construction procedures

#3 The performance and retarder curves for a wheel tractor-scraper are shown in Figures 4-2 and 4-3. Using the average speed method, estimate the travel time for a tractor scraper whose hauls rated payload 4,000 ft. up a 5% grade from the cut to the fill and returns empty over the same route. The rolling resistance factor for the haul road is 120#/ton.[1 mi/h=88 ft/min] [Travel time = Distance/Speed] (Ans. :Haul time= 6.6 min and Return Time=1.7 min) #4 A power-shift crawler tractor is excavating loose common earth and pushing it a distance of 120 ft. Maximum reverse speed are: first range, 3 mph; second range, 5 mph; and third range, 8 mph. Rated Blade capacity is 11 LCY. Estimate dozer production if the job efficiency factor is 0.75. [Ans. 643 LCY/h)