Experimental modal analysis of the composite laminates with temperature variation

The effect of varying environmental conditions on the modal properties of composite laminates was studied by experimental tests,which is vital for the safety of vibration-based structural health monitoring(SHM) and vibration control techniques.The structure responses were measured with different temperature conditions by exciter and hammer tests.The modal parameters of composite laminates were identified by the Stochastic Subspace Identification(SSI) method.It is found that the frequencies and damping ratios have a strong negative correlation with temperature,but no clear correlation of mode shapes with temperature changes can be observed.These experimental test results indicate that the influence of temperature variation should be considered during the design process of structural health monitoring and vibration control techniques in laminated composite engineering systems.