Earthwork Area Calculation – Section – Summary
Area Calculation Comparison Table
Methods |
Formula |
Advantages |
Disadvantages |
| Trapezoidal method | Formula for triangle = ½ * Base * HeightArea of trapezoid = ½ * a * (b1 + b2) / 2 | Mathematically correct as all the calculations are done with pure triangle area and trapezoid methodDirect and involves less calculation | Difficult as it involves finding intersection point |
| Nett Area method | Area of Trapezoid(½ * a * (b1 + b2) / 2 | Depends upon only one formula trapezoid and hence it is simple compared to Trapezoidal methodMathematically correct as all the calculations are done with pure trapezoid method | Difficult as it involves finding intersection pointInvolves more calculations compared to Trapezoidal method |
| Simpsons 1/3 rd rule | Area = Interval/3 * [First value+ Last Value+4(Sum of odd n of y)+2(sum of even n of y)] | Produces more accurate results, as instead of connecting 2 adjacent points merely by a straight line, a parabola is chosenInvolves less calculation | Not practically usable as it expects the data to follow the rules below:
In case of even number of levels, for the last segment, a different calculation method needs to be adopted |
Section – Simpsons 1/3rd Rule Volume Calculation for Areas found using Section Method
