Improving energy dissipation capacity of FRP and hybrid shear walls

Developing lighter and more efficient structural members with sufficient seismic resistance will aid in the reduction of casualties and a decrease in structural damage. Application of steel bracing and reinforced concrete (RC) shear walls used for lateral load retaining systems (LLRS) are not always the most efficient and economical solution as they have longer construction times and are heavier compared to steel plate shear walls (SSW). Steel shear walls have shown its superiority over conventional concrete shear walls when implemented in high rise buildings, reducing the self-weight of the structure, as well as having high initial stiffness and energy adsorption. The latest developments in this area have proven that simultaneous application of steel and fibre reinforced polymer (FRP) materials for infill plates results in an increase of energy dissipation and ultimate load capacity. The beneficial influence of those factors for hybrid (FRP & Steel) shear walls will allow for developing of improved characteristics and wider applications in building practice. This research looks at the behaviour of the hybrid steel/FRP and FRP only connections and how variations in certain parameters will affect the load capacity and energy dissipation. This research also looks at the prospect of utilising these FRP materials in SSW infill plates by analysing the ultimate load capacity and energy dissipation of different specimens and evaluating the most efficient system. The FRP materials used are carbon and glass prepreg unidirectional fabric applied as layers on both sides of a thin steel plate. Displacement controlled loading sequence was developed following the ATC-24 loading protocol (Applied Technology Council, 1992). Ultimate load capacity, displacements and strain gauge readings were recorded for all tested specimens. Some of the main findings were that hybrid steel/CFRP infill plates suffered significant delamination, however presented some of the most ductile behaviour amongst the hybrid specimens. It was also concluded that variation in torque influences the mode of failure of SSW connections as well as the energy dissipation and load capacity. Connected experimental research and FEM prove the perspective of further application of indicated innovative variations of SSWs.