Application of strut-and-tie models for assessing RC half-joints not complying with current code specifications
Keywords:half joints, reinforced concrete, structural assessment, strut-and-tie models
The work described is concerned with an investigation of the effectiveness of the use of strut-and-tie models for the structural assessment of half joints. Such elements form a part of many existing bridges which, although not complying with current code specifications, have not as yet displayed any significant signs of distress in spite of the increase in traffic volume and loads over the years. The work is based on a comparative study of the predicted and experimentally established values of load-carrying capacity and location and causes of failure of half-jointed beams with reinforcement layouts that replicate those found in structures designed in accordance with previous code specifications. The results obtained show significant shortcomings of the assessment method as this is found not only to underestimate load-carrying capacity by a margin ranging between 40 % and 65 %, but also to often fail to identify the location and causes of failure. Therefore, there is a need for an alternative assessment method that will be based on concepts capable of both providing a realistic description of structural-concrete behaviour and identifying the causes of failure leading to the loss of load-carrying capacity.
J. Schlaich, K. Schafer, M. Jennewein. Toward a consistent design of structural concrete. PCI Journal 32(3):74–150, 1987. https://doi.org/10.15554/pcij.05011987.74.150.
The European Committee for Standardization. Eurocode 2: Design of concrete structures. Part 1-1: General rules and rules for buildings. (Standard No. EN 1992-1), 2004.
The European Committee for Standardization. Eurocode 8: Design of structures for earthquake resistance. Part 1-1: General rules, seismic standards and rules for buildings. (Standard No. EN 1998-1), 2004.
Transport Scontland (Agency of the Scottish Executive). TS interim amendment N◦20 – Concrete half-joint deck structures, 2006. [2022-10-15], https://www.transport.gov.scot/media/6084/ts_ia_20.pdf.
P. Desnerck, J. M. Lees, C. T. Morley. Impact of the reinforcement layout on the load capacity of reinforced concrete half-joints. Engineering Structures 127:227–239, 2016. https://doi.org/10.1016/j.engstruct.2016.08.061.
FIB Task Group 4.4. FIB bulletin 45 – Practitioners’ guide to finite element modelling of reinforced concrete structures, 2011. International Federation for Structural Concrete.
P. Desnerck, J. M. Lees, C. T. Morley. Strut-and-tie models for deteriorated reinforced concrete half-joints. Engineering Structures 161:41–54, 2018. https://doi.org/10.1016/j.engstruct.2018.01.013.
M. D. Kotsovos. Compressive Force-Path Method: Unified Ultimate Limit-State Design of Concrete Structures. Springer, London, 2014.
M. D. Kotsovos. Conflicts between reinforced concrete design assumptions and actual concrete behaviour. Proceedings of the Institution of Civil Engineers – Structures and Buildings 175(1):34–45, 2022. https://doi.org/10.1680/jstbu.19.00003.
M. D. Kotsovos. Beam theory – A proposed alternative basis for RC design. Proceedings of the Institution of Civil Engineers – Structures and Buildings 2021. [Ahead of print], https://doi.org/10.1680/jstbu.20.00064.
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Copyright (c) 2022 Gregoria Kotsovou, Emmanouil Vougioukas, Demetrios M. Cotsovos
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