FOURIER-TRANSFORM TECHNIQUE FOR MEASURING TERMINATING IMPEDANCES.
Abstract
The mechanical impedance of a foundation depends, in part, on the characteristics of the column attached to it. For this reason it is important to have a technique to find that mechanical impedance with the column in place; this requirement rules out direct measurement with an impedance head. This study was made to determine the usefulness of a transient loading technique for measuring the mechanical impedance of a complex termination. The method determines the impedance at the end of an elastic bar from the Fourier Transforms of pulse shapes in the bar. Experimental results for a simple termination show that this technique can be used to measure the impedance of a lumped parameter system. However, comparison between transient loading measurements and direct measurements with an impedance head for a more complex termination show that not enough frequency information can be obtained to determine its impedance accurately enough. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1964
- Accession Number
- AD0634745
Entities
People
- L. E. Wittig
- R. Plunkett
Organizations
- University of Minnesota