TY - GEN
T1 - Dynamic frequency de-tuning using controllable beamcolumn semi-rigid connections
AU - Widjaja, J.
AU - Samali, B.
AU - Li, J.
AU - Reizes, J.
PY - 2005
Y1 - 2005
N2 - The concept of frequency de-tuning and damping enhancement to avoid resonant frequencies and to suppress the vibration response of structures, respectively, has been known for passive vibration control systems since mid 1950's. Ideally the concept shifts the structural frequency away from resonant frequency and significantly reduces the structural response in the 'narrow-band' dampingcontrolled region. However in reality, the passive vibration control performance depends heavily on the dynamic characteristics of energy dissipation systems that are fixed and only applicable for a particular frequency band. Conversely, the Direct Current (DC) controllable beam-column semirigid connections using Magneto-rheological (MR) rotational fluid dampers, can act as real time adjustable passive control devices for any required frequency band. The supplied DC current level can adjust the device torque and rotational velocity characteristics that affect the structural frequency. This paper presents a preliminary parametric study on vibration control performance of a single and a two storey prototype plane frame model due to combination of frequency de-tuning and its associated damping enhancement by selecting end beam connections as either hinged or fixed. The controllable semi-rigid connection characteristics are represented in terms of normalised frequency. And the control performance indicated by Amplitude Frequency Characteristics (AFC) of the models is studied numerically and presented graphically. The study yields an insight into the controllable connections prior to any experiments.
AB - The concept of frequency de-tuning and damping enhancement to avoid resonant frequencies and to suppress the vibration response of structures, respectively, has been known for passive vibration control systems since mid 1950's. Ideally the concept shifts the structural frequency away from resonant frequency and significantly reduces the structural response in the 'narrow-band' dampingcontrolled region. However in reality, the passive vibration control performance depends heavily on the dynamic characteristics of energy dissipation systems that are fixed and only applicable for a particular frequency band. Conversely, the Direct Current (DC) controllable beam-column semirigid connections using Magneto-rheological (MR) rotational fluid dampers, can act as real time adjustable passive control devices for any required frequency band. The supplied DC current level can adjust the device torque and rotational velocity characteristics that affect the structural frequency. This paper presents a preliminary parametric study on vibration control performance of a single and a two storey prototype plane frame model due to combination of frequency de-tuning and its associated damping enhancement by selecting end beam connections as either hinged or fixed. The controllable semi-rigid connection characteristics are represented in terms of normalised frequency. And the control performance indicated by Amplitude Frequency Characteristics (AFC) of the models is studied numerically and presented graphically. The study yields an insight into the controllable connections prior to any experiments.
UR - http://www.scopus.com/inward/record.url?scp=34250888111&partnerID=8YFLogxK
M3 - Conference Paper
AN - SCOPUS:34250888111
SN - 9781627481274
T3 - 4th Australasian Congress on Applied Mechanics, ACAM 2005
SP - 807
EP - 813
BT - 4th Australasian Congress on Applied Mechanics, ACAM 2005
T2 - 4th Australasian Congress on Applied Mechanics, ACAM 2005
Y2 - 16 February 2005 through 18 February 2005
ER -