Solve

Open ended Q&A. 7. Consider a mine where a 50 ton, articulated rear dump truck hauls ore from the underground to the surface. Ore is loaded in the truck by a 6.1 m3, remote LHD near the entrance of the stope. The truck hauls the ore 550 m along a nearly level drift, then up a 1450 m long decline at 10% gradient to the surface. Once on the surface, the truck travels another 200 m to the mill, where the ore is dumped into a crusher feed bin. Estimate the time for this haul road profile giving that the truck speed is as follows: . Up a 10% gradient decline, loaded @ 10 km/hour, . Over a level gradient, loaded @ 20 km/hour, . Over a level gradient empty @ 30 km/hour, and . Down a 10% gradient decline, empty @ 20 km/hour