Accession Number : ADA324899

Title :   A New Approach to Structural Reliability in Fatigue Failure.

Descriptive Note : Interim rept. 1 Apr 96-31 Mar 97,

Corporate Author : CALIFORNIA UNIV SAN DIEGO LA JOLLA DEPT OF APPLIED MECHANICS AND ENGINEERING SCIENCES

Personal Author(s) : Nemat-Nasser, Sia ; Zarka, Joseph

PDF Url : ADA324899

Report Date : 31 MAR 1997

Pagination or Media Count : 4

Abstract : The project objective is to develop formalism for assessing fatigue fracture of welded parts of ship structures based on a newly developed automatic Learning Expert System (L.E.S.), using extensive knowledge of material characteristics, experimental results, and results obtained through computational simulations. Any study of the welds on a ship structure must take into account the uncertainties and random characteristics of the loading, as well as the fatigue lifetime of the welds. Due to the stochastic nature of the loads, the available deterministic approaches are not sufficient to give a reliable evaluation of the structural safety. Although there has been some effort to fill this gap by probabilistic approaches, these are yet of limited usefulness because of the limited available databases. The research project will ultimately demonstrate the applicability and effectiveness of L.E.S to this class of engineering mechanics problems. As the first and fundamental step in this project, it is necessary to build a relevant database. Experimental and field data has secured from Navy research centers, and through collaboration with scientists working in this general area. Additional data has been obtained from literature searches.

Descriptors :   *WELDS, *RELIABILITY, *FATIGUE(MECHANICS), *SHIP STRUCTURAL COMPONENTS, DATA BASES, COMPUTERIZED SIMULATION, FRACTURE(MECHANICS), SAFETY, EXPERT SYSTEMS, LEARNING, AUTOMATIC.

Subject Categories : Couplers, Fasteners, and Joints
      Mechanics
      Marine Engineering

Distribution Statement : APPROVED FOR PUBLIC RELEASE