SIMPLIFIED METHOD FOR PREDICTION OF VIBRATION BEHAVIOR OF STEEL-CONCRETE COMPOSITE FLOOR SUBJECTED TO GENERAL LOADING

Abstract

Vibration serviceability problems have often been encountered in steel-concrete composite floors due to their long span and lightweight nature and have low damping depending on the occupancy. These are being used for various applications and hence are being subjected to different dynamic loads such as those due to human excitations and mechanical vibrations. Thus, it becomes necessary to predict the vibration behaviour at the design stage itself to avoid problematic floors. Previous researchers have extensively studied and presented simplified equations to understand the behaviour of floors subjected to human excitations such as walking, jumping, dancing, etc., but these equations are based on the beam mode of vibration. This paper presents a method that captures the behaviour of the floor alone subjected to a certain frequency and a general dynamic load. A novel displacement-controlled test to predict natural frequency was conducted in which the floor was subjected to vibration with a certain displacement over a range of forcing frequencies away from the natural frequency and the results conclude that the method shows good agreement with the traditional heel drop test and can be used for the purpose.