> 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/material/material1d/elastic/multilinearelastic1d.md).

# MultilinearElastic1D

Uniaxial Multilinear Elastic Material

## Theory

A simple uniaxial multilinear elastic material model. The [`BilinearElastic1D`](/suanpan-manual/material/material1d/elastic/bilinearelastic1d.md) model is a special case of this model.

## Syntax

```
material MultilinearElastic1D (1) (2 3...) [4]
# (1) int, unique material tag
# (2) double, strain of the data point
# (3) double, stress of the data point
# [4] double, density, default: 0.0
```

## Usage

The first point does not need to be origin. Starting from the first non-zero point is fine. Multiple data points can be defined. A constant response is assumed after the last point.

```
material MultilinearElastic1D 1 1E-3 35 2E-3 40 3E-3 45 4E-3 30
```

![example one](https://1124082496-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FEquxr3H9WpPg4iPvT2mB%2Fuploads%2Fgit-blob-e564ad7cc80a9773c9ee7545536d859764b94379%2FMultilinearElastic1D.svg?alt=media)


---

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