Calculation Formulas

Area Calculations

Proration Example:
Pipe plan = 40 LFT
Pipe field measure = 45 LF
Structure Excavation plan = 120 CUYD
45 ÷ 40 = 1.125 x 120 = 135 CUYD new quantity for structure excavation

Volume Calculations

The below calculations are only used when weights (computerized load tickets) cannot be obtained for an item paid by the ton.

Cubic Yards
Unit Weight* = Pounds per Cubic Foot
Pounds per Cubic Foot X 27 = Pounds Per Cubic Yards
Length’ X Width’ X Depth’/27 = Cubic Yards
Cubic Yards X Pounds per Cubic Yards = Pounds
Pounds/2000 = Tons

Cubic Foot
Unit Weight* = Pounds per Cubic Foot
Length’ X Width’ X Depth’ = Cubic Feet
Cubic Feet X Pounds per Cubic Foot = Pounds
Pounds/2000= Tons

*Unit Weight is based on theoretical or the actual unit weight for the material being placed.

040-034 Calculation Sheet

Calculations made for determining pay quantities for contract items requiring computations too extensive to place in the Mobile Inspector report Postings Comments or in an AWP DWR Postings Comments field will be made on a 040-034 Calculation Sheet. These sheets can be attached to the Mobile Inspector Posting or the DWR Posting. Refer to Entering Reports, Postings, Attachments in the Mobile Inspector User Guide or to Adding a DWR, Postings Tab, Item posting attachments in the AWP Construction User Guide for details. They are also saved to the Contract Files\Contract\07 Estimates\7.X Calc Sheets directory. Name these sheets using this standard naming convention; YYYY-MM-DD.DWR.inspector initials (e.g. 2024-08-11.DWR.JS.pdf, 2025-08.06.DWR.JS.jpg).