Accession Number : ADA293042

Title :   An Inverse Method to Measure the Axial Modulus of Composite Materials Under Tension.

Descriptive Note : Final rept.,

Corporate Author : NAVAL UNDERSEA WARFARE CENTER NEWPORT DIV RI

Personal Author(s) : Hull, Andrew J.

PDF Url : ADA293042

Report Date : 03 JAN 1995

Pagination or Media Count : 22

Abstract : In this report, an inverse method is developed to measure the axial modulus of materials subjected to tensile loads. The approach is intended for use on long composite structures whose modulus is frequency dependent. The governing differential equations of a laboratory test configuration are solved and then inverted at three locations that correspond to sensor transfer functions. These three equations are next combined in such a way that the complex-valued axial modulus is equal to a function of the measured data and the known system parameters. This expression is a closed-form measurement of the modulus at each test frequency. An experiment is included to validate the method. Comparisons between the transfer function data and the model expressed with the measured modulus are in close agreement. (MM)

Descriptors :   *COMPOSITE MATERIALS, *TENSILE STRESS, TRANSFER FUNCTIONS, STIFFNESS, DISPLACEMENT, EIGENVALUES, DIFFERENTIAL EQUATIONS, SPECIAL FUNCTIONS(MATHEMATICS), AXIAL LOADS.

Subject Categories : Laminates and Composite Materials
      Numerical Mathematics

Distribution Statement : APPROVED FOR PUBLIC RELEASE