VIBRATION CONTROL OF BUILDINGS ON HILL SLOPES

Abstract

Failure of buildings with open ground storey under earthquake excitation is a matter of interest of structural engineering. Generally open ground storey in the buildings used for parking purposes in the multistorey buildings. Absence of masonry in ll makes open ground storey relatively soft or exible as compared to upper storeys. Under earthquake excitations, inter storey drift and demand of lateral shear force are maximum at the ground storey and from performance during past earthquakes it has been observed that this type of structural con guration are more vulnerable to earthquake. Experiences during past earthquakes shows that buildings on hill slopes are more vulnerable to earthquake excitations than the buildings on the plane ground. Step-back and step-back{setback are the most common con guration of buildings, used on the hill slopes. Major issues faced by the buildings on the hill slopes are, instability of the slope, lateral earth pressure, di erential settling of foundation, etc. In presence of lateral loading, buildings on hill slope exhibit torsional coupling and result in concentration of shear force, on the sti side of the building. To avoid these problems, some studies has been carried out with increased capacity of the lateral load resisting member or with shear wall to the exible side of the buildings. But increasing capacity of the lateral load resisting member or adding shear walls has an adverse e ect on stability of slope and on di erential settlement of foundation. In this study, a G+5 storey buildings with open ground storey on plane ground and another G+5 storey building with open bottom storey on hill slope with slope angle 30 is taken into consideration. The idea is to keep enough open spaces without compromising on the functional requirements of the building. So, three con guration of open space friction slider damper for buildings on plane ground and another two con guration of friction slider damper for buildings hill slope has been considered for this study. Analyses are carried out with OpenSees FE platform and results are compared, to the respective models without friction slider damper. From results, it has been observed that generally structural response of the buildings with friction slider damper is less than the building without friction slider damper and e ciency of friction slider damper increases with increase in relative displacement between the friction surfaces of slider.