Feasibility of using Large Tractor Dozers in the Surface Mining of Coal and the Reclamation of Mined Areas,

Three tracked and three wheeled larger dozers concepts were evaluated to determine their potential for earthmoving, based on the earthmoving rates and owning and oeprating costs of existing dozers. The concepts evaluated were in the 1250- to 5000-horsepower range. For equal operating conditions, using tractor dozers in the 3500- to 5000- horsepower range could increase the earthmoving rates by an estimated 500 over those of currently available dozers in the 500- to 700-horsepower range, and the larger dozer concepts could reduce the earthmoving costs to about 0.015 per loose cubic yard from about 0.02 per loose cubic yard for currently available dozers. Large tracked dozers could be built with the same average ground contact pressures as currently available tracked dozers, which would give them an advantage over equally large wheeled dozers on soil conditions less than optimum for compaction. Four appendices cover the following topics 1 Terrain data collection procedures and data on strip-mined areas in four different geographical areas in the United States 2 Vehicle characteristics required for the Army Mobility Model and pertinent characteristics of the dozers evaluated in this study 3 Scaling laws for a dozer blade optimization study and 4 Examples of how to apply dozer earthmoving rates and costs to two hypothetical reclamation projects.