Effects of Radiation Damping on Vibration of a Shallow-Buried Rectangular Structure.

Abstract

Radiation damping from shallow-buried structures of rectangular cross-section was analyzed by means of an elastic, finite element model. The results show that radiation damping increases with the stiffness of backfill, which is consistent with results previously obtained for a buried arch. Implications are examined of including a viscous damping mechanism to simulate radiation damping in nonlinear single-degree-of-freedom models of the roof slab. In the examples considered, including radiation damping up to 20% of critical (based on the stiffness of the slab in the elastic-cracked regime), reduces calculated peak displacements to as little as one-half of the magnitude as calculated by SDOF models without damping. To explain the dependence of radiation damping on deformational mode number, an exact analysis of a cylindrical elastic, plane strain section in an infinite elastic domain was performed. As expected, the findings indicate that higher radiation damping is associated with the lower modes. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1978
Accession Number
ADA061442

Entities

People

  • G. L. Wojcik
  • J. Isenberg

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies
  • Space
  • Weapons Technologies

DTIC Thesaurus Topics

  • Air Force
  • Backfills
  • Civil Engineering
  • Construction
  • Engineering
  • Engineers
  • Failure Mode And Effect Analysis
  • Frequency
  • Frequency Shift
  • Geometry
  • Materials
  • Measurement
  • Modal Analysis
  • Reinforced Concrete
  • Resonant Frequency
  • Transient Response Analysis
  • War Colleges

Fields of Study

  • Physics

Readers

  • Geotechnical Engineering.
  • Nuclear and Radiation Engineering.
  • Structural Dynamics.