Performance of Shape Memory Alloy Lead Rubber Bearing (SMA-LRB) Isolated Building Under Blast-Induced Ground Motion Considering Parametric Uncertainty

Abstract

Blast-induced ground motions (BIGM) can cause significant damage to the structure, leading to loss of life and economy. Previous studies proposed the use of base isolation system to prevent such adverse effects of blast loading on the structures. This study explores the effect of parametric uncertainty on the performance of shape memory alloy-assisted lead rubber bearing (SMA-LRB) isolator for the vibration control of building, under the BIGM. Nonlinear time-history analyses are performed to estimation responses, and compared them with the LRB isolated building. The building is modeled as a linear system, and nonlinear force–displacement behavior of LRB and SMA has been modeled via Bouc–Wen model and thermo-mechanical material model. To identify the critical design parameters and study the effect of parameter uncertainty, sensitivity analysis and Monte Carlo (MC) simulation are performed. Study results reveal that, compared to LRB, SMA-LRB reduces the peak floor acceleration by 20% with an added benefit of 35% and 67% reduction in peak and residual isolator displacement. Parametric uncertainty causes noticeable increase in mean responses of LRB isolated system than deterministic case, which get diminishes for SMA-LRB isolation system. This increase in the mean value of peak floor acceleration, peak, and residual isolator displacement are 64%, 68%, and 60% less for SMA-LRB than LRB isolated building. Further, compare to the LRB, SMA-LRB reduces standard deviation by 77% for the peak floor acceleration and peak isolator displacement, and 85% for the isolator residual displacement. Thus, conjunction of SMA with the LRB isolator enhances the performance and provides robust control effect under parameter uncertainty.