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http://dx.doi.org/10.5000/EESK.2008.12.1.043

Identifying Strain Associated with Damping Ratio from Tosional Test Using a Combined Damping Model  

Bae, Yoon-Shin (유타주립대학교)
Publication Information
Journal of the Earthquake Engineering Society of Korea / v.12, no.1, 2008 , pp. 43-55 More about this Journal
Abstract
The complexity of determining strain associated with shear modulus and damping ratio in torsional tests has been resolved by means of several approaches. Particularly, the modified equivalent radius approach is adequate to when generating the plots of equivalent radius ratio versus strain more effectively over any range of strains in resonant column and torsional shear (RC/TS) tests. The modified equivalent radius approach was applied for hyperbolic, modified hyperbolic, and Ramberg-Osgood models in evaluating damping ratio. Results showed that using a single value of equivalent radius ratio based on conventional equivalent radius approach is not appropriate. A new model was developed to consider the soil damping behavior at small strains as well as hysteretic damping and it was attempted to determine adjustments are required in evaluating strain associated damping when combining the two damping components.
Keywords
damping ratio; nonlinear soil model; strain calculation;
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