section. This value is the total end area of the cross-sectional view.To compute the amount of cubic yards betweentwo cross sections, use the following equation:(A_{1 }+ A_{2}) x 1.85 x Distance= Cubic yardsA_{1 }= Area of one end cross sectionA_{2 }= Area of other end of cross section1.85 = Constant factorD = Distance between two end areas that must bechanged to a decimal form; for example, 250feet = 2.50, 125 feet= 1.25,75 feet= .75, andso forthTo compute the equation, take the area of one endsection (cross section) plus the area of the other endand multiply the sum of the two areas by a constantfactor of 1.85. This value should now be multiplied bythe distance between the two end areas to determinethe number of cubic yards. (See fig. 15-21.)CONSTRUCTION (GRADE) STAKESGrade work is the plotting of irregularities of theground (making cuts or fills) to a definite limit ofgrade (elevation) and alignment. This is performed byreading information placed on construction (grade)stakes.Figure 15-20.—Area of trapezoid.Figure 15-21.—Computing cubic yards of cross sections.15-15