NCEES Civil PE Specification Estimating Quantities and Costs: Work measurement and productivity
Problem
An excavator with a bucket capacity of 4 cubic yards (\(yd^3\)) follows a cycle that includes:
(a) Excavation time = 45 seconds,
(b) Two-way travel time = 5 minutes, and
(c) Transfer time to trucks = 30 seconds.
The excavator transfers the excavated material to a fleet of trucks transporting it offsite. The following data is provided:
- Overall efficiency factor for the excavator = 90%
- Truck capacity = 12 \(yd^3\)
- Truck cycle time (transfer + two-way travel + dumping) = 120 minutes
- Quantity of excavated material = 2,600 \(yd^3\) (loose)
To balance the production of the excavator, assuming 8-hr workdays, the number of trucks needed is most nearly:
Select an Answer:
