Accession Number : ADA330153

Title :   Variability in Geometry and Imperfections of Surface Ship Structural Scantlings.

Descriptive Note : Final rept.,

Corporate Author : NAVAL SURFACE WARFARE CENTER CARDEROCK DIV BETHESDA MD

Personal Author(s) : Hess, Paul E., III ; Ayyub, Bilal M.

PDF Url : ADA330153

Report Date : APR 1997

Pagination or Media Count : 102

Abstract : Random behavior of strength variables of a structure can cause the strength of the structure to vary beyond acceptable levels. The design strength is based on nominal values for variables such as yield stress of the material, plate thickness, modulus of elasticity, and so forth. The actual values of these variables are often different from the nominal, or design values. Understanding the randomness of the basic strength variable behavior allows the designer to account for this in the design strength of the structure. The basic structural strength variables may be classified into material variables, such as yield strength and ultimate strength, and geometry or construction variables, such as plate thickness and stiffener height. The objective of this study is to quantify the randomness or uncertainty found in the geometric variables used in the analysis and design of surface ship structures. The bulk of the data used in this study are for U.S. Navy ships. Additional data is provided for U.S. Coast Guard and commercial vessels. The results of this study can be used in the development of reliability based design criteria, tolerance limits, and the assessment of uncertainty in strength predictions.

Descriptors :   *STRUCTURAL ANALYSIS, *MARINE ENGINEERING, *NAVAL ARCHITECTURE, STRESSES, UNCERTAINTY, NAVAL VESSELS, STIFFENING, STRENGTH(MECHANICS), CONSTRUCTION, STRENGTH(GENERAL), TOLERANCE, GEOMETRY, STATISTICAL ANALYSIS, YIELD STRENGTH, MERCHANT VESSELS, COAST GUARD SHIPS, SHIP STRUCTURAL COMPONENTS.

Subject Categories : Marine Engineering

Distribution Statement : APPROVED FOR PUBLIC RELEASE