Plastic Hinges - CAESAR II - Reference Data

CAESAR II Applications Guide

Reference Data

The steps in setting up a plastic hinge are illustrated below. The leg from A to B is overheated, causing bending of the B-D support leg. This example models the plastic deformation at cross-section E-E. The plastic hinge is formed between nodes 10 and 15. The plastic hinge is modeled as a zero length expansion joint with rotational bi-linear restraints. The expansion joint is used to provide translational and torsional rigidity at the plastic hinge junction. Two bi-linear supports are used to model rigid resistance to bending until a breakaway force (yield force) is exceeded, at which point bending is essentially free.

The yield force is computed using the following equation:

Fy = SyZ(SF)


Sy is the yield stress

Z is the section modulus

SF is the safety factor