Variability of small scale model reinforced concrete and implications for geotechnical centrifuge testing

Jonathan Knappett, Michael Brown, Lauren Shields, Asad H. Al-Defae, Marianna Loli

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

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Abstract

There are soil-structure interaction problems for which it is important to model both the relative soil-structure stiffness and strength. Examples from the earthquake engineering field include the design of resilient rocking-isolated foundations and the seismic stabilisation of slopes using piling. In both cases the aim is to ensure a preferred failure mode happens first in the soil instead of the structure i.e. controlled bearing failure of the foundation or soil yielding around piles. A recently developed model reinforced concrete for centrifuge testing can simulate stiffness and strength simultaneously, but suffers from variability in the material properties, as does the full-scale material. This paper presents a series of element tests on the variability of model reinforced concrete elements representative of large square monolithic bridge piers and slender square piles. Coefficients of variation for various material and element properties have been determined and shown to be similar to typical values for full-scale reinforced concrete elements obtained from the literature. It is also demonstrated that curing time beyond 28 days does not substantially affect strength and variability and that models of different absolute volume can be produced without inducing detrimental size effects. The results are used to discuss the selection of mean design strengths for model structural elements in centrifuge experiments using a quantitative statistical approach where there are competing structural and soil failure modes.
Original languageEnglish
Title of host publicationPhysical Modelling in Geotechnics
Subtitle of host publicationProceedings of the 9th International Conference on Physical Modelling in Geotechnics (ICPMG 2018), July 17-20, 2018, London, United Kingdom
EditorsAndrew McNamara, Sam Divall, Richard Goodey, Neil Taylor, Sarah Stallebrass, Jignasha Panchal
PublisherCRC Press-Taylor & Francis Group
Pages241-246
Edition1
ISBN (Print)9781138559752
DOIs
Publication statusPublished - 24 Oct 2018
Event9th Int. Conf. on Physical Modelling in Geotechnics 2018 - City University, London, United Kingdom
Duration: 17 Jul 201820 Jul 2018

Conference

Conference9th Int. Conf. on Physical Modelling in Geotechnics 2018
Abbreviated titleICPMG2018
CountryUnited Kingdom
CityLondon
Period17/07/1820/07/18

Fingerprint

Centrifuges
Reinforced concrete
Testing
Piles
Soils
Failure modes
Bearings (structural)
Stiffness
Bridge piers
Soil structure interactions
Curing
Materials properties
Stabilization
Experiments

Keywords

  • model concrete
  • geotechnical centrifuge
  • Scaling

Cite this

Knappett, J., Brown, M., Shields, L., Al-Defae, A. H., & Loli, M. (2018). Variability of small scale model reinforced concrete and implications for geotechnical centrifuge testing. In A. McNamara, S. Divall, R. Goodey, N. Taylor, S. Stallebrass, & J. Panchal (Eds.), Physical Modelling in Geotechnics: Proceedings of the 9th International Conference on Physical Modelling in Geotechnics (ICPMG 2018), July 17-20, 2018, London, United Kingdom (1 ed., pp. 241-246). CRC Press-Taylor & Francis Group. https://doi.org/10.1201/9780429438646
Knappett, Jonathan ; Brown, Michael ; Shields, Lauren ; Al-Defae, Asad H. ; Loli, Marianna. / Variability of small scale model reinforced concrete and implications for geotechnical centrifuge testing. Physical Modelling in Geotechnics: Proceedings of the 9th International Conference on Physical Modelling in Geotechnics (ICPMG 2018), July 17-20, 2018, London, United Kingdom. editor / Andrew McNamara ; Sam Divall ; Richard Goodey ; Neil Taylor ; Sarah Stallebrass ; Jignasha Panchal. 1. ed. CRC Press-Taylor & Francis Group, 2018. pp. 241-246
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Knappett, J, Brown, M, Shields, L, Al-Defae, AH & Loli, M 2018, Variability of small scale model reinforced concrete and implications for geotechnical centrifuge testing. in A McNamara, S Divall, R Goodey, N Taylor, S Stallebrass & J Panchal (eds), Physical Modelling in Geotechnics: Proceedings of the 9th International Conference on Physical Modelling in Geotechnics (ICPMG 2018), July 17-20, 2018, London, United Kingdom. 1 edn, CRC Press-Taylor & Francis Group, pp. 241-246, 9th Int. Conf. on Physical Modelling in Geotechnics 2018 , London, United Kingdom, 17/07/18. https://doi.org/10.1201/9780429438646

Variability of small scale model reinforced concrete and implications for geotechnical centrifuge testing. / Knappett, Jonathan; Brown, Michael; Shields, Lauren; Al-Defae, Asad H.; Loli, Marianna.

Physical Modelling in Geotechnics: Proceedings of the 9th International Conference on Physical Modelling in Geotechnics (ICPMG 2018), July 17-20, 2018, London, United Kingdom. ed. / Andrew McNamara; Sam Divall; Richard Goodey; Neil Taylor; Sarah Stallebrass; Jignasha Panchal. 1. ed. CRC Press-Taylor & Francis Group, 2018. p. 241-246.

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

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Knappett J, Brown M, Shields L, Al-Defae AH, Loli M. Variability of small scale model reinforced concrete and implications for geotechnical centrifuge testing. In McNamara A, Divall S, Goodey R, Taylor N, Stallebrass S, Panchal J, editors, Physical Modelling in Geotechnics: Proceedings of the 9th International Conference on Physical Modelling in Geotechnics (ICPMG 2018), July 17-20, 2018, London, United Kingdom. 1 ed. CRC Press-Taylor & Francis Group. 2018. p. 241-246 https://doi.org/10.1201/9780429438646