Lagrangian Analysis.

Abstract

Estimation of stress and strain paths followed in in situ, high explosive field tests may be obtained from direct inversion of the velocity and stress histories measured. When the field tests are designed as one-dimensional tests (planar, cylindrical, or spherical), a technique commonly called Lagrangian Analysis of Stress and Strain (LASS) has been employed. The results from recent LASS analysis of dry soils have not been self-consistent nor yielded estimates which have been shown to be better than currently arrived at by lab tests and parametric calculations. This report develops another method of LASS which deviates somewhat from earlier path line and traveling wave formulations. Equations for the new method are derived. Estimates due to instrumentation inaccuracy are examined. Methodological errors in estimation of strains and stress bounds are also investigated. While this paper does not address all the possible sources of inconsistency, it will point out many which have not received attention before. Specifically, errors due to instrumentation inaccuracy; and methodological errors in estimation of strains and stress bounds. Keywords: Material models; Lagrangian analysis; Constitutive relationships.

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Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1987
Accession Number
ADA194710

Entities

People

  • Eric J. Rinehart
  • George M. Lloyd

Tags

Communities of Interest

  • Counter WMD
  • Ground and Sea Platforms
  • Space
  • Weapons Technologies

DTIC Thesaurus Topics

  • Accuracy
  • Air Force
  • Explosives
  • Field Tests
  • High Explosives
  • Instrumentation
  • Materials
  • Measurement
  • National Security
  • Radial Stress
  • Security
  • Stresses
  • Test And Evaluation
  • United States European Command
  • War Colleges
  • Warfare
  • Wave Propagation

Readers

  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Materials Science (Mechanical Engineering).
  • Regression Analysis.