Cable Modal Parameter Identification. II: Modal Tests
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VIEW THE REPLYPublication: Journal of Engineering Mechanics
Volume 135, Issue 1
Abstract
The cable dynamic stiffness describes the load–deformation behavior that reflects the cable intrinsic dynamic characteristics. It is defined as a ratio of response to excitation and represents a very similar frequency response property to the frequency response function (FRF). Therefore, by fitting both analytical cable dynamic stiffness and measured frequency response function, the modal parameters of cables can be identified. Based on the simplified cable dynamic stiffness proposed in the first part of the two-part paper, this paper presents a cable dynamic stiffness based procedure to identify the cable modal parameters (natural frequencies and damping ratios) by modal tests. To carry out the curve fitting, a nonlinear least-squares approach is used. A numerical simulation example is first introduced to illustrate the feasibility of the proposed method. Further, a series of cable modal tests are conducted in the laboratory with different cable tensions and the frequency response functions are measured accordingly. A number of issues related to the cable modal tests have been discussed, such as accelerometer arrangement and excitation placement, frequency resolution, windowing, and averaging. It is demonstrated that the cable modal parameters can be effectively identified by using the proposed method through the cable modal tests.
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Acknowledgments
Financial support from the Natural Science Foundation of China (NSFC) under Grant Nos. 50378021 and 50678173 is greatly acknowledged. The first writer also acknowledges the financial support from the Program for New Century Excellent Talents (NCET) in University, Ministry of Education, People’s Republic of China.
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Information & Authors
Information
Published In
Journal of Engineering Mechanics
Volume 135 • Issue 1 • January 2009
Pages: 51 - 61
Copyright
© 2009 ASCE.
History
Received: May 18, 2007
Accepted: Jul 15, 2008
Published online: Jan 1, 2009
Published in print: Jan 2009
Notes
Note. Associate Editor: Lambros S. Katafygiotis
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