A large number R.C.C. multistoried buildings are heavily damaged and some of them are collapse, due to vertical irregularity of structure in earthquake zone. Uncertainties involved and behavior studies are vital for all civil engineering structures. The presence of vertical irregular frame subject to devastating earthquake is matter of concern. Points of sudden change of stiffness, mass and strength in building are known as weak points. For design safe irregular building it is necessary to study the effect of irregularity on the response of building for lateral loads. The present thesis research attempts to investigate the proportional distribution of lateral forces evolved through seismic action in each storey level due to changes in mass of frame on vertically irregular structures. In this paper effect of mass irregularity of G+10 storey vertical geometric irregular building using finite element method based software ETABS is studied. Two methods of analysis namely linear static and linear dynamic analysis are used to evaluate response of Structure in the form of Storey shear, Storey displacement and storey drift. Response are plotted and compared and final conclusions have been made.
