A Caterpillar D30D articulated dump truck has the rim pull curve in figure 1

A Caterpillar D30D articulated dump truck has the rim pull curve in figure 1. (Gross weight 21.9 t empty, 49.117 t loaded). If the truck ascends an 8% grade with a rolling resistance of 40 kg/t, find the following:
a) Total resistance (kg)
b) The required rim pull (kg) when loaded
c) The maximum speed of the truck when loaded (km/h)


A Caterpillar 631 E tractor scraper has the following characteristics:


Maximum heaped volume = 19.6 Bm3
Maximum payload = 34,000 kg
The material hauled is earth with a density of 1825 kg/Bm3
Rolling resistance is 60 kg/t and operating conditions are average with a job efficiency of 50 min/hour.
The haul route comprises of the following sections:
Section 1 (100m) level-loading zone
Section 2 (900m) 5% down grade
Section 3 (100m) level dumping zone
Section 4 (900m) 5% up grade
Section 5 (80m) level turnaround area.
Estimate the machines production under these conditions.