Print Email Facebook Twitter Identification of Stop Criteria for Large-Scale Laboratory Slab Tests Using Digital Image Correlation and Acoustic Emission Title Identification of Stop Criteria for Large-Scale Laboratory Slab Tests Using Digital Image Correlation and Acoustic Emission Author Christensen, Christian Overgaard (Technical University of Denmark) Zhang, F. (TU Delft Concrete Structures) Zarate Garnica, G.I. (TU Delft Concrete Structures) Lantsoght, E.O.L. (TU Delft Concrete Structures; Universidad San Francisco de Quito) Goltermann, Per (Technical University of Denmark) Schmidt, Jacob Wittrup (Aalborg University) Date 2022 Abstract Advanced monitoring methods are required to identify stop criteria in proof-load tests. In this study, the combined methodology of two-dimensional digital image correlation and acoustic emission is investigated for its applicability for future implementation in field tests. The two monitoring systems are deemed to provide valuable insight with external measurements from digital image correlation and internal measurements from acoustic emission. Two overturned T-section reinforced concrete slabs (0.37 × 1.7 × 8.4 m) tested under laboratory conditions are used for the assessment. The first slab test served as a preliminary test to enable sensor placement and creation of a relevant loading protocol. The main scientific results lead to a proposal for a test procedure using the combined methodology based on results, observations, and experiences from an individual stop criteria assessment for the two methods. The results include full-field plots, an investigation of the time of crack detection and monitoring of crack widths with digital image correlation, and a qualitative assessment of activity vs. load followed by a quantitative evaluation of calm ratios using acoustic emission. The individual results show that both digital image correlation and acoustic emission can identify damage occurrence earlier than other secondary methods. At crack detection (415 kN), crack widths were measured at widths between 0.078 mm to 0.125 mm and can be monitored until reaching the stop criterion at 463 kN (Eurocode SLS threshold of wmax = 0.2 mm). The acoustic emission results were limited by the pre-defined loading protocol and thus, only indicated that damage occurred sometime between 300 kN and 500 kN (pre-defined load levels). Therefore, the proposal for test procedure involves a methodology, where the loading protocol may be updated during testing based on monitoring results and thus provide even more valuable data. Subject Acoustic emissionConcrete slab bridgesCrack evaluationDigital image correlationLoad cyclesLoad historyProof-loadingRepeated loadingStop criteria To reference this document use: http://resolver.tudelft.nl/uuid:b4d4f912-1b9c-4cdd-9175-0a3cf1e3a950 DOI https://doi.org/10.3390/infrastructures7030036 ISSN 2412-3811 Source Infrastructures, 7 (3) Part of collection Institutional Repository Document type journal article Rights © 2022 Christian Overgaard Christensen, F. Zhang, G.I. Zarate Garnica, E.O.L. Lantsoght, Per Goltermann, Jacob Wittrup Schmidt Files PDF infrastructures_07_00036_v2.pdf 4.67 MB Close viewer /islandora/object/uuid:b4d4f912-1b9c-4cdd-9175-0a3cf1e3a950/datastream/OBJ/view