The ULS Design Functions spreadsheet (last updated here) has had another update (2.09) to fix a problem when bars in different layers had different E values. The new version assigns the correct E and strain at yield to each layer.
The new version can be downloaded from:
Results for circular or cylindrical sections designed to Eurocode2 can be checked using the calculator at a new site, EurocodeApplied, which has detailed examples of analysis and use of various Eurocodes. Results for a circular section with an axial load of 2000 kN are shown below (click on images for larger view):
The results include detailed numerical output, optionally an interaction diagram (Moment capacity plotted against axial loads), and a detailed description of the analysis procedure, with reference to the relevant code clauses.
There are small differences in the results because:
- The on-line calculation uses the parabolic-linear stress block, whereas the spreadsheet uses the rectangular stress block.
- The on-line calculation uses a much greater number of layers to represent the circular section than the spreadsheet.
The Circu function in the RC Design Functions spreadsheet has an option to use the parabolic-linear stress block, and uses an analysis of the actual circular shape, rather than subdividing into trapezoidal layers, and gives near exact agreement with the on-line results. An example will be provided in a few days.