Accession Number : AD0483472

Title :   STRUCTURE-MEDIUM INTERACTION IN A NONELASTIC MEDIUM.

Descriptive Note : Final rept. 6 Nov 64-30 Nov 65,

Corporate Author : SCIENCE ENGINEERING ASSOCIATES INC SAN MARINO CA

Personal Author(s) : Karlsson, Thorbjorn ; Ko, William L.

Report Date : MAY 1966

Pagination or Media Count : 148

Abstract : The interaction of a plane dilational wave with a curcular cylindrical inclusion buried in an elastoplastic medium is studied. The cylindrical inclusion is rigid and stationary and of infinite length. The surrounding elastoplastic medium exhibits a bilinear stress-strain relationship concave towards the strain axis. The incident plane dilatational wave travels in a direction perpendicular to the axis of the cylinder and has the form of a step wave. The magnitude of the wave is such that the stresses behind the step correspond to yielding of the medium. This will cause yielding in the medium as the wave is reflected off the cylindrical obstacle. Using Kirchhoff's method of retarded potentials, solutions are obtained for this problem in terms of surface and volume integral equations. These equations are solved by means of finite-difference approximations of the integrals. A computer program was written to evaluate the boundary stresses as the incident wave engulfs half of the cylindrical inclusions. Numerical results obtained for wave front stresses show excellent agreement with those obtained using high-frequency wave front analysis. (Author)

Descriptors :   (*UNDERGROUND STRUCTURES, WAVE PROPAGATION), (*STRUCTURES, STRESSES), SHOCK WAVES, ELASTIC SCATTERING, APPROXIMATION(MATHEMATICS), ACOUSTICS, ELASTIC PROPERTIES, ELASTIC SHELLS, FOURIER ANALYSIS, INTEGRAL TRANSFORMS, PROPAGATION, EQUATIONS OF MOTION, BOUNDARY VALUE PROBLEMS, COMPUTER PROGRAMMING, DIFFRACTION, NUMERICAL ANALYSIS, DEFORMATION, PLASTIC PROPERTIES, CYLINDRICAL BODIES, MECHANICAL WAVES.

Subject Categories : Structural Engineering and Building Technology
      Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE