Large-scale experimental evaluation and numerical simulation of a system of nonlinear energy sinks for seismic mitigation

• Published in: Engineering structures Vol. 77; pp. 34 - 48
• Main Authors: Luo, Jie, Wierschem, Nicholas E., Hubbard, Sean A., Fahnestock, Larry A., Dane Quinn, D., Michael McFarland, D., Spencer, Billie F., Vakakis, Alexander F., Bergman, Lawrence A.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 15.10.2014; Elsevier
• Subjects: Applied sciences; Buildings; Buildings. Public works; Dynamic vibration absorber; Essential nonlinearity; Exact sciences and technology; Geotechnics; High rise building; Passive control; Seismic excitation; Shake table testing; Stresses. Safety; Structural analysis. Stresses; Structure-soil interaction; Types of buildings; Dynamic vibration absorber; Seismic excitation; Passive control; Essential nonlinearity; Shake table testing; Earthquake engineering; Absorber; Nonlinear analysis; Dynamical system; Passive system; Experimental study; Modeling; Shaking table; Seismic analysis; Energy dissipation; Nonlinearity; Numerical simulation; Vibration control; Large scale; High rise building; Comparative study
• ISSN: 0141-0296; 1873-7323
• DOI: 10.1016/j.engstruct.2014.07.020

•Shake table tests were performed on a large-scale model building equipped with NES devices.•Experimental results demonstrate that effective mitigation of seismic responses was achieved.•A numerical model was developed and two suites of ground motions were selected.•Numerical simulation results demonstrate effectiveness and robustness of NES devices. As a novel dynamic vibration absorber, the nonlinear energy sink has been studied for mitigating structural and mechanical vibration through the last decade. This paper presents a series of large-scale experimental evaluations and numerical simulations on a system of nonlinear energy sink (NES) devices for mitigating seismic structural responses. Two distinct types of NES devices were installed in the top two floors of a large-scale model building structure. In the device system, four Type I NESs employing smooth essentially nonlinear restoring forces were used in conjunction with two single-sided vibro-impact (SSVI) NESs employing non-smooth impact nonlinearities. These NES devices utilize the existing structural mass and space of the model building to realize an integrated design of building structure with non-parasitic control devices. Scaled historic earthquake ground motions were implemented by a large-scale shake table as the base excitation input into the system. Direct comparisons between mitigated and unmitigated structural responses, including story displacement, column strain and base shear force, demonstrate that rapid mitigation of structural responses was achieved by the system of devices. Reductions of both peak and average values of structural responses were clearly observed. The synergistic effects obtained by simultaneously using two types of NES devices were demonstrated. To computationally investigate the mitigation performance of the devices subjected to a wide variety of ground motions, a numerical model was developed for the structure-NES system and two suites of earthquake ground motions representing distinct earthquake intensities were employed. Simulation results demonstrate that mitigation of structural responses caused by diverse earthquake ground motions can be achieved by a system of NES devices.