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(1) Distributed ground displacements can be assigned to any pipe or frame object, but they will only have an effect only when distributed supports are also assigned to the same object.
(2) Distributed ground displacement loads assigned to a pipe will not impose any load on the pipe's discrete supports. If the user wishes to apply a matching point displacement load to a discrete support, such a load would need to be applied separately.
(3) When distributed supports are assigned to two adjacent pipes that share a common joint, distributed supports internally generate two sets of springs at a common joint. The first such set represent represents the last discrete support for the first pipe, and the second set represents the first discrete support for the second pipe. Distributed ground displacement loads are applied independently to each pipe, potentially resulting in a displacement discontinuity at the common joint. Such an a displacement discontinuity is acceptable and will be reflected in the analysis results.
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When distributed supports are assigned to a pipe or frame element, analysis model for the ground displacement loads is created as follows (see Figure 2):
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(3) Apply the ground displacement load to the fixed end of links that internally representing represent each discrete support.
Figure 2: Internal modeling of distributed ground displacements
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