케이블 진동 감쇠를 위한 반능동 제어 장치 성능의 실험적 평가
DESCRIPTION
2004 년도 한국전산구조공학회 추계 학술발표회 목포해양대학교 2004 년 10 월 9 일. 케이블 진동 감쇠를 위한 반능동 제어 장치 성능의 실험적 평가. 장지은 , 한국과학기술원 건설 및 환경공학과 석사과정 정형조 , 세종대학교 토목환경공학과 조교수 정 운 , 현대건설기술개발원 주임연구원 이인원 , 한국과학기술원 건설 및 환경공학과 교수. Contents. Introduction Cable Damping Experimental Setup Experimental Results - PowerPoint PPT PresentationTRANSCRIPT
케이블 진동 감쇠를 위한
반능동 제어 장치 성능의 실험적 평가
케이블 진동 감쇠를 위한
반능동 제어 장치 성능의 실험적 평가
2004 년도 한국전산구조공학회 추계 학술발표회목포해양대학교 2004 년 10 월 9 일
장지은 , 한국과학기술원 건설 및 환경공학과 석사과정정형조 , 세종대학교 토목환경공학과 조교수정 운 , 현대건설기술개발원 주임연구원이인원 , 한국과학기술원 건설 및 환경공학과 교수
22Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
Introduction
Cable Damping Experimental Setup
Experimental Results
Conclusions
Contents
33Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
Introduction
Cable
• Cables are efficient structural elements that are used in cable-stayed bridges, suspension bridges and other cable structures.
• Steel cables are flexible and have low inherent damping, resulting in high susceptibility to vibration.
• Vibration can result in premature cable or connection
failure and/or breakdown of the cable corrosion protection
systems, reducing the life of the cable structure.
• Numerous passive and active cable damping studies have been performed and full-scale applications realized.
44Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
Semiactive damping system
- Johnson et al. (1999, 2000): verification of the efficacy of
a semiactive damper for a taut/sagged cable model
- Christenson (2001): experimental verification of the
performance of an MR damper in mitigating cable
responses by using a medium-scale cable
- Ni et al. (2002), Ko et al. (2002), Duan et al. (2002): field
comparative tests of cable vibration control using
MR dampers (the world’s first time implementation
of MR-based smart damping technology in civil
engineering structures)
55Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
Objectives
• To experimentally verify the performance of the MR
damper-based control systems for suppressing vibration of
real-scaled stay cables using various semiactive control
algorithms
66Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
Cable Damping Experimental Setup
Schematic of smart cable damping experiment
Where, )(tFs
: displacement at damper location
: shaker force
)(tFd : damper force
: evaluation displacement
shakershaker flat-sagcable
flat-sagcable
spectrumanalyzer
spectrumanalyzer
MR dampers
MR dampers
digital controller
digital controller
)(tFd
)(tFs
dw
dw
u
u
ew
ew: control signal
77Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
Cable
Real-scaled cable at HICT
parameters values
L 44.7 m
m 89.86 N/m
T 500 KN
1.34 m
13.4 m
8.37
2.53 Hz
dx
0005.0
0015.0
2
1
i
0
sx
88Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
Cable model
• Transverse motion of cable could be modeled by
the motion of a taut string because of small sag
(0.1% sag-to-span ratio with tension of 500 kN).
99Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
dx sx
),( txvx
where ),( txv
)(tFd dxx : transverse deflection of the cable
: transverse damper force at location
)(tFd )(tFs
)(tFs sxx
L
: transverse shaker force at location
: angle of inclination
1010Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
MR damper
• MR controllable friction damper
(RD-1097-01 from Lord Corporation)
• Maximum force level: 100 N
• Maximum voltage: 1.4 V
1111Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
MR damper installation
• Twin damper setup
• Location : 1.34m
from bottom support
• Measurement : Damper force,
displacement, and
acceleration
1212Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
Cable exciting system (Kim et al. 2002)
temtF sin)( force exciting Harmonic 2
mass exciting :
frequency exciting : where
m
(1)
1313Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
Controller
• The controller is constructed by the Matlab Real-Time
Workshop executed in real time using MS Visual C++.
• The measured responses are acquired from displacement
and acceleration sensors at damper location and converted into digital data by NI DAQ Card-6062E.
1414Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
Control algorithms:
to calculate the command voltage input
• Passive-mode cases
- passive-off (v=0V),
- passive-on (v= 1.4V)
- other passive-modes (v= 0.6V, 1.0V, 1.1V, 1.2V, 1.3V)
1515Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
• Semiactive control cases (Jansen and Dyke 2000)
- Clipped-optimal control algorithm
where, Vmax=1.4V, Fd ci= the desired control force, and
Fd = the measured control force
- Control based on Lyapunov stability theory
where, z = the state vector, and
P = the matrix to be found using the Lyapunov equation
)}({max ddcidi FFFHVv
))((max dT
i PBFzHVv
(2)
(3)
1616Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
- Maximum energy dissipation algorithm
where, vd = the velocity at the damper location
- Modulated homogeneous friction algorithm
)(max ddi FvHVv
|)|(max ddi FFHVvn
)(tiPgF ndn
P[i(t)] = i(t-s),
where s = {min x0: i(t-x)=0}
(4)
(5)
1717Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
Experimental Results
Displacement in free vibration
Time (sec)
Dis
plac
emen
t (m
)
1818Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
Damping ratios for verification of performances
• The amplitude-dependent damping ratios are calculated by
the Hilbert transform-based identification method
(Duan et al. 2002)
1919Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
Damping ratios in the passive-mode casesD
ampi
ng r
atio
(%
)
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0 5 10 15 20 25
passive V=1.4 passive V=1.3 passive V=1.2passive V=1.1passive V=1.0passive V=0.6passive V=0.0uncontrolled
Amplitude (mm) at the location of 10.2 m away from the bottom support
2020Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
Damping ratios in the semiactive control cases
Amplitude (mm) at the location of 10.2 m away from the bottom support
Dam
ping
rat
io
(%)
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
3 5 7 9 11 13 15 17
Passive offPassive onClipped optimalLyapunovMHFMEDA
2121Structural Dynamics & Vibration Control Lab., KAIST, KoreaStructural Dynamics & Vibration Control Lab., KAIST, Korea
Conclusions
Semiactive control systems significantly improve the
mitigation of stay cable vibration over the uncontrolled
and the passive-off cases.
Semiactive control systems significantly improve the
mitigation of stay cable vibration over the uncontrolled
and the passive-off cases.
The Modulated homogeneous friction algorithm shows
nearly the same performance as the passive-on case.
The Modulated homogeneous friction algorithm shows
nearly the same performance as the passive-on case.
The performance of MR damper-based control systems for suppressing vibration of stay cables is experimentally verified.
The performance of MR damper-based control systems for suppressing vibration of stay cables is experimentally verified.
The control based on Lyapunov stability and the clipped-
optimal control show slightly better performance than
the passive-on case.
The control based on Lyapunov stability and the clipped-
optimal control show slightly better performance than
the passive-on case.