×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Grading By Hand Equation

Grading By Hand Equation

Grading By Hand Equation

(OP)
I had someone show me a matrix system to grade a site by hand.  It involved taking the four corners of each box averaging them and then adding them all together.  A positive meant you had export and a negative meant you had import.  Let's assume we had 20'x20' grid boxes and the four corners are 2, 4, 6, 8.  The average of those numbers is 5.  Once you have that I can't remember the formula.  It was something like 5(20*20).  Then you do the next box and add it to the first and so on.

RE: Grading By Hand Equation

If you are talking about calculating a volume, the equation is Length x Width x Height.  In this case, the length and width would be 20 and the height (depth) would be your average cut/fill.  So, if you have an average cut/fill of 5 and an area of 400 (20 x 20), you would have a volume of 2000 (400 x 5).  Then you would add all of them up.  Make sure to keep your cuts negative and fills positive.

RE: Grading By Hand Equation

Four Point Method (Eng Units):

Vc = L^2 x (Hc)^2 / 108 x (Hc + Hf)

Vf = L^2 x (Hf)^2 / 108 x (Hc + Hf)

Where:
Vc = Vol Cut (CY)
Vf = Vol Fill (CY)
Hc = Sum of cuts on all four corners of grid
Hf = Sum of fills on all four corners of grid
L = Length of side of grid (feet)
108 CY = factor to convert to CY

This will result in Cut & Fill for each grid.

Example:

C = 1              F = 2
   ---------------
   |             |
   |             |
   |             |
   |             |
   ---------------
C = 2               F = 3

Hc = 3, Hf = 5

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources