A level section has a formation width of 10 m, a side slope of 1: 2 (vertical: horizontal), and a central height of 2m. Determine the quantity of earthwork required for a 1 km length of formation (in m3).
Area of trapezoidal:
According to the trapezoid area formula, the area of a trapezoid is equal to half the product of the height and the sum of the two bases.
Area = ½ × (Sum of parallel sides) × (perpendicular distance between the parallel sides).
Average cross-sectional area(A) = ½ × (10 + 18) × 2