Accession Number : AD0751237

Title :   Response of Viscoelastic Materials to Random Loading.

Descriptive Note : Masters thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OHIO SCHOOL OF ENGINEERING

Personal Author(s) : Valentine,Michael L.

Report Date : AUG 1970

Pagination or Media Count : 76

Abstract : A method was developed to simulate the random loading history that a structure experiences in service. This method produces a random load that duplicates the irregularity factor, the power spectral density, and the load spectrum of the service load. An experimental investigation was conducted to determine the response of viscoelastic materials to random loading histories. The random loading histories were generated by the method mentioned above. Experiments were conducted on two different materials. One specimen was made of quasi- isotropic fiberglas-epoxy composite material, and the other was an SBR rubber cylinder. The dynamic compliance for each material was determined by viscoelastic interconversion of data from creep tests. Two random vibration experiments at different irregularity factors were conducted on each specimen. The experimental results were compared to results predicted from random vibration theory and linear viscoelasticity. The experimental results for both specimens were in very good agreement with the predicted results. (Author-PL)

Descriptors :   (*VISCOELASTICITY, TEST METHODS), (*COMPOSITE MATERIALS, VISCOELASTICITY), LOADS(FORCES), SIMULATION, RUBBER, VIBRATION, NUMERICAL ANALYSIS, THESES, COMPUTER PROGRAMS

Subject Categories : Laminates and Composite Materials
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE