Abstract:
Extensometers are mechanical devices used to measure changes in length or
strain in materials under stress or deformation. They provide valuable data for
evaluating material properties, structural integrity, and mechanical behavior. One
specific type of extensometer is the bolt-on extensometer, which is easily mounted
onto the surface of a specimen using bolts or clamps.
This thesis project aims to investigate and analyze the role of extensometers
and bolt-on extensometers in measuring strain and deformation in materials, focusing
on their advantages and potential failure modes. Extensometers are widely used
mechanical devices in engineering, material testing, and research to assess material
properties and structural behavior. Bolt-on extensometers, a specific type of
extensometer, offer the advantage of easy installation without damaging the specimen.
The study begins with an in-depth literature review to understand the
theoretical background, working principles, and applications of extensometers and
bolt-on extensometers. The advantages of extensometers lie in their ability to provide
accurate and reliable measurements of strain. They aid in the design, optimization, and
safety assessment of structures.
The thesis project also investigates the specific advantages of bolt-on
extensometers, which include non-destructive testing capabilities and versatility in
measuring strain in delicate or composite materials. The easy installation and removal
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of bolt-on extensometers make them suitable for various testing scenarios, both in
laboratory settings and in the field.
However, the research also delves into the potential failure modes of bolt-on
extensometers. Mechanical issues such as arm or jaw failures, contact point
discrepancies, or central body malfunctions can lead to inaccurate or inconsistent
measurements. Calibration problems and environmental factors, such as extreme
temperatures or corrosive substances, can also affect the performance of these devices
