- Enter the geometry of the structure as you would normally do.

If your model contains multiple independent structures, make one Diamonds-file for each structure. - Load group and masses
- Click on . Add a load group and select ‘Seismic’ from the list.
- To calculate the response of the structure due to the seismic load, the modal parameters of the structure (eigen modes and – frequencies) must be calculated by Diamonds. These model parameters depend on the stiffness and mass distribution of the structure.
- The stiffness is known by Diamonds. It is in the geometry of the structure.
- The mass distibution is related to the vertical loads (point loads, line loads, surface loads) (0,981kN -> 100kg).

The correlation coefficient φ multiplied by the combination factor Ψ_{2}(for EN 1990) will determine the masses.

For example: a life load of 5kN/m will lead to 5kN/m² x Ψ_{2 }x φ = 5kN/m x 0,3_{ }x 1 = 1,5kN/m of mass to be taken into account durign the model analysis.

- Define the seismic spectrum.

Read here how a seimic spectrum according to eurocode works (document is only available in Dutch at the moment).

Read here how to define a user defined Seismic spectrum. - Generate the combinations . Don’t forget to check the ULS SC combinations.
- Run the analysis . In the tab page ‘Dynamic’ choose ULS FC as reference combination.
- Run the reinforcement calculation , steel or timber design .

Diamonds will take the seismic combinations ULS SC into account. - Verify the deformations like you would normally do.