A structural health monitoring system based on optical sensors has been developed and installed on the indoor soccer arena "Zarya" in Novosibirsk. The system integrates 119 fiber optic sensors: 85 strain, 32 temperature and 2 displacement sensors. In addition, total station is used for measuring displacement in 45 control points. All of the constituents of the supporting structure are subjects for monitoring: long-span frames with under floor ties, connections, purlins and foundation.

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Inscription of structures by a femtosecond laser beam allows one to produce disordered structures capable of increasing the Rayleigh backscatter intensity in the fibre at relatively low induced losses, which makes them potential candidates for use as reflectors in fibre lasers. Here we report a narrow-band erbium fibre laser with random distributed feedback produced by femtosecond laser writing in half-open cavity and ring cavity configurations. In the half-open cavity configuration, single-frequency lasing is observed at output powers up to 2.8 W, with a linewidth near 10 kHz. In the ring cavity configuration, single-frequency operation is observed over the entire range of output powers studied. At the highest output power, 7 mW, the linewidth does not exceed 0.7 kHz.

Interference imaging techniques are widely used for studying surface and internal structure of various objects. By varying the operating wavelength of the interference system, one can also obtain the information about the spectral properties of the inspected specimen. For multi-spectral interference imaging applications, wide-band high power light sources are necessary. Most of the existing sources suffer from speckle noise, low brightness or high price. In this paper, we demonstrate the applicability of a laser-induced plasma light source for interference imaging and quantitative phase measurements. Narrow-band spectral filtration of its illumination within a wavelength range 240-2600 nm allows to design cost-effective schemes for a variety of metrological applications including digital holography and spectral-domain optical coherence tomography.