Adaptive control strategy for enhancing multi-hazard resilience of MR damper-equipped inelastic structures with re-entrant corners

Abstract

Intelligent control systems, such as semi-active dampers utilizing magneto-rheological (MR) fluid, have proven effective in dissipating seismic energy. However, their performance under explosion loading remains relatively unexplored. This study addresses this gap by investigating the behavior of MR dampers in preventing progressive collapse in asymmetric, inelastic reinforced concrete (RC) frame structures subjected to explosion loading. To this end, three MR-damper-equipped concrete moment frame structures (with 4, 8, and 12 stories) featuring re-entrant corners are modeled using nonlinear fiber elements in OPENSEES. A robustness analysis of a supervisory nonlinear adaptive semi-active control strategy, developed in prior studies, is conducted to enhance the resilience of these structures under pulse-like seismic motions, blast loading, and progressive collapse, while also considering potential inelastic responses due to multiple natural hazards. The results show that MR dampers, originally designed for seismic loads, are also effective in mitigating structural responses to explosions, achieving up to an 80 % reduction in inter-story drifts. Furthermore, the new control strategy improves building resilience to progressive collapse under explosion scenarios, enhancing structural integrity by 10–80 % across various column removal scenarios. The findings highlight that the effectiveness of MR dampers in counteracting sudden column removal improves with the height of the building.