Sensitivity of Natural Frequencies to Composite Effects in Reinforced Concrete Elements

During the last two decades, investigations on the dynamic properties of structural elements have been the subject of numerous research works. The primary reason for this is the awareness and interest in using dynamic testing techniques for the purposes of health monitoring and damage detection for engineering structures. The dynamic properties of any structural element are governed by the relationship of the material properties and the boundary conditions. For steel, the dynamic properties relate to steel element properties, which are assumed to be the same under different load conditions, and its boundary conditions. For concrete elements, such as plain concrete, the dynamic properties are related to the behavior of the concrete element, which will have different behaviors under different load conditions, and its boundary conditions. Reinforced concrete (RC) elements have a composite effect due to the presence of different materials to form the RC elements. Therefore, in order to simplify the modeling of the mechanical behavior ofRCelements, the boundary conditions are assumed to be the same under different conditions for the purpose of this present study