Answer ALL Questions 1 Determine the maximum usable rimpull

Answer ALL Questions 1. Determine the maximum usable rimpull for a truck with a gross loaded weight of 48 tons traveling on dry hard clay loam having a coefficient of traction of 0.69. The load on the drive axle is 75,000 lb. Determine the required rimpull assuming that the loaded truck must move the load up a 6% grade and rolling resistance is found to be 3.5%. 2. Based on the conditions in question 1, calculate the total cycle time for the truck, assuming a maximum unloaded speed of 35 mph down the slope, a resulting speed factor of 0.75, and a hauling distance of 3 miles one way. The net weight of the truck is 37,500 lb. Assume 20 mph maximum speed in the loaded condition and an attainable speed factor of 0.65

Solution

Rimpull = [(weight of truck)*(grade of road )] + [(weight of truck) * rolling resistance

= 1/.69 *( 48*0.06 +48*0.035) = 6.609 tonn