Perilaku Struktur Bangunan Dengan Ketidakberaturan Vertikal Tingkat Lunak Berlebihan Dan Massa Terhadap Beban Gempa

. Configuration Variation of building structures may result in systems irregularities of the structures. Two types irregularities which are often encountered are the excessive lateral soft stories and masses. Structural responses due to the excessive lateral soft storey and mass irregularities of 20-storey reinforced concrete structures are compared with the response of the similar building but structurally regular subjected to large earthquake motion. The dual systems of RC structures are designed comply with The Indonesian Standard SNI-1726-2012 and SNI-2847-2002 for earthquake resistant design. The major earthquake considered is the El-Centro 1940 N-S which is scaled match the design earthquake of Jakarta site class E. The excessive soft storey lateral irregularity is designed using variable of one story having 60% less stiffness compared with the above stories while the variable of mass irregularity is assigned to one particular floor having 150% larger mass compared to any other stories. The structural responses are analyzed using Performance Based Design under Non-Linear Analysis with Perform3D software. It was found that the building with the vertical soft stories combined with mass irregularities located in the first story showed the poorest performance