3.18 LoadData Section

The LoadData section is used to define load controllers. A load controller allows users to manipulate the value of most model parameters as an explicit or implicit function of time. A specific load controller is defined using the type attribute.

In order to make a model parameter time-dependent, first define a load controller in the LoadData section. Then, use the id attribute assigned to the load controller as the value of the lc attribute. For example, consider the following load controller was defined in the LoadData section.

<load_controller id="1" type="math">
    <math>2.0*sin(pi*t)</math>
</load_controller>

The id assigned to this load controller is 1. Then, this load controller can be used, for instance, in a boundary condition.

<bc type="prescribed displacement" node_set="set1">
  <dof>x</dof>
  <value lc="1">3.14</value>
  <relative>0</relative>
<bc>

The value parameter of this boundary condition is now made time dependent. Note that the actual value of this parameter will be the value of the load controller at a particular point in time, multiplied with the value specified by the tag's value (3.14 in the example).