Quantification of subsurface defects in reinforced concrete of bridges by unsupervised segmentation of IR images

Research output: Chapter in Book/Report/Conference proceedingConference contribution

9 Downloads (Pure)


This paper presents segmentation analysis of Infrared (IR images of reinforced concrete (RC blocks for characterisation and quantification of corrosion defects using unsupervised clustering. The IR images used in this study were collected during cool down process of RC slabs to laboratory environment temperature through convection heat exchange. The RC slabs were cast from a normal strength mix, typical for bridge construction in the UK and Ireland. The slabs had two steel rebars with protruding ends that were used for accelerated corrosion setups. Unsupervised clustering was conducted on IR images by applying k-means clustering method on normalised temperature readings in a region of interest. In this paper, the performance of clustering method to distinguish between environmental or surface effects and true bridge anomalies is studied, and the corrosion-affected concrete is quantified. Variation of thermal contrast and quantity of defective concrete during the experiments as well as discussion of the results in context provides a basis for improved implementation of IRT for RC structures and contributes to wider objectives of structural health monitoring (SHM.

Original languageEnglish
Title of host publicationProceedings of the IABSE Symposium Istanbul 2023: Long Span Bridges
Place of PublicationIstanbul
PublisherInternational Association for Bridge and Structural Engineering (IABSE)
Number of pages11
ISBN (Electronic)9783857481918
Publication statusPublished - 2023
EventIABSE Symposium 2023- Istanbul-Turkey: Long Span Bridges - HYATT REGENCY ISTANBUL ATAKOY HOTEL/ISTANBUL, Istanbul, Turkey
Duration: 26 Apr 202328 Apr 2023

Publication series

NameIABSE Reports
Publisher International Association of Bridge and Structural Engineering


ConferenceIABSE Symposium 2023- Istanbul-Turkey


  • Infrared Thermography (IRT)
  • Rebar corrosion
  • Reinforced Concrete (RC
  • Structural Health Monitoring (SHM)
  • Unsupervised clustering

ASJC Scopus subject areas

  • Civil and Structural Engineering
  • Building and Construction


Dive into the research topics of 'Quantification of subsurface defects in reinforced concrete of bridges by unsupervised segmentation of IR images'. Together they form a unique fingerprint.

Cite this