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Grid Method Earthwork Calculation

Use a grid to determine points of changes in cut and fill to interpolate total cut and fill for your disturbed area

create a grading plan, make sure it meets grade and specs
create a grid- preferably on a piece of grid paper (you may get confuse with too much on your grading plans)
remember for each point you will calculate the existing and the proposed elevations (make it easy on yourself and do not create too many grids)
- make sure your grid covers your disturbed area
- Label Each of your grids A B C D, according to how many blocks on the grid it intersects
Calculate the proposed and existing elevations of each intersection (see figure below)
- use your scale (to the scale of the drawing)
- measure the distance between the contours that are around your particular point on the grid- we will call this distance T
- Measure the distance from the contour directly up from your grid point- we will call this distance S
- Multiply S/T by contour interval then take this and subtracted by the value of the next contour up, giving you the elevation at the grid intersection
DO this for every intersection for both proposed and existing
Calculate your cut and Fill
- Existing - Proposed = -fill (negative) +cut(positive)
- Proposed- Existing= -cut(negative +fill(positive)
It may be beneficial to keep a table of your A, B, C, D's and whether they are cut or fill (otherwise you will only have a net volume for both cut and fill)

Now place your cut values in the following equation
Cut = Area of grid * [∑A+ 2∑B + 3∑C + 4∑D) / 4]
Fill = Area of grid * [∑A+ 2∑B + 3∑C + 4∑D) / 4]