excavator will be used to dig a trench (see the figure below) in hardclay. The excavator has a bucket of 3/4 cu yd. The maximum

digging depth of the excavator is 4 ft. The average swing angle is expected to be 90°. Estimate the hourly trench production in linear feet if job efficiency is 70%. Assume that the swell is 20%.

Fig: 1

Fig: 2

Fig: 3