> For the complete documentation index, see [llms.txt](https://docs.openbrim.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.openbrim.org/examples/penndot-bridge-examples/penndot-refined-analysis-approval-workflow/lfd-straight-steel-i-girder-bridge-with-90-degree-skew-penndot-1.md).

# LFD Straight Steel I Girder Bridge with 90 Degree Skew \[PennDOT -1]

[LFD%20-%20Straight%20Steel%20I%20Girder%20Bridge%20with%2090%20Degree%20Skew\_R4.pdf](https://openbrim.atlassian.net/wiki/spaces/OBrIM/pages/2234580993/LFD+Straight+Steel+I+Girder+Bridge+with+90+Degree+Skew+PennDOT+-1?preview=%2F2234580993%2F2234679310%2FLFD+-+Straight+Steel+I+Girder+Bridge+with+90+Degree+Skew_R4.pdf)

The representative bridge is a straight two-lane plate girder bridge with identical four-girder cross-sections, and features continuous three spans over span lengths of 80, 100, and 80-feet along the control centerline. In this example, I-girders are modeled using a combination of member and shell elements for refined modeling. The top flange girder is connected to the deck with rigid elements, and the bridge deck is modeled using shell elements. Modular ratios of “n” and “3n” are used for the deck slab in calculating girder stiffness and modeled as time-dependent material property.

![](https://openbrim.atlassian.net/wiki/download/attachments/2234580993/image2019-6-26_23-54-59.png%3Fversion=1\&modificationDate=1561607698447\&cacheVersion=1\&api=v2)

![](https://openbrim.atlassian.net/wiki/download/attachments/2234580993/image2019-6-26_23-53-45.png%3Fversion=1\&modificationDate=1561607624966\&cacheVersion=1\&api=v2)

![](https://openbrim.atlassian.net/wiki/download/attachments/2234580993/image2019-6-26_23-53-55.png%3Fversion=1\&modificationDate=1561607635632\&cacheVersion=1\&api=v2)

![](https://openbrim.atlassian.net/wiki/download/attachments/2234580993/image2019-6-26_23-54-9.png%3Fversion=1\&modificationDate=1561607648581\&cacheVersion=1\&api=v2)


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