Model updating of uncertain parameters of carbon/epoxy composite plates from experimental modal data

Abstract

This work presents a methodology to obtain physically-sound models of composite structure laminates using a combination of modal analysis, numerical modelling and parameter updating, avoiding the common uncertainties on the constructions of similar numerical models. Moreover this model establishes the baseline (pristine situation) of the dynamic behaviour of the set of composite plates. Therefore it could be applied for condition assessment or quality manufacturing control of existing structures through a nondestructive Structural Health Monitoring (SHM), and hence it could help to detect degradation or defects of the composite components. The driven data of the methodology were the modal frequencies and shapes of composite plates. To obtain these values an extensive experimental campaign of modal analysis has been performed on a set of carbon/epoxy laminates.A multiple input single output technique has been applied, using a roving hammer exciting the plates at evenly distributed Degrees of Freedom (DoF),

Model updating of uncertain parameters of carbon/epoxy composite plates using digital image correlation for full-field vibration measurement

“…The smaller dimension of the element will coincide with the thickness of each of the 21 plies or 32 plies of the plates, that is, 0.19 mm. Regarding the larger dimension, a sensitivity analysis was carried out with values of the element size between 25 and 2.5 mm [18].…”

“…Thus, in the next step, the model updating, only the numerical values of those parameters that are identified to be influential will be adjusted until the objective function is minimized. The sensitivity analysis performed in this work is explained in detail in [18]. It was demonstrated that the three parameters to which the model is more sensitive, are those presented in Table 5.…”

“…As a result of the whole process, a physically more accurate model is obtained on which discrepancies with the corresponding experimentally measured modal parameters are drastically reduced. Experimental results obtained from the first experimental method using a roving hammer and accelerometers, together with the consequent model updating, has been already presented in [18]. This paper is then focused on the modal analysis of data coming from DIC and the comparison of the results of the whole process obtained with the alternative experimental techniques.…”

An Improved Dynamic Model Updating Method for Multistage Gearbox Based on Surrogate Model and Sensitivity Analysis

“…The model updating is based on the experimental results, and the error between simulation and experimental results is minimized by adjusting the matrix or parameters appropriately to improve the model accuracy [4]. Currently, model updating methods are primarily categorized into direct updating and iterative updating [5].…”

Location effects on bend-twist coupling modes characteristic of the laminate plates

“…Murray 7 presented the experimental verification of a composite FEM by static bending tests of 500 mm ×200 mm BT coupled laminate plates, it was found that the bending and twisting response of samples were linear within the range of applied loads and the sensitivity of laminate thickness and accuracy of ply angles. Cuadrado 8 presented a methodology to obtain a physically more accurate model using experimentally measured modal parameters. Thai 9 illustrated a new tangent shear deformation theory for the static free vibration and buckling analysis of laminated composite and sandwich plates, a weak form for the plates based on ITSDT was derived and solved using isogeometric analysis.…”