Variation of modal properties by combined effects of temperature and boundary condition

摘要

Changes in environmental conditions (such as temperature and humidity) and boundary conditions have been observed to have significant impact on structure's dynamic properties [1-6]. In general, environmental factors affect structures in a complicated manner such that it may result in support movement to strengthen or weaken the constraints [6]. Such changes of boundary conditions also can lead to significant variation of structure's modal properties. However, few studies have considered the existence of both temperature and boundary condition as the combined contributing factors in changing structure's dynamic properties. This paper proposes a numerical study to analyze structure's dynamic properties under combined influence of temperature and boundary condition. A beam finite element model that can consider the changes in both temperature and boundary condition is established. Numerical study is conducted to reveal the relationship between the variation of the beam's dynamic properties and the changes of its boundary condition as well as ambient temperature. The obtained conclusion will provide insights of the influence of these two factors on future dynamic based structural health monitoring studies.