Uncertainty quantification on elastic parameters of composite beams and its experimental verification

An uncertainty quantification method was proposed for the elastic modulus of heterogeneous composite beams based on limited experimental data samples, to quantitatively describe the dispersity of the macroscopic mechanical properties of composites. With the spectral decomposition model of the uncertain elastic modulus of beams, the uncertainty quantification was achieved by the Bayesian theory and the Monte Carlo simulation. Experimental tests were conducted on the composite beams from the same batch, the uncertainty quantification model was constructed by the samples of the elastic modulus of beams identified from the modal test data, and the measured dynamic response samples from vibration tests were adopted to verify the correctness of the quantification model. The method can construct an accurate quantification model for uncertain system parameters with a small sample of experimental data. It overcomes the drawback of traditional probabilistic models which require large sample data. The proposed method provides references for the uncertainty quantification analysis and reliability evaluation of composite structures. © 2018, Editorial Department of Journal of Southeast University. All right reserved.