Dynamic Analysis and Vibrations Research on Multi-Degree of Freedom Shear Structures

Abstract

Abstract Vibration is everywhere in of our daily life. This paper studies the effect of rectangular pulse and free vibration on multi-degree of freedom systems. An undamped three-floor shear frame structure subjected to rectangular pulse and a damping three-floor shear building considered free vibration is investigated with respect to natural frequencies, mode shapes, and displacements of each floor level. This paper assumes the three-story shear building structure discussed has orthogonal damping, and the fundamental frequency will not change over time, which means that the mode shape of the system does also not change with time. In addition, the modal superposition method and Duhamel integrals are useful to study the response of the various vibration systems. In this work, it can be concluded that the main response is due to the vibrations’ first mode, even though all its mode shapes can lead to free vibration response. For amplitude of the motion, it will change with the frequency of excitation. When the non-periodic impulse is applied, the forced vibration will be different in the short duration of the impulse with the free vibration phase.