Echtzeitgeregelte Massendämpfer für Wolgograd‐Brücke

Abstract

Im Mai 2010 traten auf der Wolgograd‐Brücke windinduzierte Biegeschwingungen mit geschätzten Amplituden bis 40 cm auf. Seit November 2011 wird die Wolgograd‐Brücke durch adaptive Massendämpfer bedämpft, deren Frequenz und Dämpfung über geregelte MR‐Dämpfer in Echtzeit an die aktuelle Schwingfrequenz der Brücke angepasst sind. Im schlechtesten Fall bedämpft dieses Konzept die Brücke gleich stark wie passive Massendämpfer und in allen übrigen Fällen stärker. Diese Verbesserung ist mit ungefähr nur halb so viel Massendämpfermasse im Vergleich zu passiven Massendämpfern erreicht, was der Bauweise der Brücke entgegenkommt.Real‐time controlled tuned mass dampers for Wolgograd BridgeIn May 2010, the Wolgograd Bridge underwent wind‐induced bending vibrations with estimated amplitudes of up to 40 cm. Since November 2011, the Wolgograd Bridge is mitigated by adaptive tuned mass dampers whose frequency and damping are adjusted to the actual frequency of vibration in real‐time by controlled MR dampers. This concept mitigates the bridge in the worst case similarly to and in all other cases better than passive tuned mass dampers. This improvement is achieved by approximately half the mass damper mass compared to passive tuned mass dampers which is a desirable feature for the bridge construction type.

Schrägseilbedämpfung mit echtzeitgeregelten MR‐Dämpfern

“…Die Sollkraft für den MRDämpfer ist (6) wobei der Sollwert des viskosen Koeffizienten c soll in Echtzeit an die Frequenz der aktuellen Seilschwingung angepasst wird, wodurch auch tageszeitliche Schwankungen der Seileigenfrequenzen kompensiert werden. fr wird aus den lokalen Extrema von x a in Echtzeit bestimmt [13,14]. Die aktuelle Schwinggeschwindigkeit x · a wird mittels numerischer Differentiation von x a berechnet und mittels Tiefpassfilterung geglättet.…”

MR Damper Controlled Vibration Absorber for Enhanced Mitigation of Harmonic Vibrations

“…Wind-induced excitation forces may lead to structural vibrations with extremely large amplitudes as observed on the Volgograd Bridge, Russia, in 2010 or on the Taipei 101, Taiwan, during typhoons in 2008, 2013 and 2015 [1][2][3][4]. The oscillation amplitudes are maximized if all excitation energy is transferred into one vibration mode of the structure, which is the case when the excitation mechanism such as vortex shedding generates harmonic excitation forces [5].…”

“…In order to compensate for time-varying modal properties of the primary structure due to, e.g., environmental impacts or to improve the mitigation efficiency in the vicinity of the targeted structural eigenfrequency adaptive TMDs have been developed. These devices rely on actively controlled spring systems, Piezo stacks, shape memory alloys, controllable dampers such as magnetorheological (MR) dampers and other types of actuators [2,3,[9][10][11][12][13][14][15][16][17][18][19][20][21]. According to the literature the resulting vibration mitigation is improved by up to 50% compared to the passive TMD [17,18].…”

“…Finally, a summary with concluding remarks is given. It is understood that parts of this entire R & D work that started in 2010 with the project of the Volgograd Bridge [2,3,18] and is still continuing can be found in the existing literature. The aim of this paper is therefore to give a comprehensive description of this R & D work to show the continuous further developments and-as a final outcome of this longtime work-describe the latest improvement that the MR-SVA can be operated with reduced damper mass almost without any losses in vibration reduction efficiency.…”

“…The experimental validation of the prototype MR-SVA is performed with a suboptimally tuned f passive as the passive mass spring packet of the MR-SVA was originally designed to assess the semi-active TMD concept of the Volgograd Bridge, Russia [2,3,18,21], which required to design f passive according to the design of TMDs for minimum structural displacement [6], i.e.,…”