A durability assessment is used to evaluate the
strength/life of a product or structure when
subjected to a specific usage. This can help
determine if the product or structure can stand up
to the use for which it was originally designed and
still function as intended. It can also be used to
evaluate the consequences of
 a new service
environment,
a change in
materials
a new
fabrication process, or
a change in
design geometry, etc.
In a durability assessment, information is gathered
on (1) the severity of in-service loading and/or
customer usage, (2) the stress concentrations
produced by the geometry of critical load- carrying
elements, and (3) the material
properties appropriate for design strength
calculations.
Based on this information, the most likely potential
failure modes for the product or structure are
identified, which determines the appropriate stress
analysis and damage models required for the
assessment.
A typical durability assessment might consider a
wide range of critical failure modes capable of
rendering the product useless, such as excessive
deflection, buckling, warping, yielding, brinnelling,
spalling, galling, cracking, rupture, and so on.
These failure modes can be evaluated using the
appropriate analysis for deformation, creep,
fatigue, fracture, corrosion, rupture, etc.
Once the durability assessment has identified the
critical failure modes, it is often a simple matter
to design against them and improve the durability of
your product or structure. To validate your design
changes, a meaningful bench test can be developed
that is based on the load cases associated with
these critical failure modes.
Some project examples.
Validating Durability:
Road grader components — Evaluating durability
based on expected customer usage
Extending Warranty:
Office furniture — Durability testing of a new
component design
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