Numerical study of damage index of 2d steel building with eccentrically braced frame using OPENSEES

Measuring degree of damage of structure under an earthquake has been researched by numerous researchers since it is difficult to ensure whether the designed building structure could withstand. In earlier research, structural damage detection method used natural frequency to indicate damage. However, this method is not spatially specific, nor are they sensitive to damage. Thus, damage index is introduced as a tool to measure the damage in specific scale of zero to one. Among different types of damage index, Park-Ang damage index is used. Model of building structure that will be analysed is steel building with Eccentrically braced frame system. EBF system has extraordinary characteristics which has high ductility of dissipating energy and also sufficient stiffness to prevent from buckling. 2D model of EBF building with variation of number of story (one, three and five story) is identified regarding to behaviour, damage index and natural frequency. The behaviour of EBF building is identified by observing the monotonic and semi-cyclic pushover analysis. Damage index of EBF building structure is identified using OpenSees program. Furthermore, natural frequency that also measure degree of damage is identified using SAP2000. By determining damage index and natural frequency, the correlation between two can be observed.