Kearsley, Elsabe P.Jacobsz, Schalk Willem2019-10-082019-10-082018Kearsley, P. & Jacobsz, S.W. 2018, 'Condition assessment of reinforced concrete beams – comparing digital image analysis with optic fibre Bragg gratings', MATEC Web of Conferences, vol. 199, no. 6011, pp. 1-7.2261-236X (online)10.1051/matecconf/201819906011http://hdl.handle.net/2263/71608Reinforced concrete is the most widely used construction material and thus effective condition assessment of reinforced concrete elements forms a significant part of structural health monitoring. An effective structural health monitoring system should be able to give the owner prior warning that structural elements are reaching conditions approaching either serviceability or ultimate limit states. The aim of this investigation is to compare strain data recorded during load testing of a reinforced concrete beam using Fibre optic Bragg Gratings (FBG) and a photographic technique to determine circumstances most suitable for the use of each of the techniques. The test results indicate that FBG sensors can be used to detect small strains as well as large strains in uncracked concrete elements, while optical images can be used to accurately map crack development over the surface area of the structure.en© The Authors, published by EDP Sciences. This is an open access article distributed under the terms of the Creative Commons Attribution License 4.0.Reinforced concreteOwnerUncracked concreteFibre optic Bragg gratings (FBG)Concrete beams and girdersConcrete testingGeometrical opticsLoad testingRepairRetrofittingStrainStructural health monitoringCondition assessmentsDigital image analysisPhotographic techniquesUltimate limit stateEngineering, built environment and information technology articles SDG-09SDG-09: Industry, innovation and infrastructureArticle