THE EFFECTS OF MASS ECCENTRICITY SCENARIO ON THE SEISMIC TORSIONAL BEHAVIOR OF RC/MR BUILDINGS

In this study the effect of different mass eccentricity scenarios on the dynamic torsional behavior of an 8-story RC moment resistant building has been investigated. Firstly, to determine the range of the mass moment inertia (MMI) variation due to different mass distribution scenarios, three different scenarios which produce eccentricity were considered. These scenarios were applied to the plan of prototype structure and expressions were established to correlate MMI and mass eccentricity in each scenario. Result shows for slight eccentricities the variation of the MMI is negligible but as eccentricity is increased the range of the variation is extended. At the second part of this study, 8-Story RC moment resistant building was designed according to the Iranian seismic code (Standard No. 2800, 3rd Edition). Sensitivity analyses based on finite element method and inelastic time history analysis have been carried out for determining the effects of MMI on the torsional response of the structure.The effects of the variation of MMI on the torsional response of the structure at 2 level of mass eccentricity including slight and severe is investigated and described in detail.