الفهرس 
Chapter 1 1. INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Structural fuses are sacrificial structural elements that can be added to Reinforced Concrete (RC) systems to reduce the damage under seismic loads. Structural fuses can be constructed from a variety of ductile materials and shapes. Several structural systems were studied while using structural fuses to investigate their behavior enhancement under seismic loads. Coupled shear walls system is chosen in this research to be investigated while installing steel fuse coupling beams with specific recommendations instead of conventional concrete beams. A non-linear finite element analysis is conducted using ABAQUS FE program to verify the modeling of steel fuse beams under shear loading, and Seismostruct FE program to verify modeling of global reinforced concrete system under lateral loads based on available experimental results.
A parametric study is then conducted using the verified micro and macro modelling techniques through two phases. Phase one aims to determine the optimum dimensions for steel fuse coupling beams to enhance their performance in terms of shear-deformation capacity, and energy absorption ensuring early shear yielding instead of flexural yielding under shear loading. The second phase aims to study the effect of installing steel beams with the design guidelines deduced from phase one instead of conventional RC beams with the same shear capacity and predict the effect of this procedure on the global behavior of the main system. Additionally, web modification of built up steel section is studied to increase the shear ductility of steel fuses, and hence protect the global system from damages at larger top displacements. Moreover, the location pattern of steel coupling beams along the height of the shear walls is investigated in order to deduce the most effective or non-use locations. Nevertheless, the effect of vertical static load acting on top of the shear walls is investigated against global behavior of studied system.
In conclusion, RC coupled wall systems with steel coupling beams showed better performance in terms of ductility, energy dissipation, and damages level while maintaining similar shear capacity compared to the ordinary systems coupled with RC beams. Moreover, a specific steel fuse pattern and vertical load ratio is recommended to ensure better performance of the global system. The modified web design for steel built up section showed enhancement in global system behavior in terms of energy dissipation and top displacement capacity but resulted in a little decrease in base shear capacity. A specific factor range that depends on cross section dimensions and beam length is identified for steel beams to ensure better shear behavior.