APPLICATION OF AN IMPROVED MODEL FOR THE IDENTIFICATION OF MATERIAL PARAMETERS

Elastic material constants of thick plates can be identified by combining a range of measured natural frequencies with an accurate numerical model for the theoretical predictions. To deal with thick plates, a model that takes transverse shear effects into account is necessary. Since modeling errors affect the estimates in a systematic way, an accurate numerical model is of primary importance. Compared to a model used previously, an improved, more accurate plain model is studied here for the purpose of identification. This new advanced model is used to assess the systematic errors in the identification associated with the previous model It is shown that due to the errors in the previous model, the transverse shear moduli were overestimated, whereas the in-plane parameters were practically unaffected. The new model is implemented in the identification procedure whereby systematic errors have been significantly reduced. Experimental results are presented that support the theoretical investigations. Parameter...

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