Destructive
testing
In destructive
testing (or destructive physical analysis, DPA)
tests are carried out to the specimen's failure, in order to understand a
specimen's performance or material behavior under different loads. These tests
are generally much easier to carry out, yield more information, and are easier
to interpret than nondestructive testing. Destructive testing is most
suitable, and economic, for objects which will be mass-produced, as the
cost of destroying a small number of specimens is negligible. It is usually not
economical to do destructive testing where only one or very few items are to be
produced (for example, in the case of a building). Analyzing and documenting
the destructive failure mode is often accomplished using a high-speed camera recording
continuously (movie-loop) until the failure is detected. Detecting the failure
can be accomplished using a sound detector or stress gauge which produces a
signal to trigger the high-speed camera. These high-speed cameras have advanced
recording modes to capture almost any type of destructive failure. After
the failure the high-speed camera will stop recording. The captured images can
be played back in slow motion showing precisely what happens before,
during and after the destructive event, image by image.
Contents
- 1Methods and techniques
- 1.1Testing of large structures
- 1.2Software testing
- 2Automotive testing
- 3Aircraft testing
- 4See also
Methods and
techniques
Testing of
large structures
Snapshot
from shake-table video of a 6-story non-ductile concrete building
Building
structures or large nonbuilding structures (such as dams and
bridges) are rarely subjected to destructive testing due to the prohibitive
cost of constructing a building, or a scale model of a building, just to
destroy it.
Earthquake
engineering requires a good understanding of how structures will perform
at earthquakes. Destructive tests are more frequently carried out for
structures which are to be constructed in earthquake zones. Such tests are
sometimes referred to as crash tests, and they are carried out to
verify the designed seismic performance of a new building, or the
actual performance of an existing building. The tests are, mostly, carried out
on a platform called a shake-table which is designed to shake in the
same manner as an earthquake. Results of those tests often include the
corresponding shake-table videos.
Testing of
structures in earthquakes is increasingly done by modelling the structure using
specialist finite element software.
Software
testing
Destructive
software testing is a type of software testing which attempts to
cause a piece of software to fail in an uncontrolled manner, in order to test
its robustness and to help establish range limits, within which the SW will operate
in a stable and reliable manner.
Automotive
testing
Oblique
frontal crash test of a Dodge Dart.
Automobiles are
subject to crash testing by both automobile manufactures and a
variety of agencies.
Aircraft testing
Further
information: Aviation safety
NASA air safety
experiment Controlled Impact Demonstration. The airplane is a Boeing
720 testing a form of jet fuel, known as "antimisting kerosene",
which formed a difficult-to-ignite gel when agitated violently, as in a crash.
There has also
been extensive destructive testing of passenger and military aircraft,
conducted by aircraft manufacturers and organizations like NASA.
The 2012 Boeing 727 crash experiment was conducted and filmed by
the Discovery channel.
See also
- Crash test
- Hardness tests
- Median lethal dose
- Metallographic test
- Nondestructive testing
- Reproducibility
- Show and Display
- Stress tests
- Testability
