Integrating Double-Skin Facades and Mass Dampers for Structural Safety and Energy Efficiency

A new integrated control system was recently proposed to combine double-skin facades and mass dampers in buildings to improve both building safety and energy efficiency. Double-skin facade systems protect and insulate buildings with two heavy glass layers between which air is allowed to flow for ventilation. By enabling movements in the outer facade skin, the authors proposed to (1) use them as mass dampers to reduce structural vibration and damage during earthquakes and wind storms and (2) adjust the gap size between the outer and inner skins to control the ventilation rate and improve energy efficiency. The synergy of the proposed system can lead to buildings that are structurally safe, energy efficient, and ultimately sustainable. In this paper, two structural control strategies-passive and active-are considered. The facade damper system was formulated first, and stochastic and historical earthquake responses were simulated. Then, the damper parameters (stiffness and damping coefficients) for passive control were optimized using a parametric study to minimize structural responses under earthquake excitations. Five configurations with 1, 2, 4, 5, or 10 dampers were optimized and analyzed; the optimized passive configurations can significantly reduce vibrations. Active control strategies were then applied to these five damper configurations using a linear-quadratic regulator. Different control weights were evaluated to balance performance in reducing story-to-story drifts and accelerations, and the resulting active systems outperformed their passive counterparts. (C) 2016 American Society of Civil Engineers.