Chapter II.0
Introduction

Four classes specific to Classical Laminate Analysis calculations have been defined in FeResPost module:

• The “ClaDb” class allows the definition of composite databases used to store the definition of composite materials, laminates and loadings. This class is presented in Chapter II.2.
• The “ClaMat” class allows the definition and manipulation of materials. This class is presented in Chapter II.3.
• The “ClaLam” class allows the definition and manipulation of laminates. This class is presented in Chapter II.4.
• The “ClaLoad” class allows the definition and manipulation of loadings to be applied to laminates. This class is presented in Chapter II.5.

Throughout the composite manual pages, the concept of identifier is often used. An identifier can be:

• An Integer,
• A String,
• Or an Array of two elements (an integer and a String).

This concept is introduced to provide a general way to identify and access materials, laminates or loads stored in a ClaDb object. Indeed, the methods used to access those data must be compatible with several software (ESAComp or finite element solvers...). As entities manipulated by these software are sometimes identified by integers, sometimes by strings and sometimes by both an integer and a String, this peculiar way to identify the entities in a ClaDb object had to be developed. For example, if a ClaLam object has been stored in a ClaDb, it can be retrieved with:

Note however that the identifier used to retrieve lam2 must match exactly the identifier of lam1. For example, if lam1 has [5,"panel1"] identifier, only the third “getLaminateCopy” statement works.

This leads us to a last remark about interfaces with other software. The composite classes are meant to be used with the rest of FeResPost. Among other things, it allows:

• To produce layered results automatically, using the definition of laminates and, for example, Results corresponding to in-plane forces and bending moments in 2D elements,
• To calculate the corresponding failure indices, strength ratios and reserve factors, all these being instances of the FeResPost::Result class.
• ...

The composite capabilities programming is based on the Classical Laminate Analysis as presented widely in literature. The programmer based its developments on [Gay97]. For the in-plane and flexural parts of laminate response, the approximations done in the development of equations are common to what has been found in the rest of literature. On the other hand, few references have been found about the out-of-plane shear behavior of laminates. In [Gay97], this aspect of laminate analysis is presented with a few assumptions. For example, Gay assumes a mirror symmetry of the laminate. This is obviously not a characteristic of all laminates. Therefore, the out-of-plane shear responses calculated by composite classes should be used with care.

More information about the conventions used for FeResPost composite calculations are given in Chapter II.1.