EnginSoft - Conference Abstracts

EnginSoft Users' Meeting 2007
Le Tecnologie CAE nell'Industria

Identifying the Material Parameters for the Simulation of the failure of FRP

Baur Thomas - UAS Northwestern Swizerland
Fritsche Peter - UAS Northwestern Swizerland

Abstract

When the nonlinear behaviour of materials is simulated, very often the identification of the material parameters is an important and not very easy task that has to be done. This is especially the case with material that soften after reaching the maximum strength, as many fibre reinforced plastics do. This softening leads to the localization of the strains and is the reason for the simulation results to depend on the size of the elements. Therefore, before the material parameters can be identified, a method has to be found to overcome these problems.

In a previous work this has been accomplished. The usual material parameters as strength and Young's Modulus were identified with the usual tests. In contrast to this, the material parameters that govern the formation and the development of cracks have been identified by trial and error from specific tests. In the validation with a crash experiment, the results of the simulation with these parameter compared favourably with the experimental results.

In the upcoming work we will first identify these parameters in an optimal way using Mode Frontier. Then we plan to compare different ways of optimisation, starting with the "conservative" way as described above and than introducing more and more material parameters into the optimization procedure. We hope to get insight into the way the optimisation algorithm works and learn at the same time something about the physics of the problem at hand.