A hydraulic shovel will be used to excavate sandy clay and load it into a 12 BCY dump truck. The shovel production at 100% efficiency is estimated to be 300 BCY/hour and job efficiency is 0.80. Truck travel time is estimated to be 8.0 minutes and truck fixed cycle time (excluding loading) is estimated to be 2.0 minutes. Equipment costs for the shovel and trucks are $40/h (shovel) and $20/h (truck). A. How many trucks are theoretically required to obtain maximum production? B. What is the expected production of the system in banked measure using this number of trucks? C. What is the expected unit loading and hauling costs in $/BCY?

A hydraulic shovel will be used to excavate sandy clay and load it into a 12 BCY dump truck. The shovel production at 100% efficiency is estimated to be 300 BCY/hour and job efficiency is 0.80. Truck travel time is estimated to be 8.0 minutes and truck fixed cycle time (excluding loading) is estimated to be 2.0 minutes. Equipment costs for the shovel and trucks are $40/h (shovel) and $20/h (truck). A. How many trucks are theoretically required to obtain maximum production? B. What is the expected production of the system in banked measure using this number of trucks? C. What is the expected unit loading and hauling costs in $/BCY?

Fundamentals Of Construction Estimating

4th Edition

ISBN:9781337399395

Author:Pratt, David J.

Publisher:Pratt, David J.

Chapter10: Pricing Excavation And Backfill

Section: Chapter Questions

Problem 7RQ

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