Energy based assessment of the reinforced concrete walls with two outriggers

Abstract

In this paper, different kind of energy dissipation in reinforced concrete (RC) core-wall systems with two buckling-restrained braced outriggers subjected to forward directivity near-fault and ordinary far-fault earthquakes has been compared. The level of the first outrigger is fixed at the top and the second outrigger is placed at different levels. In the nonlinear model, two approaches for the RC core-wall were considered: extended plastic hinge (EPH) approach and 4 plastic hinges approach (4PH). In 4PH approach, only 4 plastic hinges are allowed in the RC core-wall, one at the base, one another adjacent beneath the top outrigger, and two others at the levels adjacent second outrigger. For EPH approach, the plasticity can extend anywhere in the core-wall. Principally for the EPH approach, at the base of core-wall and adjacent to top outrigger as well as above and below of second outrigger level, more inelastic energy demands are occurred due to large moment demand resulting from seismic load. On average for both EPH and 4PH approaches, the inelastic energy at the base from far-fault records is almost 1.5 times the corresponding value from NF records.