> 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/templates/concrete-box-girder-bridge-workflow/substructure-cbg/bent-cbg/bent-cap-cbg.md).

# Bent Cap \[CBG]

The Bent Cap (integral bent) object models a transverse concrete bent cast integrally with a box girder at a support line. It takes its cross-section outline from the host box girder at that station, sets its thickness along the girder, assigns its material, and provides the rigid-link section used to connect supporting columns in the analysis model.

## Integral Bent

**Box Girder:** The Concrete Box Girder this bent is cast integrally with. Pick a single girder; this value is required. The bent inherits its cross-section outline and alignment from the selected girder at the support-line station.

**Support Line:** The support line that locates the bent along the girder. Pick a single support line; this value is required.

**Thickness:** Thickness of the bent cap measured along the girder (longitudinal direction), centered on the support line. Defaults to 150.

**Material:** The concrete material assigned to the bent cap, selected from the Materials defined in the Properties section. Drives the self-weight and quantity calculations.

**Transverse Offset:** Transverse offset of the bent cap relative to the girder centerline. Positive values shift the bent toward one side; leave at 0 to keep it centered on the girder.

## Referencing Objects

**Rectangular Pier Columns:** The Bent Column objects that frame into this bent cap (Read-only). This field is populated automatically as columns reference the bent.

## FEM

**Rigid Section:** Section used for the rigid links that connect the supporting columns and bearings to the bent in the analysis model. A value is required.

## Quantities

**Volume:** Computed concrete volume of the bent cap (Read-only; this is an expensive computation that may slow recompute).

**Weight:** Computed self-weight of the bent cap, derived from its volume and material density (Read-only; this is an expensive computation that may slow recompute).


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://docs.openbrim.org/templates/concrete-box-girder-bridge-workflow/substructure-cbg/bent-cbg/bent-cap-cbg.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.