JEC COMPOSITES MAGAZINE - Issue #85 - November/December 2013 - 54

simulation

A novel tool for composite
beam computations
Using composite beams is a real trend today in many engineering applications. However, the mechanical behaviour of
such composite structures is not so easy to understand, to
predict, to compute and therefore to design. A fully 3D finite
element analysis is expensive and there is a real need for an
efficient numerical tool devoted to the simulation of composite beams, and that is also easy to use by engineers and
technicians. The CSection & CBeam package provides such
a tool; it can really help R&D engineers to design composite
sections and beams.

he design of homogeneous
beams is well understood
nowadays and the calculation
methods available for engineers are
sufficient to meet the requirements
of current mechanical engineering.
In contrast, composite beams are not
so easy to design. Their mechanical
behaviour is much more difficult to
understand and to predict. Laminated
composite beams are known to exhibit
complex phenomena such as coupled
deformations arising from the orthotropic nature of the layers and from
the stacking sequences. And the situation is more complex when, to reduce
cost and weight, thin-walled open/
closed sections are involved.
Detailed structural models are then
essential in order to fully exploit such
specific effects in the design phase.
In addition to the structural level, detailed 3D stress analysis is of practical

relevance for composites and especially the inter-laminar stresses which
may result in delamination and failure
of the laminates.
Using composite beams is a real trend
in many engineering applications, but
using 3D finite element analysis to
facilitate design is costly. This trend
calls for the development of efficient
tools, suitable for the analysis of
beams exhibiting 3D effects, for which
the classical beam theory assumptions
are no longer valid. The CSection &
CBeam package provides such a tool.

A numerical tool to help design
The CSection & CBeam package was
developed on the MATLAB platform.
It consists of two complementary numerical tools - CSection and CBeam
- devoted to the computation of
homogeneous or composite sections
and beams. CSection computes the
Mechanical Characteristics of the Section (MCS) and CBeam uses the MCS
to simulate the 3D elastic behaviour

54 jec composites magazine / No85 November - December 2013

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PRoFessoR, stRuctuRal mechanics
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of the beam subjected to any loading
and boundary conditions.
The graphical user interface is designed to be easily used by engineers
or technicians and the CPU time is
quite low on a common PC (a few
seconds).
The cost-effective 1D computations
of CBeam result in 3D displacements
and 3D stresses really comparable
to those obtained by fully 3D FEM
computations in the major interior
part of the beam, even if the slenderness is small.
CSection & CBeam can really help
to design and optimize composite
sections and beams, especially when
working with strongly anisotropic
materials and/or thin-walled open/
closed profiles.
This tool can also be used to interpret tests conducted on composite
materials. Indeed, samples commonly
look like (short) beams. These material tests are not homogeneous but

JEC COMPOSITES MAGAZINE - Issue #85 - November/December 2013

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #85 - November/December 2013