Response Control of Structures Subjected to Multi-Hazards of Earthquake and Wind Using Base Isolators and Absorbers

Abstract

Short structures when they are designed using base isolation, dynamic wind effects may be more, and it may govern the design. This issue is taken care to some extent using Lead plug bearings. This puts the limits on effective seismic performance only for design basis or beyond. At lower seismic excitation levels, it may not be that effective. In view of this a suitable passive control system using the knowledge of isolators and absorbers is developed and analysed. Five storey shear building models with fixed base, base isolated separately supported on laminated rubber bearing (LRB), lead plug bearing (LPB) and isolated with LRB and install with tuned mass damper (TMD) are developed. These structures are numerically analysed considering six Indian earthquakes and dynamic wind load. TMD used in LRB supported building is provided in LPB supported building and responses of building models also observed under wind load which is more than design basis. Results of all cases are compared. Combined passive isolation along with absorber found suitable for multi-hazards like earthquakes where peak displacement increases by 0.76 times to 38 times, peak acceleration decreases by 73% to 99%, maximum inter-storey drift decreases by 71% to 99% when comparing with fixed base structure and for wind, values of peak displacement, peak acceleration, maximum inter-storey drift decreases by 45%, 46%, 44% when comparing with LRB provided structure.

Keywords

• structures
• earthquake load
• wind load
• isolators
• absorbers