Structural Behavior of Building with First Level Height Variation Controlled by Viscous Fluid Damper

Abstract

The variation of height from one floor to another is associated with the decrease of stiffness. Such variations in the world, have claimed countless lives and have led to the collapse of structures throughout history, such as the earthquakes occurred in Loma Prieta 1989, Taiwan 1999, Northridge 1994, Ica 2007, several buildings products of the seismic event failed by the change of stiffness at the first level of the structure. The present research work analyses the structural behaviour of buildings in the first level height variation controlled by viscous fluid dissipators. Based on the analyzed investigations, we have noticed that the buildings of 3, 6, 9, 12, 15, 18, 21 floors, are structures that have collapsed in the described earthquakes, so on this basis we have analyzed the structuring of models with 900 m2 with the variation of the height of the first level in 3, 5, 7 m in the models of 3, 6, 9, 12, 15, 18, 21 floors correspondingly, in which we analysed the 21 models with a linear time-history analysis with 3 pairs of seismic records which were treated and scaled by using the SeismoSignal software, SeismoMatch, being the 1966 lima case 2 earthquake the predominant one to analyse the behaviour of the structure, in which we added the viscous fluid dissipators based on Fema 274 and the Hazus methodology, in which we could appreciate the parameters of drifts, accelerations, energy dissipation, hysteretic graph, which were obtained through the use of the ETABS 20 software. We conclude that the addition of viscous fluid dissipators improves the structural behaviour, optimally reducing the stresses in the building, controlling the height variation of the first level, which is

ideal for existing structures that require structural reinforcement, being the maximum tolerable drift of 0.009249 to ensure the proper functioning of this device, and it was also obtained that increasing the height in a new building is not appropriate because it increases the drifts and reduces the accelerations correspondingly.