Please note that mixed modeling is specific to bridge modeler files linked either to SAP2000 releases through version 14, or to the non-parametric modeling interface of CSiBridge.

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Mixed models

A mixed model is a computational bridge model where design contributions from both the parametric bridge modeler, and the non-parametric modeling interface of SAP2000 or CSiBridge, coexist within a single file. Mixed models are typically generated in the bridge modeler, then, once all relevant parametric features have been used, enhanced in the standard, non-parametric interface. Such a model is said to be linked between parametric and standard control platforms.

Users should note that work done through the bridge modeler updates when the model is linked. This may cause unexpected changes to connectivity between objects within the model, such as with bent location and the meshing between components defined parametrically and manually. Users should therefore update the linked model only after modeling is finalized. Another suggestion is saving a copy of the bridge-modeler file before linking.

Users may also develop bridge modeler and non-parametric models in separate files before merging them prior to analysis. This will prevent connectivity issues from arising during update. A customized bent not available through the bridge modeler serves as an example. In this case, a bent similar to the component desired may be modeled from a selection within the bridge modeler. Results may then be generated through preliminary analysis. Once customized components are manually designed in SAP2000 or CSiBridge, bridge-modeler bents are removed from the parametric model, and the models are then merged into a single file. Connectivity between bridge modeler and non-parametric objects is then defined manually before final analysis.

Purpose of mixed modeling

Mixed modeling is typically used to apply specialized features not available through the bridge modeler. Some examples may include the following:

  • Specialized bent connections
  • Explicit modeling of bridge foundation systems (piers, piles, pile caps, distributed soil springs, etc.)
  • Custom bearing layout (default configuration is one bearing under each web)
  • Specialized loading conditions (breaking forces, support settlement, etc.)

See also