Hooke orthotropic

In Section 2.2, the stress-strain relations (generalized Hooke s law) for anisotropic and orthotropic as well as isotropic materials are discussed. These relations have two commonly accepted manners of expression compliances and stiffnesses as coefficients (elastic constants) of the stress-strain relations. The most attractive form of the stress-strain relations for orthotropic materials involves the engineering constants described in Section 2.3. The engineering constants are particularly helpful in describing composite material behavior because they are defined by the use of very obvious and simple physical measurements. Restrictions in the form of bounds are derived for the elastic constants in Section 2.4. These restrictions are useful in understanding the unusual behavior of composite materials relative to conventional isotropic materials. Attention is focused in Section 2.5 on stress-strain relations for an orthotropic material under plane stress conditions, the most common use of a composite lamina. These stress-strain relations are transformed in Section 2.6 to coordinate systems that are not aligned with the principal material... 

For a unidirectional laminate the elastic stress-strain relations define an orthotropic material for which the generalized form of Hooke s Law, relating the stress o to the strain e,... 

As wood is orthotropic, each behavior law involves nine independent terms. In fact, it is more common to define the inverse of that, for the case of linear elasticity, leads to the generalized Hooke s law ... 

The most prevalent and widely developed constitutive connections of polymers between strain and stress are dealt with in linear elasticity by applying the generalized form of Hooke s law which is presented in Chapter 4 for anisotropic solids of different symmetry classes starting with orthotropic solids and progressing up to isotropic solids. Here and in the following chapters we shall develop only the connection for isotropic solids, which is the most useful one and most often is quite sufficient in development of concepts. 

Orthotropic Lamina Hooke s Law in Principal Material Coordinates... 

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