> 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/eb21.md).

# EB21

2D Elastic Bernoulli Beam

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

## Syntax

```
element EB21 (1) (2) (3) (4) (5) (6) [7]
# (1) int, unique element tag
# (2) int, node i
# (3) int, node j
# (4) double, area
# (5) double, moment inertia
# (6) int, material tag
# [7] bool string, nonlinear geometry switch, default: false
```

## Remarks

1. No matter what material model is used, only the initial stiffness is used for computation since `EB21` is an elastic beam element.
2. Unlike 3D beam elements, there is no need to attach an `orientation` to 2D beam elements.


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