Friction damper optimization based on parallel sensitivity analysis for self-centering concrete walls with gravity columns

In recent years, self-centering concrete walls have been utilized as modern structures. The mechanism of these structures is such that the focus of energy dissipation is on the dampers, and the role of the concrete wall and tendons is to create stiffness and provide the self-centering capacity in the system resulted in the reduction of residual deformation in the system. The jointed self-centering concrete walls are a type of self-centering wall system where dampers are placed between two concrete wall panels. The most important point that should be considered in these structures is the optimal use of dampers in them. In the present research, a new system has been introduced, which is a combination of self-centering concrete walls with gravity columns. In such a way that the friction dampers were placed in the middle and side positions of the concrete wall. This research aimed to investigate the optimal numerical value for the "slip load of friction dampers" in the middle and side positions of the Self-centering concrete wall based on the "amount of prestressing force" in the friction screws of the dampers. In the current study, the resistance of damper materials, their shape and dimensional size are not considered as variable parameters and they are considered without influence in determining the optimal damping. In total, the optimal sliding load based on the prestressing force in the friction bolts has been simultaneously determined by two-way sensitivity analysis by OpenSEES software. Based on the results, applying the method of determining the percentage of the minimum response coefficient (R) based on parallel (two-way) sensitivity analysis can be recognized as a very efficient method for determining the most optimal friction damper in Self-centering jointed concrete wall systems. Furthermore, the prestressed and optimal force for the dampers indicated that the dampers located between the two walls (set of middle dampers) exhibit a specific optimal value and other dampers (set of side dampers) also present a different optimal value.