Page Comparison

h1. Arch bridges

A series of tips for modeling *arch bridges and soil interaction* are listed as follows:

* It may be useful to create and study a simplified model to gain insight into structural behavior.

* Creating a 2D model composed of [shell|kb:Shell] objects may then serve as a useful preliminary to the 3D model. A 2D model would represent a longitudinal section cut through the bridge and soil mass. This approach would reduce the model size and analysis time while providing the benefit of useful information and a comparison study.

* To most effectively model and [mesh|kb:Meshing] the 3D bridge structure, it may be best to use shell objects to draw the arch segments in the 2D elevation view, then extrude the shells into 3D [solids|kb:Solid] using Edit > Extrude > Extrude Areas to Solids.

* To prevent tension from developing in the arch and along the soil-structure interface, gap (compression-only) [link|kb:Link] objects may be used to model support points.

* [Nonlinear|kb:Nonlinear] [layered-shell|Layered shells] objects may be useful for 2D bridge models wherein which the arch or soil cannot carry tension.

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*Related Incident:*
* Incident 28827: [10/10/2010 email reply to the user with tips for modeling arch bridges|$5931241]
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h1. Arch system in 2D

To model an arch system in 2D, [shell|kb:Shell] objects should be used for plane stress problems, and [frame|kb:Frame] objects should be used for frame-type behavior. When using frame objects, a series of linear segments should be modeled to approximate the curvilinear profile of the arch.


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*Related Incident:*
* {incident:no=46447|comment=Arch}
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