9729679 Saadatmanesh This project will conduct a preliminary analytical and experimental study to investigate the feasibility of strengthening buildings by plastic materials. The analytical study will focus on the optimization of the relative ratio of the carbon and glass fibers for the best absorption and dissipation of the energy due to a blast loading. The theory will be developed in general format that could be applicable for the design of this strengthening system for a typical building. The experimental part of the study will focus on the evaluation of this concept under simulated blast loading delivered by means of a high impact load. Concrete as well as brick speciments will be constructed and retrofitted with the hybrid composite sheet and then tested under impact loading. Control, unretrofitted specimens will also be tested. The test results will verify the effectiveness of this strengthening system. ***