Design Memorandum

TO:                  All Design Section Staff

FROM:            Bijan Khaleghi
DATE:             May 16, 2008
SUBJECT:       Computer Generated Design Calculations

Computer-generated design calculations may be used instead of longhand calculations. The calculation sheets shall be formatted similar to WSDOT STD calculation sheets for longhand designs. The header for electronic calculation sheets shall carry WSDOT logo along with project name, S.R. number, designer and checkerís name, date, supervising engineer, and sheet numbers. All computer-generated or longhand design calculations shall be initialed by the designer and checker. Checkerís initial may not be necessary if separate check calculations are provided. Output from commercial software shall be integrated into design calculations with a cover sheet that includes the WSDOT logo along with project name, S.R. number, designer and checker's name, date, supervising engineer, and a sheet number.

Consultant submitted design calculations shall comply with the above requirements, and shall carry structural stamp of the supervising engineer on the title sheet.

A sample calculation sheet for using MathCAD or Excel is attached for guidance. These templates could be modified for larger prints, adjusting cell width or other reasons. Code and other references used in developing calculations shall be specified. In general, when using Excel spreadsheet, enough information and equations shall be provided/shown in the spreadsheet so that an independent checker can follow the calculations.

To download the Excel file or the MathCad template, right-click on the file name and select "Save Target As..."

Excel file  05-2008.xlt
MathCad template  05-2008.xmcd


This memorandum is to further reinforce WSDOT QA/OC policy and to establish uniformity between computer-generated and longhand design calculations.

If you have any questions regarding these issues, please contact Eric Ferluga at 705-7179, J.C. Hsieh at 705-7215, or Bijan Khaleghi at 705-7181.

cc:   Mohammad Sheikhizadeh, Bridge Construction - 47354

       F. Posner, Bridge and Structures Ė 47340