Comparing Static Linear And Nonlinear Analyses Of Safe Rooms In A Poor Performance Masonry Building

Abstract

The idea of safe rooms has been developed for decreasing the earthquake casualties in masonry buildings. The information obtained from previous ground motions occuring in seismic zones expresses the lack of enough safety of these buildings against earthquakes. For this reason, an attempt has been made to create some safe areas inside the existing masonry buildings, which are called safe rooms. The practical method for making these safe areas is to install some prefabricated steel frames in some parts of the existing structure. These frames do not carry any service loads before an earthquake. However, if a devastating earthquake happens and the load bearing walls of the building are destroyed, some parts of the floors, which are in the safe areas, will fall on the roof of the installed frames and the occupants who have sheltered there will survive. This paper presents the performance of these frames located in a destroying three storey masonry building with favorable conclusions. In fact, the experimental pushover diagram of the safe room located at the ground-floor level of this building is compared with the analytical results and it is concluded that pushover analysis is a good method for seismic performance evaluation of safe rooms. Also this experimental diagram shows that the strength and displacement capacity of the steel frame are adequate to accommodate the distortions generated by seismic loads and aftershocks properly.