ETD Electronic Theses & Dissertations
About ETD Search the ETD Database    

 

 

Full text available full text is available online.

Document ID:CEE2002-007
Document Type:Thesis
Author:Perrine Parrod
E-mail Address:
URN:
Title:A LATTICE MODEL FOR FIBROUS MATERIALS
Degree:M.S.
Department:Civil and Environmental Engineering
Committee Chair:Eric Landis, Associate Professor of Civil and Environmental Engineering
Chair's E-mail:
Committee Members:William Davids, Assistant Professor of Civil and Environmental Engineering; Vincent Caccese, Associate Professor of Mechanical Engineering
Subjects:Fibers; Microstructure
Date of Defense:2002
Availability:

Abstract

The difficulties of describing the material properties of wood come from its complexity, anisotropy and heterogeneity that make fracture, damage and failure hard to model. This research deals with an innovative modeling approach that is similar to one that has been used for concrete. Instead of using classical continuum-based finite element method, which has already been used extensively in the past and has not led to conclusive results, lattice models are utilized. The microstructure can be discretized in lattice of beam or bar elements. We choose to model wood fiber bundles as beam elements, and inter-fiber adhesion with a series of transverse and diagonal springs. Material properties (Young modulus and strength) for each of these elements are statistically assigned using a Monte-Carlo simulation. For the simulation, we choose Displacement control. At each step of the calculation, a displacement increment is applied to the structure, and the resulting forces are calculated. As damage occurs in the material, elements are progressively removed. The studied specimens are subjected to several load cases: tension parallel-to-grain with and without notch, tension perpendicular-to-grain, shear parallel-to-grain, bending and compression parallel-to-grain. With this method, we manage to model both loaddeformation response and damage characteristics of the material.


View in PDF Format

Parrod, Perrine, University of Maine, CEE2002-007

 

Fogler Digital Library
How to submit your electronic thesis or dissertation
UM Graduate School Fogler Library The University of Maine