Citation
Abstract
An extensive dynamic analysis for the new JPL 70-meter antenna structure is presented, Analytical procedures are based on the normal mode decomposition, which include damping and special forcing functions. The dynamic response can be obtained for any arbitrarily selected point on the structure. A new computer program for computing the time-dependent, resultant structural displacement, summing the effects of all participating modes, was developed also, Program compatibility with natural frequency analysis output was verified. The program was applied to the JPL 70-meter antenna structure and the dynamic response for several specially selected points was computed. Seismic analysis of structures, a special application of the general dynamic analysis, is based also on the normal modal decomposition, Strength specification of the antenna, with respect to the earthquake excitation, is done by using the common response spectra, The results indicated basically a safe design under an assurned 5% or more damping coefficient. However, for the antenna located at Goldstone, with more active seismic environment, this study strongly recommends an experimental program that determines the true damping coefficient for a more reliable safety check.
Details
- Volume
- 42-83
- Published
- November 15, 1985
- Pages
- 12–25
- File Size
- 791.9 KB