Bragg grating-based multiaxial strain sensing: its application to residual strain measurement in composite laminates

摘要

The single peak of the spectrum of a fibre Bragg grating written in a standard low birefringence optical fibre splits in two peaks when a transverse strain field is applied due to the promotion of a strain induced birefringence. In a composite laminate, the theory predicts a plane stress state, which allows using a single embedded Bragg grating to obtain simultaneously both components of the strain field.