Analysis of Damping Ratio in Passive Control Devices with Graded Sand as Fillers in the Shaft Section

Abstract

Earthquake resistant design of structures has become a necessity in the present. Various kinds of innovations have been found in making earthquake dampers which are attached to the building structure. This innovation is one of passive control systems that modify the mass and stiffness as well as by adding damping materials to control the dynamic response of the structure due to the influence of lateral forces, one of which is the seismic force. This study focuses on a passive control device that can be added to the structure, which is a composition of rubber layers and steel plates with graded sand as the centre filler. Several previous studies have proved that the rubber has the ability to reduce vibration because of its elasticity. While the sand as choice for additive material based on a grain of sand forms a uniform that cause internal friction between the sand and can produce damping. Research conducted on a passive control device without graded sand as the centre filler and a passive control device with graded sand as the centre filler by using the half power bandwidth method to produce a damping ratio value (ξ). The experimental results showed that the value of the damping ratio of the passive control device with graded sand as the centre filler increased up to 43.94% instead of the passive control device without graded sand as the centre filler.