RESPONSE OF ELASTIC STRUCTURES TO DETERMINISTIC AND RANDOM EXCITATION.

The fundamental classical theory governing the response of linear distributed elastic structures to deterministic and to random excitation. A review is made of the basic dynamics theory for discrete and distributed systems when the excitation is deterministic. Integral expressions are derived for the mean square value and correlation functions for the response of an arbitrary linear elastic structure subjected to stationary random loading. The value and limitations of using classical theory as a tool for predicting structural vibrations in typical flight vehicles are explored. The theoretical results for distributed structures subjected g stationary random excitation are noted to yield complicated analytical expressions even for uniform beams. The direct extension of the shown theoretical results to include typical flight structures, although technically accurate, is not considered practical. The derivation procedures and results can be used as a basis for forming statistical parametric techniques for approximating the response behavior of distributed systems to random excitation. Several existing techniques reflecting compromises in theoretical rigor are discussed and subject areas for future study are noted. Author