The energy factor β and energy dissipation by hysteresis in the behavior of hybrid concrete walls under reversible cyclical lateral loads

Resumen

The energy dissipation of hybrid walls is calculated in the area of the hysteretic cycles produced in the movement under lateral loads, this magnitude is taken as an index of the damage in the structural system. In addition, ACI ITG 5.1 defines the energy factor β as a dimensionless measure of dissipation related to areas in hysteretic cycles. In hybrid walls the lateral load behavior is related to the "energy dissipators", formed by corrugated steel bars, placed through the joint between the precast wall and the foundation, another element in these walls is the prestressing steel cable, this cable is attached to the top of the wall and crosses it to the bottom of the foundation, and gives recentering to the wall. The configuration of the hybrid walls takes advantage of the mechanical characteristics of these two elements, controlling high displacements and with focused damage. A numerical model was validated to represent the response of the hybrid walls, using the experimental results of the HW1 and HW3 walls tested by Smith et al. (2012) and Rahman et al. (2000), respectively. With the validated numerical model and the β factor defined, a comparison of the energy dissipated by similar hybrid and conventional walls was performed. The results show that hybrid walls dissipate about 30% of the amount of energy dissipated by a conventional wall of similar characteristics.