A Comparison of Damping Ratio Analysis for Dynamic Foundation Vibration

Abstract eng:
Damping ration measurement method of a foundation was studied theoretically and experimentally based on the corresponding Chinese testing and design Codes. It shows that there is a relatively large difference between numerical results of Codes, approximate formulae of elastic half-space analytical solution, and the practical testing result. Therefore, six-degree-freedom time histories of the center of mass of a foundation are calculated from three-component vibration curves of some points on the foundation surface to be selected as the timehistory of damping ratio calculating of subsoil. And also, to reduce the difference mentioned above, influence of window function on the subsoil damping ratio of a massive concrete foundation is analyzed based on logrithmic decrement method in the time domain and point-peak method in the frequency domain. It shows that damping ratio decreases as the smoothing times increases in the time domain, and on the contrary in the frequency domain.

• Export as: BibTeX | MARC | MARCXML | DC | EndNote | NLM | RefWorks
• Add to your basket