Accession Number : ADA193559

Title :   A Technique for Measuring Area under a Curve.

Descriptive Note : Final rept.,

Corporate Author : ARMY ARMAMENT RESEARCH DEVELOPMENT AND ENGINEERING CENTER WATERVLIET NY BENET LABS

Personal Author(s) : Underwood, J H

PDF Url : ADA193559

Report Date : Mar 1988

Pagination or Media Count : 12

Abstract : Measurement of the area under a curve is often the most direct way to determine the energy of a mechanical system. Area measurements are now routinely used in fracture mechanics testing as part of the standard test method for the J-integral fracture toughness. Vossoughi recently described a method for measuring the area under a curve, based on the weight of a template of the area. The technique suggested here is a simple geometric procedure suited to the relatively regular shapes of elastic-plastic load versus displacement plots of the type shown by curve OAB in Figure 1. This curve is typical of those obtained from tensile strength and fracture toughness tests of metals. Keywords: Plane geometry, Load-deflection curves, Trapezoids.

Descriptors :   *AREA COVERAGE, *MEASUREMENT, *MECHANICAL COMPONENTS, *PLANE GEOMETRY, DISPLACEMENT, ELASTIC PROPERTIES, FRACTURE(MECHANICS), GEOMETRY, J INTEGRALS, METALS, PLASTIC PROPERTIES, PLOTTING, SHAPE, STANDARDIZATION, TEMPLATES, TENSILE STRENGTH, TEST AND EVALUATION, TEST METHODS, TOUGHNESS, WEIGHT

Subject Categories : Numerical Mathematics

Distribution Statement : APPROVED FOR PUBLIC RELEASE