Seismic force modification factors for partitions in low-rise reinforced concrete buildings

Present codes of practice do not consider the effect of the arrangement of partitions in the plan of structure on the seismic demands of these non-structural components. In this paper, a modification factor has been proposed to modify provisions for those seismic demands. Seventy-two regular low-rise reinforced concrete moment frames, supporting some partitions, are exposed to seven appropriate ground motions. The nonlinear seismic response history analysis considering out-of-plane behavior of partitions was conducted using the OpenSees platform. The average values of peak responses from those earthquakes were obtained. The forces generated using the analytical method, some of which were verified by the existing study results, were compared with the values from the code, and a factor denoted by seismic force modification factor, , was proposed. A parametric study was carried out to study the effect of dominant parameters such as the arrangement of partitions, partition to structure height ratio, and length-to-height ratio of partitions on values. For a majority of models, values are larger for partitions that are located farther away from the center of the floor. Moreover, the modification factor could be as large as 1.85 for the partitions located on the middle floors.