> 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/truss/t2d2s.md).

# T2D2S

2D Linear Truss Using Section

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

## Syntax

```
element T2D2S (1) (2) (3) (4) [6] [7] [8]
# (1) int, unique element tag
# (2) int, node i
# (3) int, node j
# (4) int, section tag
# [5] bool string, nonlinear geometry switch, default: false
# [6] bool string, whether to use log strain, default: false
```

## Remarks

1. Compared to `T2D2`, `T2D2S` uses section instead of material. Hence, sectional area is handled by the corresponding section model.
2. The nonlinearity cannot propagate into the section level. So it is not possible to update area in `T2D2S`.


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