Picture of sea vessel plough through rough maritime conditions

Innovations in marine technology, pioneered through Open Access research...

Strathprints makes available scholarly Open Access content by researchers in the Department of Naval Architecture, Ocean & Marine Engineering based within the Faculty of Engineering.

Research here explores the potential of marine renewables, such as offshore wind, current and wave energy devices to promote the delivery of diverse energy sources. Expertise in offshore hydrodynamics in offshore structures also informs innovations within the oil and gas industries. But as a world-leading centre of marine technology, the Department is recognised as the leading authority in all areas related to maritime safety, such as resilience engineering, collision avoidance and risk-based ship design. Techniques to support sustainability vessel life cycle management is a key research focus.

Explore the Open Access research of the Department of Naval Architecture, Ocean & Marine Engineering. Or explore all of Strathclyde's Open Access research...

Hybrid optical-fibre/geopolymer sensors for structural health monitoring of concrete structures

Perry, M and Saafi, M and Fusiek, G and Niewczas, P (2015) Hybrid optical-fibre/geopolymer sensors for structural health monitoring of concrete structures. Smart Materials and Structures, 24 (4). ISSN 0964-1726

[img]
Preview
Text (hybrid_geo)
hybrid_geo.pdf
Accepted Author Manuscript

Download (9MB) | Preview
[img]
Preview
Text (Perry-etal-SMS-2015-Hybrid-optical-fibre-geopolymer-sensors-for-structural-health)
Perry_etal_SMS_2015_Hybrid_optical_fibre_geopolymer_sensors_for_structural_health.pdf
Accepted Author Manuscript

Download (9MB) | Preview

Abstract

In this work, we demonstrate hybrid optical-fibre/geopolymer sensors for monitoring temperature, uniaxial strain and biaxial strain in concrete structures. The hybrid sensors detect these measurands via changes in geopolymer electrical impedance, and via optical wavelength measurements of embedded fibre Bragg gratings. Electrical and optical measurements were both facilitated by metal-coated optical fibres, which provided the hybrid sensors with a single, shared physical path for both voltage and wavelength signals. The embedded fibre sensors revealed that geopolymer specimens undergo 2.7 mepsilon of shrinkage after one week of curing at 42 °C. After curing, an axial 2 mepsilon compression of the uniaxial hybrid sensor led to impedance and wavelength shifts of 7 × 10−2 and −2 × 10−4 respectively. The typical strain resolution in the uniaxial sensor was 100 $\mu \varepsilon $. The biaxial sensor was applied to the side of a concrete cylinder, which was then placed under 0.6 mepsilon of axial, compressive strain. Fractional shifts in impedance and wavelength, used to monitor axial and circumferential strain, were 3 × 10−2 and 4 × 10−5 respectively. The biaxial sensor's strain resolution was approximately 10 $\mu \varepsilon $ in both directions. Due to several design flaws, the uniaxial hybrid sensor was unable to accurately measure ambient temperature changes. The biaxial sensor, however, successfully monitored local temperature changes with 0.5 °C resolution.