Study of Nonlinear Fluid Viscous Dampers Behaviour in Seismic Steel Structures Design

For a seismic increased protection, new technologies have been developed, among these technologies there is the “passive energy dissipation devices”. The absorption of the seismic input energy in the buildings and reducing its damage are the main objectives of these devices. This study will focus on the seismic design of structures with supplemental fluid viscous dampers device. A 3D numerical investigation is done considering the seismic response of a twelve-storey steel building moment frame with diagonal FVD that have nonlinear force versus velocity behaviour. Fast nonlinear analysis of Boumerdes earthquake (Algeria, May 2003) is considered for analysis and calculation using SAP2000 software and comparisons between linear-, nonlinear-damped and unbraced structures are shown in a tabulated and graphical format. The results of the various alternatives studied were discussed and the conclusions showed the important contribution of nonlinear FVD to improve the dissipative capacities of the structure without increasing its stiffness in a significant way which contributes to reduce the quantity of steel necessary for its general stability.