Free Vibration of a Taut Cable with Two Discrete Inertial Mass Dampers

Abstract

Recently, inertial mass dampers (IMDs) have shown superior control performance over traditional viscous dampers (VDs) in vibration control of stay cables. However, a single IMD may be incapable of providing sufficient supplemental modal damping to a super-long cable, especially for the multimode cable vibration mitigation. Inspired by the potential advantages of attaching two discrete VDs at different locations of the cable, arranging two external discrete IMDs, either at the opposite ends or the same end of the cable is proposed to further improve vibration mitigation performance of the cable in this study. Complex modal analysis based on the taut-string model was employed and extended to allow for the existence of two external discrete IMDs, resulting in a transcendental equation for complex wavenumbers. Both asymptotic and numerical solutions for the case of two opposite IMDs or the case of two IMDs at the same end of the cable were obtained. Subsequently, the applicability of asymptotic solutions was then evaluated. Finally, parametric studies were performed to investigate the effects of damper positions and damper properties on the control performance of a cable with two discrete IMDs. Results showed that two opposite IMDs can generally provide superior control performance to the cable over a single IMD or two IMDs at the same end. It was also observed that attaching two IMDs at the same end of the cable had the potential to achieve significant damping improvement when the inertial mass of the IMDs is appropriate, which seems to be more promising than two opposite IMDs for practical application.

Editorial for “Recent Advances in the Design of Structures with Passive Energy Dissipation Systems”

“…Some papers in the Special Issue concern the development of inerter-based vibration control strategies, and their deployment in civil engineering structures and infrastructures. The inerter modifies the inertial properties of the structures while adding negligible physical mass, and it may be a cost-effective solution for both seismic [2,4] and wind [1,3] vibration control. Some other papers concern the development of efficient design methods that exploit state-of-the-art algorithms and solvers for the optimization of the devices [11,13].…”

“…In paper [1], Wang et al present free vibration analysis of a taut-cable with two inertial mass dampers (IMDs) either symmetrically placed along the cable, or installed at the same end of the cable. The results in terms of the supplemental modal damping ratio provided by the IMDs for the two installation configurations and for different values of the damping coefficient are obtained by complex modal analysis, and are critically discussed.…”

Free vibration of a taut cable with a parallel-connected viscous mass damper and a grounded cross-tie

“…Substituting equation (4) into equation (1), U ( x ) in each span needs to satisfy a homogeneous equation 45,46 where βn=ωnm/T refers to the wave number.…”

Ultrathin structures derived from interfacially modified polymeric nanocomposites to curb electromagnetic pollution

“…For a film thickness of 100 μm, the SE T was reported to be -77 dB in X-band. Wang et al 24 fabricated nitrogen-doped graphene multilayer films by thermal annealing of the stacked graphene oxide/copper phthalocyanine (GO/CuPc) multilayer films. The maximum SE T value of -55.2 dB was obtained for a shield thickness of 0.47 mm in the X-band.…”