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Evaluation of the EC8-3 confidence factors for the characterization of concrete strength in existing structures

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An Erratum to this article was published on 28 August 2012

Abstract

A probabilistic framework is defined to evaluate the values of the Confidence Factors (CFs) proposed in Eurocode 8 Part 3 (EC8-3) for the characterization of material properties. This evaluation is presented for the concrete compressive strength but its validity for other material properties can also be inferred from the results obtained. The number of material tests and the existence of prior knowledge are the essential aspects for the CF quantification. The probabilistic framework proposed in the first part of the study does not consider the existence of prior knowledge and is based on the concept of confidence intervals. In the second part of the study, the effects of prior knowledge are considered using a Bayesian framework. The combination of testing data obtained from different types of tests is also addressed as an extension of the referred Bayesian approach. Results indicate that the EC8-3 proposed CFs for KL1 and KL2 are adequate, but for KL3 it is suggested that a larger value should be used.

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Acknowledgments

The financial support of the Portuguese Foundation for Science and Technology to the research project “Development and calibration of the Eurocode 8-Part 3 seismic safety assessment methodologies for existing buildings” (PTDC/ECM/108098/2008) is gratefully acknowledged.

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Authors and Affiliations

  1. Civil Engineering Department, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal

    Xavier Romão, Rui Gonçalves & Raimundo Delgado

  2. Civil Engineering Department, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193, Aveiro, Portugal

    Aníbal Costa

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  1. Xavier Romão
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  2. Rui Gonçalves
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  3. Aníbal Costa
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  4. Raimundo Delgado
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Correspondence to Xavier Romão.

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Romão, X., Gonçalves, R., Costa, A. et al. Evaluation of the EC8-3 confidence factors for the characterization of concrete strength in existing structures. Mater Struct 45, 1737–1758 (2012). https://doi.org/10.1617/s11527-012-9868-4

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  • DOI: https://doi.org/10.1617/s11527-012-9868-4

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