Evaluation of floor response spectra to Assessment Seismic Demands of Nonstructural Components in Steel Moment Frame

Always share of damages of non-structural components is a significant share of the total cost of earthquake damages. A simple method for analyzing the response of non-structural members, is use the floor response spectrum. In this method, first behavior of primary structure at the non-structural member nodes regardless of their interaction is determined. Then the response of non-structural members used as input to the analysis result. In this study, six two-dimensional steel moment frame, three, six and twelve-story is modeled. In order to investigate the effect of  changing period in the force exerted on non-structural components there are two models, one with more (flexibility) and one with a smaller period (rigid). 7 record ground motion recorded on soil types that respect to the code design of the buildings against earthquakes (Iran standard no.2800) scale, has been used for time history analysis. The results obtained were compared with suggested values by conventional codes. From this study it was concluded that the focus of energy absorbing of structures is related to the first e and second mode and the height increases, the tendency to absorb energy will be increased. Distribution of amplification factor of seismic response at high (ratio of peak floor acceleration to the peak ground acceleration) to studied frames showed that the amplification factor proposed by Euro code 8 are closer than to be obtained when the period of non-structural component is closer to of the first period of the structure, the phenomenon of resonance occurs and when the structural period increases (tall buildings) effect of higher modes is increased, this means that the resonance mode in the second and third periods will occur.