Introducing Building Casketing as a new Technique for Seismic Retrofit of Existing Buildings with L Shaped Plan

In order to retrofitting by the peripheral frames method for structures with L shaped plan, we have 6 models to examine the effect of changes in dimensions plan and elevation of the building be considered. Models are with moment resisting frame systems that designed with the old seismic and concrete regulations. Nonlinear static and dynamic and endurance time method analysis on the models was done. According to the results, the models have not life safety level and need to retrofitting. Have upgraded seismic performance level of the models by adding peripheral frames to the structure.The retrofitting models evaluated by the new regulations and according to the results, the retrofitting models reach to the life safety performance level and target displacement have decresed