Submitted to: Ohio State University Thesis
Publication Type: Other
Publication Acceptance Date: 6/20/2002
Publication Date: 6/20/2002
Citation: Knueven, C.J. 2002. Grade control capability of a pull-behind plow under experimental conditions. Ohio State University Thesis.
Technical Abstract: The research objective was to test the grade control capability of the Liebrecht pull-behind plow. The plow's installation performance (i.e., grade control and deviations from grade) was compared to specifications in ASTM 449- 97 and selected other criteria. Field research was conducted at The Ohio State University's Don Scott airfield facility. The influence of four key factors was evaluated; speed of operation, depth of operation, grade change, and crossing extreme land surface changes. For the 1.3% grade - down slope travel direction treatment combination, the 3.2 km/h travel speed produced a significantly greater average deviation compared to the two lower speeds (1.6 and 2.4 km/h). For the shallow depth - upslope travel direction treatment combination, the 1.6 km/h travel speed produced a significantly smaller average deviation compared to the 2.4 km/h travel speed, but neither the 1.6 or 2.4 speeds were different from the 3.2 km/h speed. For the deep depth - down slope travel direction treatment combination, the 3.2 km/h travel speed again produced a significantly greater average deviation compared to the two lower speeds (1.6 and 2.4 km/h). Generally in these three specific cases, as speed increased the average deviations increased. Overall, there were no differences in average deviations when comparing the shallow depth range to the deep depth range. There was no significant difference between the treatment shallow depth at 0.1% grade, deep depth at 0.1 % grade, and 1.3% grade) within the 1.6 km/h level, but there were significant differences between treatments for the 2.4 and 3.2 km/h levels. Within the 2.4 km/h level, the average deviation for the 1.3% grade was significantly smaller than that of both the shallow and deep depths. Within the 3.2 km/h level, the average deviation for the deep depth was significantly larger than that for the shallow depth and the 1.3% grade. For the perpendicular approach to the extreme land surface changes, there was no difference in the average deviations between the four speeds. The angled runs were problematic because of extreme side-to-side tilting of the tractor, the plow, the laser grade control mast, and GeoStar mast. Within 44 experimental runs, there were 101 instances where the 2.5 cm criteria was either equaled or exceeded, and 48 instances where the 5.1 cm criteria was either equaled or exceeded.