How to do timber design

To assess a structure (whether it is sufficiant or not), the following steps must be followed in sequence:

• Schematising the construction
• Determining the internal forces and moments (= global analysis)
• Checking the cross-sections (= design):
  • Strength
  • Stability 
  • Stiffness

In Diamonds

• In the Load groups dialog , define the correct Service class.
  The Service class is required to determine k_mod.
  
• Calculate the internal forces (syn. global analysis) F9 or .
  Decide whether global imperfections are necessary or not.
  Check the option to take the creep into account (more info). 
• Set the buckling lengths.
  Don’t skip this step! Without the correct buckling lengths the stability results have no meaning.
• Select the correct timber standard using the menu Analysis > Timber standard.
  A list with all available standards in Diamonds can be found here.
• Click on F3 or to start the verification (more info).
  The verification is supported for:
  • constant cross-sections with shapes: 
  • variable cross-sections with shape: 

  At the moment it is not possible to do a timber verification on H-shaped cross sections or composed cross-sections (Section Utility).

• To view the results, go to the results configuration .
• Click on .
  The results of the strength check are behing the button , for those of the stability check click.
  The results of the strength and stability check are displayed as a percentage:
  • A structure is sufficient for strength, if the percentage is less than 100% for all bars.
  • A structure is sufficient for stability, if the percentage is less than 100% for all bars.

  Based on the percentage no judgment can be made on the extent to which a section is sufficient or not. This is because the used formulas are not always linear.

• Optionally, optimize the cross-sections.
  You can use the Optimization-function for this , but it might take a few iterations (and thus time).
  We recommend that you change the cross-sections manually to one (or more) size(s) bigger/smaller depending on the result you had then recalculating the model. Exspecially for experienced engineer, this works faster than the Optimization function.
• Don’t forget to verify the stiffness! Thus the vertical and horizontal deformation.
  Diamonds can calculate the relative deformation, but it’s still up to you to verify it.
  A structure is sufficient if the strength, stability and stiffness are sufficient.