In the dialogue 
you specify whether the (sub) load case(s) are:
Subloadcases
- Periodic (the wave repeats in time) or not (=aperiodic wave):
Periodic
Aperiodic
- synchronous or not.
If there are no sub-load cases, only the periodicity applies. In case there are sub load cases in the dynamic load case, the synchronization is also important. This option is only relevant is the sub load cases are applied always together . If the sub load cases are working separately this option has no meaning. In case the sub loads work together and they are defined as ‘asynchronously’, Diamonds will find the most unfavourable situation (in this case period) between the sub load waves. If you choose ‘synchronously’, you need to know the time frame between the sub load waves and this needs to be constant. If you do not know the time frame between the sub load waves, or it does not remain constant, it is better to choose ‘asynchronously’.
Period
Next, you enter the period of the wave. In case of sub load cases, you need to enter the maximum period of all sub load waves. You can define the period in 2 ways:
- As an absolute value of the period(s) or the pulsation (rad/s)
On entering one of both, the other one is automatically calculated. - Relatively with respect to a chosen eigen period.
The period factor allows you to multiply the chosen eigen period with a value. The meaning here is that you can see the effect of a loading with a period close to (or equal) to the eigen period. You expect for this resonance of the structure, taking into account the damping of course.
Advanced
If you click ‘Advanced’, you will find following options:
- ‘# points’ is the number of points for which the displacements as a result of the loads per eigen mode are determined (= solving the kinematic equations). 100 points is a good choice.
- The larger the eigen frequency of a mode, the smaller the eigen period. To have also sufficient number of integration points for this kind of modes, you can specify a minimum number of points per wave. 15 is a good number.
- ‘# evaluation points’ is the number of points where the response is calculated by means of super position. Having set ‘# evaluation points’ and ‘#points’ equal is the most accurate, but will take up the most time. You can set ‘# evaluation points’ less than ‘# points’, the mistake will be negligible. There is no point in setting ‘# evaluation points’ higher than ‘# points’.
- If the sum of the effective modal masses is too small for one or more directions, you can proceed as follows:
- Either you redo the modal analysis requesting more eigen modes.
- Either you use the quasi static correction.
On the right side of the window you get an overview of all defined waves in the (sub) load case(s). Initially, when there are no waves defined yet, this graph will be empty. Later on, when you have defined all waves and you return to this window, you will see the combination of the defined waves. The active sub load case will be in bold.
