Temperature Effect On the Modal Properties of Laminated Composite Structures

The composite materials and structures currently have a wide range of engineering applications, especially in aeronautical, ship and marine structures. The increasing use of composite materials in engineering structures has brought many new problems for structural maintenance, inspection and vibration control. Vibration damping becomes increasingly important for improvement of vibration and noise control, and fatigue and impact resistance in advanced engineering systems. The examination of environmental factors on structural vibration properties is important in order to reliably apply the vibration-based structural condition monitoring and vibration control techniques to engineering structures. Environmental conditions affect structural vibration properties in a complicated manner, so in this paper the variations of frequencies, mode shapes and damping with respect to temperature changes from -15 to 45 Celsius degree are investigated. The modal properties are identified from vibration tests of cantilever beams using Subspace-based System Identification (SSI) method.