What is kmod?

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 ons 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.
    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. (EN 1995-1-1 § 3.1.3).

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 > Mateiral library.

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