IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) e-ISSN: 2278-1684,p-ISSN: 2320-334X, Volume 12, Issue 5 Ver. IV (Sep. - Oct. 2015), PP 123-131 www.iosrjournals.org DOI: 10.9790/1684-1254123131 www.iosrjournals.org 123 | Page Seismic Performance Evaluation Of Reinforced Concrete Frames Hasan Hastemoglu Abstract: Ten storied -3bays reinforced concrete bare frame designed for gravity loads as per IS 456: 2000 (rev) and IS 13920: 1993 for ductility is subjected to seismic loads. Seismic loads considered is earthquake loads determined from IS 1893-2002 (part 1) response spectra for 5% damping (for hard soil). Structural elements are modeled as two node element (three degrees of freedom at each end). Plastic hinges are used to represent the failure mode in the beams and columns when member yields. Pushover analysis is performed using SAP 2000 V 14.0 commercial software in reference to various performance levels suggested in first, second and next generation performance based design procedures (ATC 40, FEMA 356, FEMA 440). Base shear versus top displacement curve of structure, known as pushover curve is obtained for force-displacement (brittle) and Deformation-controlled (ductile) actions of plastic hinge. Lateral deformation at performance point proves the building capability to sustain certain level of seismic loads. The failure mechanism indicates structural performance levels in accordance first, second and next generation PBSD procedures. The study aims towards understanding the first, second and next generation PBSD evaluation procedures. Keywords: PBSD evaluation procedures, Building frames, Plastic hinges, Pushover analysis, Seismic Performance I. Introduction Present seismic design codes, describes forced–based design procedures for lateral load resistance structures [1]. In static case loads on structure are low resulting in elastic behavior. During strong seismic event, these structures are subjected to loads beyond its elastic limits [2]. Though the present code can provide reliable indication of expected performance for life safety (strength and ductility) and damage control (serviceability drift limits) but are incapable to describe the expected performance, under large forces [3]. Performance based seismic design has emerged as best alternative towards present seismic code design procedure which is capable to describe the inelastic behavior of structure. PBSD, where inelastic structural analysis in combination to defined seismic hazard level is used to obtained expected performance of structure [1]. Second generation procedure recommends four analysis procedures to estimate seismic demands as presented in table 1[4]. Next generation procedure presents improvements in first and second generation procedures [8]. Amongst this Nonlinear Dynamic Procedure (Time history, NLTH) is capable to calculate seismic responses under strong earthquakes, but results in large amount of data and time consuming process hence not considered practical. Practicing field engineers prefers nonlinear static procedure (Pushover, NLSP) procedure due to easy and compatible compared to results obtained through NLTH [5-9]. First, second and next generation procedure provides various building performance levels based on contribution of structural and non structural performance levels in reference to transient and permanent drift as presented in table 2 [10]. The various structural performance levels and damage for vertical elements described by various PBSD procedures are presented in table 3 [7] and used for modeling of example building frame in present study. Table 1: Various analysis procedures to estimate seismic demands suggested by second generation procedure [4] Type of Analysis Usual Name Dynamic Material Non- effects linearity Linear static Equivalent static No No Linear dynamic Response spectrum Yes No Nonlinear static Pushover No Yes Nonlinear dynamic Time history Yes Yes Table 2: Building Performance Levels [10] FEMA 273/356 SEAOC vision 2000 ATC 58 Rating Performance Rating Performance Anticipated Color code Levels Expectation damage S-1 Immediate 10 Fully operational Negligible Green occupancy Damage control 9 S-2 8 Operational Light 7 S-3 Life safety 6 Life safe Moderate Yellow