Timber design – BuildSoft Support https://support.buildsoft.eu BuildSoft Support Wed, 12 Aug 2026 15:06:52 +0000 en-US hourly 1 https://wordpress.org/?v=6.2.14 Can Diamonds calculate the buckling resistance of a wall? https://support.buildsoft.eu/knowledge-base/can-diamonds-calculate-the-buckling-resistance-of-a-wall/ Wed, 24 Nov 2021 13:58:24 +0000 https://buildsoftsupport.com/?post_type=ht_kb&p=6928 Unfortunatly, none of our programs is capable of calculating the buckling resistance of walls automatically.

However, you can manually verify the buckling resistance by modelling the wall as a column with height H equal to 1m and width B equal to the wall thickeness.

]]> How to do timber design https://support.buildsoft.eu/knowledge-base/how-to-do-a-timber-verification/ Mon, 07 Jan 2019 09:57:28 +0000 http://buildsoftsupport.com/?post_type=ht_kb&p=3445 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 kmod.
  • 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.
]]> What is kdef (creep timber)? https://support.buildsoft.eu/knowledge-base/what-is-kdef/ Wed, 28 Jun 2017 13:29:18 +0000 http://buildsoftsupport.com/?post_type=ht_kb&p=1282 The stiffness properties of timber depend on the timber type (solid, glued, …) and the climatic conditions (temperature, moisture variations). The effect is taken into account by the factor kdef.

According to Eurocode

  • Values for kdef are given in EN 1995-1-1 Table 3.2.
  • kdef is used to calculate the final mean values of the stiffness properties according to EN 1995-1-1 §2.4.1.
Design values Mean values Final mean values

    \[ E_d=\frac{E_m_e_a_n}{\gamma_m} \]

    \[ E_m_e_a_n \]

    \[ E_m_e_a_n_._f_i_n=\frac{E_m_e_a_n}{1+\Psi_2 k_d_e_f} \]

    \[ G_d=\frac{G_m_e_a_n}{\gamma_m} \]

    \[ G_m_e_a_n \]

    \[ G_m_e_a_n_._f_i_n=\frac{G_m_e_a_n}{1+\Psi_2 k_d_e_f} \]

 

In Diamonds

  • The values for kdef are implemented in the material library of Diamonds.

  • When you check the option ‘Take creep into account’ after clicking , the final mean value for Young’s modulus E_m_e_a_n_._f_i_n will be used. \Psi_2 is set equal to 1.

 

Note: PowerFrame cannot take kdef into account. Only Diamonds can.

]]> What is kmod? https://support.buildsoft.eu/knowledge-base/what-is-kmod/ Wed, 28 Jun 2017 13:29:16 +0000 http://buildsoftsupport.com/?post_type=ht_kb&p=1274 The strength properties of timber depend on

  • the timber type (solid, glued, …)
  • the load duration time (dead load is always present, wind loads are present for a shorter time, creep)
  • and the climatic conditions (temperature, moisture variations).

The effect of these three parameter on the strength properties, is taken into account by the factor kmod.

According to Eurocode

  • Values for kmod can be found in EN 1995-1-1 Table 3.1.
  • kmod will adjust the material properties in the design of timber structures.

In Diamonds

  • The values for kmod are implemented in the material library of Diamonds.
  • The service class (also called ‘Climate class’) to determine the value of kmod, can be imposed in the Load group dialog .
  • Where a load combination consists of actions belonging to different load duration classes, the value of kmod should correspond to the action with the shortest duration (EN 1995-1-1 § 3.1.3).
    For example: for a combination of dead load and medium term load, a value of kmod corresponding with the medium-term load should be used.

Note: it is not possible to impose a climate class in PowerFrame. Each timber-quality has one kmod assigned, which will be used for all combinations. The value for kmod can be viewed/changed with Edit > Material library.

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