STRESS WAVES IN A SOIL-FILLED CYLINDRICAL SHELL.

Abstract

An approximate solution to the problem of transient longitudinal wave propagation in a semi-infinite cylindrical body of elasto-plastic material restrained radially by a stacked-ring shell and subjected to a normal pressure at the end is obtained by a Galerkin technique using the radial coordinate as an expansion parameter. In order to get equations applicable to numerical computations the expansions are truncated to the leading term in each variable. This truncation creates a mathematical problem when elastic and plastic regions occur along the same radial line. A finite-difference scheme is used to solve the differential equations resulting from application and truncation of the Galerkin expansion. A special method for handling the boundary between elastic and plastic regions along the same radial line is developed in conjunction with this numerical solution. Numerical results of the finite-difference scheme are presented for several variations in such parameters as shell stiffness and material constants. For the purpose of evaluating the results of the truncation to the leading term in each expansion, the analogous problem is formulated for a linear inviscid fluid and solved twice, once with a truncation to the first term and once carrying two terms in each expansion. The numerical results are presented for these two solutions so that the change in the solution caused by the truncation can be evaluated. (Author)

Document Details

Document Type
Technical Report
Publication Date
May 01, 1970
Accession Number
AD0709726

Entities

People

  • Hans H. Bleich
  • John Kovarna

Tags

DTIC Thesaurus Topics

  • Bodies
  • Boundaries
  • Computations
  • Cylindrical Bodies
  • Differential Equations
  • Equations
  • Materials
  • Mathematics
  • Mechanical Properties
  • Physical Properties
  • Stiffness
  • Stress Waves
  • Truncation
  • Wave Propagation
  • Waves

Fields of Study

  • Mathematics

Readers

  • Calculus or Mathematical Analysis
  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Structural Dynamics.