Highway Earthwork Computations (Developed for Bendix G-15A Computer)

摘要

Three features of the Illinois program that are distinctive are (1) the method used for modifying roadbed coordinates, (2) the method used for locating slopestake points, and (3) the method used for determining a variable shrinkage factor. The coordinates of each point on the template are derived from the preceding point as points are taken in order from the centerline outward. A modification in pavement width or in another individual dimension will not change the basic formulae used to determine template coordinates. To facilitate mowing and to improve the appearance of the roadside it may be desirable to extend a slope beyond its intersection with the terrain nearest the ditch point where there is more than one intersection. The Illinois program accomplishes this by starting the slope-stake search with the point furthest to the left (or right) and working toward the centerline in finding points of intersection and in computing cut and fill areas. The shrinkage factor subroutine is based on a study of actual behavior of materials on highway projects in Illinois over a period of years. The formula developed allows for higher wastage and shrinkage in sections of relatively small size. (Author)