> For the complete documentation index, see [llms.txt](https://tlcfem.gitbook.io/suanpan-manual/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://tlcfem.gitbook.io/suanpan-manual/element/beam/f21h.md).

# F21H

2D Force Based Bernoulli Beam With Lumped End Hinges

* Number of Nodes: 2
* Number of DoFs: 3 (Translation, Translation, Rotation)
* DoF Label: U1, U2, UR3

## Syntax

```
element F21H (1) (2) (3) (4) [5] [6]
# (1) int, unique element tag
# (2) int, node i
# (3) int, node j
# (4) int, section tag
# [5] double, normalized length of each end hinge, default: 0.2
# [6] bool string, nonlinear geometry switch, default: false
```

## Remarks

1. The interior is assumed to be elastic so the response can be precomputed. For each end hinge, two integration points are used.
2. To use the corotational formulation for nonlinearity, please turn on the switch.
3. Unlike 3D beam elements, there is no need to attach an `orientation` to 2D beam elements.

## Output Type

This model supports the following additional history variables to be recorded.

| variable label | physical meaning          |
| -------------- | ------------------------- |
| BEAME          | local element deformation |
| BEAMS          | local element resistance  |

For example,

```
hdf5recorder (1) Element BEAME (2...)
hdf5recorder (1) Element BEAMS (2...)
# (1) int, unique recorder tag
# (2...) int, tags of elements to record
```


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