Accession Number : AD0617405

Title :   INTERACTION OF PLANE ELASTIC WAVES WITH A THICK CYLINDRICAL SHELL.

Descriptive Note : Final rept. for Dec 62-Mar 65,

Corporate Author : ILLINOIS UNIV URBANA DEPT OF CIVIL ENGINEERING

Personal Author(s) : Paul,S. ; Robinson,A. ; Ali-Akbarian,M.

Report Date : JUN 1965

Pagination or Media Count : 109

Abstract : A method is presented for computing stresses in the vicinity of a lined cylindrical cavity in an infinite, elastic, isotropic, homogeneous medium as it is enveloped by a plane stress wave of dilatation traveling in a direction perpendicular to the axis of the cavity. The liner, which may be thick, is considered as a second elastic medium. Both the incident stress and the perturbations in the stress field are represented by Fourier series where the coefficients are functions of radius and time. These coefficients represent two dimensional traveling-wave solutions and are found by solving sets of coupled integral equations of the Volterra type. A computer program was written to carry out the numerical computations. Hoop stresses in the liner and in the medium at the linermedium interface were computed at various angles around the opening for a plane longitudinal step wave. It was found that the maximum dynamic stresses occur on a diameter which is perpendicular to the direction of wave propagation, and that the dynamic stresses are sensitive to variation of the ratio of thickness of the liner to its radius, and stiffness of the liner relative to that of the medium. Further studies were then made to determine the variation of maximum hoop stresses in the liner and medium with these parameters. The maximum dynamic stresses were compared with the corresponding static values. In addition, the effect of decay and rise time of the incident on the maximum hoop stress was investigated. (Author)

Descriptors :   (*STRESSES, UNDERGROUND STRUCTURES), (*UNDERGROUND STRUCTURES, STRESSES), MECHANICAL WAVES, CYLINDRICAL BODIES, POTENTIAL THEORY, FOURIER ANALYSIS, SERIES(MATHEMATICS), BOUNDARY VALUE PROBLEMS

Distribution Statement : APPROVED FOR PUBLIC RELEASE