Accession Number : ADA112054

Title :   Determination of Structural Reliability Using a Flaw Simulation Scheme

Descriptive Note : Final rept.

Corporate Author : ARMY MATERIALS AND MECHANICS RESEARCH CENTER WATERTOWN MA

Personal Author(s) : Neal, Donald M ; Mason, Donald S

PDF Url : ADA112054

Report Date : Oct 1981

Pagination or Media Count : 22

Abstract : This paper describes structural reliability developed an assumed flaw simulation scheme combined with an idealized linear elastic fracture mechanics model. In the reliability computation, it has been demonstrated that application of this scheme can provide a sensitivity analysis in relation to flaw detection capabilities. To demonstrate the versatility of the method, reliability numbers were obtained for both a simply loaded fragmentation shell and an antitank projectile subjected to a complex stress state. The flaw simulation scheme results are compared to corresponding reliability determinations from conventional Weibull and Warner stress-strength diagram methods. Both the weakest link and series-parallel system are evaluated for desirability in estimating structural reliability. The weakest link approach, which introduces reliability independence between elements, will thereby describe a much more conservative reliability estimate than the series-parallel system which requires at least two adjacent elements to fail in order to have structural failure. Examining the reliability computation for both structures as a function of assumed minimum detectable crack sizes indicated the importance of determining relatively small cracks to obtain acceptable reliability.

Descriptors :   *DEFECTS(MATERIALS), *DETERMINANTS(MATHEMATICS), *FINITE ELEMENT ANALYSIS, *FRACTURE(MECHANICS), *STRUCTURAL PROPERTIES, ANTITANK WEAPONS, ELASTIC PROPERTIES, FAILURE(MECHANICS), MONTE CARLO METHOD, PROJECTILE CASES, RELIABILITY, SIMULATION, STRENGTH(MECHANICS), STRESS ANALYSIS, WEIBULL DENSITY FUNCTIONS

Subject Categories : Statistics and Probability
      Ammunition and Explosives
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE