SEISMIC RESPONSE OF HYBRID FRAME STRUCTURES FOR VARIOUS SEISMIC ZONES
by Sameer Ahmed
Abstract
After the incident and lesson learnt from Bhuj earthquake it shows the importance of civil structure engineering. During structure analysis the response spectrum method is used to get the seismic response of the structure. The analysis approach is done by STAAD pro. for G+12 storied building having seismic response of different hybrid frame structures are considered for seismic Zones II to Zone V by using response spectrum method to find out the nodal displacements and also determine the cost percentage of the structure. The comparative cases of hybrid structure are classified as, Case 1: RC Frame Structure, Case 2: RC Frame Structure with Shear wall Systems, Case 3: RC Frame Structure with Braces, Case 4: RC Frame Structure with Shear wall Systems and with X- Concrete and X- Steel bracing, Case 5: RC Frame Structure with Shear wall Systems and with outer frame of Steel Bracing, having individual case studies for seismic Zone II to Zone V. The comparative results of RC Frame Structure of Case 5: RC Frame Structure with Shear wall at centre and corner and with outer frame of I-section bracing is determined as best hybrid structure which resist the lateral forces with minimum node displacement i.e. 52.628 mm at Zone V. In individual case study the best type of hybrid technique is also analyze from seismic zone to resist the lateral forces, the shear wall at centre and corner of the structure with outer frame of I-section bracing with the node displacement of Zone II = 14.618 mm, Zone III = 23.390 mm, Zone IV = 35.085mm, Zone V= 52.628 mm and displacement decrease in percentage with respect to reinforced concrete frame for seismic Zone II to Zone V are 91.50%, 91.50%, 91.72% and 91.56%. From cost effectiveness Reinforced Concrete shear wall at center and corner of the structure with outer frame of cross I section bracing is best hybrid structure. Therefore hybrid structure and its technique are the future necessity to get the high performance results in seismic vulnerability. Keywords: Earthquake, Seismic response, Hybrid structure, Hybrid techniques, Shear wall, Bracing, Seismic Zones, Nodal displacement, Reinforced concrete frame
