Accession Number : ADA300105

Title :   Micromechanics Modeling and Analysis of Haversian Compact Bone Tissue as a Fiber Reinforced Composite Material.

Descriptive Note : Annual rept. 1 Apr 92-31 Dec 94,

Corporate Author : TEXAS A AND M UNIV COLLEGE STATION DEPT OF MECHANICAL ENGINEERING

Personal Author(s) : Hogan, Harry A.

PDF Url : ADA300105

Report Date : MAY 1995

Pagination or Media Count : 38

Abstract : Haversian compact bone tissue is being studied theoretically and experimentally to characterize its behavior as a fiber reinforced composite material with the aim of biomimicking its salient features. Analytical and finite element based composite micromechanics techniques have been developed and evaluated for theoretical modeling of structure/property relationships. two-dimensional finite element models of material representative volume elements have been used to predict variations in macroscopic mechanical properties with porosity, constituent properties, and fiber/matrix interface conditions. Mori-Tanaki effective medium methods have also been examined. Haversian compact bone possesses a distinct interphase' material surrounding each osteon called the cement line. The role and properties of the cement line are of particular interest for possible biomimicking. Mechanical testing of bone specimens is accompanying the theoretical work to provide data for verification and model improvement. Anisotropic elastic moduli have been measured using through-transmission ultrasound. Longitudinal tensile strength and elastic modulus have been determined from quasi-static tensile testing. In addition, dynamic mechanical testing has been initiated to measure viscoelastic properties. (storage & loss moduli, loss factor). Testing results are also being correlated with quantitative microstructural measures. The parameters of interest include bulk density (wet & dry), mineralization (ash), porosity, osteon area fraction, and total cement line perimeter (per unit area). Additional dynamic testing is continuing to more definitively determine the influence of the cement line on properties.

Descriptors :   *TISSUES(BIOLOGY), *COMPOSITE MATERIALS, *FIBER REINFORCED COMPOSITES, *MICROMECHANICS, *BONES, TEST AND EVALUATION, MATHEMATICAL MODELS, DENSITY, MECHANICAL PROPERTIES, TENSILE STRENGTH, MICROSTRUCTURE, VERIFICATION, MODELS, TWO DIMENSIONAL, FINITE ELEMENT ANALYSIS, VISCOELASTICITY, MODULUS OF ELASTICITY, MOISTURE CONTENT, POROSITY, CEMENTS, ANISOTROPY, TENSILE TESTERS, DYNAMIC TESTS, MINERALIZATION.

Subject Categories : Laminates and Composite Materials
      Medicine and Medical Research

Distribution Statement : APPROVED FOR PUBLIC RELEASE