# Plastic hinge formation in Liner element

**URL:** <https://forum.itascainternational.com/t/plastic-hinge-formation-in-liner-element/2360>\
**Category:** FLAC\
**Created:** [March 26, 2026, 8:39pm UTC](https://forum.itascainternational.com/t/plastic-hinge-formation-in-liner-element/2360 "2026-03-26T20:39:46Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Milads](https://avatars.discourse-cdn.com/v4/letter/m/ecccb3/32.png) [@Milads](https://forum.itascainternational.com/u/Milads)\
**Post date:** [March 26, 2026, 8:39pm UTC](https://forum.itascainternational.com/t/plastic-hinge-formation-in-liner-element/2360/1 "2026-03-26T20:39:46Z")

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I am modeling a sheet pile wall using liner elements in FLAC v9.6. Currently, I have assigned an elastic model to these elements, but I would like to know how to specify a plastic moment capacity so that a plastic hinge can form and the corresponding deformation will occur once that capacity is exceeded.

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**Author:** ![cheng](https://avatars.discourse-cdn.com/v4/letter/c/ecccb3/32.png) [@cheng](https://forum.itascainternational.com/u/cheng)\
**Post date:** [April 2, 2026, 7:18pm UTC](https://forum.itascainternational.com/t/plastic-hinge-formation-in-liner-element/2360/2 "2026-04-02T19:18:38Z")

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You might need to change the liner elastic constitutive model to an elastoplastic one, e,g, V-M model.  
An example how to set elastoplastic models for structure:

> **[Elastic-Plastic Plate (Collapse Load) with Uniform Lateral Load — Itasca...](https://docs.itascasoftware.com/itasca960/common/sel/test3d/Shell/CollapseLoads/CollapseLoads.html#collapseloads)**
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> Problem Statement