Combined contribution of experiments and modeling to better understand mechanical properties of concrete

Combined contribution of experiments and modeling to better understand mechanical properties of concrete

Taoufik Achour Saloua El Euch Khay Emna Jarraya Jamel Neji 

Laboratoire de génie civil, École nationale d’ingénieurs de Tunis, université de Tunis El Manar, BP 37, Le Belvédère, 1002 Tunis, Tunisie

Laboratoire de matériaux d’optimisation et d’énergie pour la durabilité, École nationale d’ingénieurs de Tunis, université de Tunis El Manar, BP 37, Le Belvédère, 1002 Tunis, Tunisie

Corresponding Author Email: 
achour_taoufik@yahoo.fr; eleuchsaloua@yahoo.fr; e.emna.jarraya@gmail.com; jamel.neji@enit.rnu.tn
Page: 
123-136
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DOI: 
https://doi.org/10.3166/rcma.2017.00008
Received: 
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Accepted: 
| | Citation

ACCESS

Abstract: 

The work presented in this paper is interested in the theoretical modelling of the mechanical properties of concretes through their experimental characterization. It is to validate the relevance of the latest prediction models of the compressive and tensile strengths of concrete when applied to concrete mixtures made with local limestone aggregates and using filler sand. For that purpose, a variety of optimized concrete mixtures (sand concrete, micro-concrete, and concrete), recently made in 2016 at National Engineering School of Tunis, with aggregates from the same source, was tested experimentally at different curing ages. The results of the experimental tests are within the performance range of ordinary concrete. For the compressive strength, the tested models Béton-LabPro3, Tango, and ACI318 proved all to be relevant at different degrees, but within the range of the studied performance. However, the Tango and ACI models do not take into account in a significant manner the effect of aggregates on the compressive strength of concrete. With regard to the tensile strength, the BAEL and Eurocode models were found to underestimate this property, while the ACI and Oluokun models were found to overestimate it. In fact, the average difference between models’ predicted values and those measured was found to be high. This high difference is mainly due to the fact that these models do not take into account the topology and the nature of the aggregates. On the other hand, the Béton-LabPro3 and Achour et al. models well-estimated the tested mixtures tensile strength as the difference between the predicted and experimental values was low. This finding reflects the merits of these two models, especially the one by Achour et al., which explicitly consider the cohesion in the transition zone between the cement paste and aggregates as well as the aggregates traction resistance limit.

Keywords: 

concrete, theoretical modeling, aggregate, fillers, compressive strength, tensile strength

1. Introduction
2. Présentation des modèles
3. Campagne expérimentale
4. Modélisations
5. Conclusion
  References

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