Strain Gauge Testing (NDT) 

STStrain Gauge Testing (NDT) – is a condition monitoring method for measuring the deformation of a component. Strain gauges can be fixed onto the surface of a component in service or embedded in the component during manufacture. Strain is the relative change in shape or size of a material subject to a stress. ST measures this change and analysis of ST data allows for the identification of the actual structural stresses, the recording and quantification of load cycles and the determination of impact events. These in turn feed into fatigue life assessments, design changes and maintenance planning.

ST is applied to a wide range of components, such as bridges, tunnels, railcars, vessels, wind turbine blades and concrete structures. Strain gauges and strain measurement have been widely used in structural health monitoring (SHM – see ‘What the Hec?!’, October 2010) systems as a means of detecting and localising damage.

For more information on ST applied to the condition monitoring of wind turbine blades see:

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