Effects of the accidental eccentricity on regular and irregular buildings

Abstract

The response of any building during seismic loading conditions might be affected by several factors, the horizontal torsion effect which generated by the eccentricity between centre of mass and centre of rigidity has conspicuous impact on the total response of building however, in many of the modern codes this influence is introduced by adopting the accidental eccentricity (AE) concept. In this paper analytical evaluation was done to assess the impact of the accidental torsion on high-rise structures with asymmetrical and symmetrical plan configurations in order to estimate the horizontal torsion effects for both regular and irregular structures during a high-intensity earthquake. The linear-static method, linear-dynamic (RS) method and time history method are the followed procedures for analysing the models, whilst the provisions of the considered codes are the Indian standard provisions and uniform building code 97 provisions, three different conditions were applied the first applying the seismic later load without accidental-eccentricity (AE), the second case is assuming %5 of (AE) which is worldwide presupposed value in many of seismic codes, where the third condition is adapting an accidental-eccentricity (AE) calculated according to the selected seismic codes. ETABS 2016 Software was utilized for analysing all models.