Asphalt paving production and number of trucks required: Asphalt road paving pro
ID: 1709958 • Letter: A
Question
Asphalt paving production and number of trucks required: Asphalt road paving project is 3,000-ft long, 60-ft wide, and 6-inch thick. Other data follows: Asphalt rear-dump trucks are used for 20-ton hot-mix asphalt (HMA) load hauling from an asphalt plant to the paving site. (Truck cycle time is sum of loading time, hauling time, dumping/unloading time, and return time.) Maximum output capacity of the plant is 150 tons per hour and operating efficiency factor is 0.8. Most of the haul road is in good paved condition. Total haul distance is 5 miles (on average grade of + 1.25 % during haul). Each dump truck (empty weight 40,000 lb) is used at high tire pressure for transporting a full load of 20-ton. The dump trucks must keep the asphalt paver busy paving with adequate quantity of HMA to avoid cold joints. Paving capacity of the asphalt paver used for laying 12-ft wide lane (6-inch thick) is 40,000 lb at a paving production rate of 53 linear ft paved in 20-minutes assuming 60-minute hour efficiency, which is adequate to dump one truck load in the paver hopper and pave. The paved HMA has a typical unit weight of 145 lb/cft behind the paver. (a) Calculate the truck cycle time, number of trucks, and total number of truck trips for hauling plant-mixed HMA from the plant to the road construction project site. Use the following data: (b) Calculate the asphalt pavement production rate and total number of hours to complete the paving project.Explanation / Answer
Truck cycle time will be calculated as follows;
Truck cycle time = load time + haul time+ dump time + Return time
1. Load time = Excavator cycle time x No. of bucket loads
=0.13mins x 20 tons
=2.6 mins
2. Haul time = Haul distance / 88 x Haul speed
= 5 miles x (1.25%) / 88 x 0.8
=8.87
3. Return time = Return distance/ 88 x haul speed
= Same as that of haul time
4. Dump Time = As it largely depends on tye of hauling units
As per standards set by road councils it rear dump truck exceeds by 2 mins so let us consider as 3 mins
So, TRuck cycle time = 2.6 + 8.87 + 8.87 + 3 = 23.34 mins
2. Number of Trucks = Truck cycle time/ loader cycle time + 1
=23.34 / 2.6 + 1
= 9.97 which is 10 TRUCKS
3. Total number of truck trips = for 10 no. of truck trips would be 10 trips.
1. ASPHALT PRODUCTION PAVEMENT RATE =
=(Working min/hr / truck cycle time) x truck volume x no of trucks
= (60min/hr / 20) x 10 x10
=300 LCY/ hr.
2. NUMBER OF HOURS TO COMPLETE THE PROJECT = total cycle time + loads
=
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.