Durability of Concrete under Combined Impact Environment and Mechanical Load: Analysis of Experimental Studies

Today, there are several methods for predicting the durability of reinforced concrete structures. In most cases, one of the dominant destruction processes is taken into account – either carbonization or chloride penetration. Experimental results and field observations show that this is an unrealistic approach. Therefore, it is necessary to develop a method for determining the durability of concrete under combined impacts, i. e. with the penetration of chlorides into it and mechanical load. The paper describes in detail an experimental method for studying the effect of mechanical load on the penetration of chlorides into the pore space of cement-based materials. A test method is presented that makes it possible to determine realistic diffusion coefficients of chloride ions in concrete under compressive or tensile stress. As a result of the experiments carried out, it has been determined that the combination of mechanical loads and environmental influences can be much more significant than just environmental influence without the influence of mechanical loading. In fact, the service life of reinforced concrete structures depends on many possible combinations of mechanical loads and environmental influences, including freeze-thaw cycles. Thus, cracks formed during freeze-thaw cycling should be taken into account in tests of combined environmental and mechanical stress in order to better understand and systematically describe the effect of such exposure on the durability of concrete. For reliable prediction of the service life of reinforced concrete structures, it is also necessary to take into account the influence of the applied cyclic stress.

1. EN 1992-1-1 Eurocode 2: Design of Concrete Structures - Part 1-1: General Rules and Rules for Buildings. European Commitiee for Standardization, 2004. Available at: https://www.phd.eng.br/wp-content/uploads/2015/12/en.1992.1.1.2004.pdf.

2. ACI 318-14 Building Code Requirements for Structural Concrete and Commentary. American Concrete Institute, 2014. Available at: http://aghababaie.usc.ac.ir/files/150650 5203365.pdf.

3. Standard Specifications for Concrete Structures - 2007 “Design”. JSCE Guidelines for Concrete No 15. Japan Society of Civil Engineers, 2007. Available at: https://www.jsce-int.org/system/files/JGC15_Standard_Specifications_Design_1.0.pdf.

4. GB 50010-2002 Code for Design of Concrete Structures. China Building Science Acedemy, 2010.

5. Schießl P., Bamforth P., Baroghel-Bouny V., Corley G. W., Faber M. H., Forbes J. M., Gehlen C., Helene P., Helland S., Ishida T., Markeset G., Nilsson L. O., Rostam S., Siemes A., Walraven J. C. (2006). Model Code for Service Life Design. Fib Bulletin No 34. International Federation for Structural Concrete. 116.

6. 2013 Report Card for America’s Infrastructure. ASCE. Available at: https://www.api.org/~/media/energyinfrastructure/images/rail/related-documents/report-card-for-americas-infrastructure.pdf.

7. Wittmann F. H., Zhao T., Jiang F., Wan X. (2012) Influence of Combined Actions on Durability and Service Life of Reinforced Concrete Structures Exposed to Aggressive Environment. Restoration of Buildings and Monuments, (18), 105-112. https://doi.org/10.1515/rbm-2012-6510.

8. Wan X., Wittmann F. H., Zhao T. (2011) Influence of Mechanical Load on Service Life of Reinforced Concrete Structures under Dominant Influence of Carbonation. Restoration of Buildings and Monuments, (17), 103-110. https://doi.org/10.1515/rbm-2011-6437.

9. Yao Y., Wang L., Wittmann F. H. (2013) Report rep043: Publications on Durability of Reinforced Concrete Structures under Combined Mechanical Loads and Environmental Actions: An Annotated Bibliography. RILEM. Available at: https://www.rilem.net/publication/publication/427.

10. Measurement of Time-Dependent Strains of Concrete. Ma-terials and Structures: RILEM TC 107-CSP. Materials and Structures. 1998, 31, 507-512.

11. Yao Y., Wang L., Wittmann F. H., Schlangen E., Gehlen C., Wang Z., Alava H. E., Cao Y., Yunus B., Li J. (2017) Recommendation of RILEM TC 246-TDC: Test Methods to Deter-Mine Durability of Concrete under Combined Environmental Actions and Mechanical Load. Materials and Structures, 50, 155. https://doi.org/10.1617/s11527-017-1000-3.

12. SEN EN 14629 Products and Systems for the Protection and Repair of Concrete Structures - Test Methods - Determination of Chloride Content in Hardened Concrete. European Committee for Standardization (CEN), 2007. 14.

13. EN 12390-11 Testing Hardened Concrete - Part 11: Determination of the Chloride Resistance of Concrete, Unidirectional Diffusion. Dansk Standardiseringsrad (DS), 2015. 35.

14. Bartholomew M., Edvardsen C., Ferreira M., von GreveDierfeld S., Gulikers J., Helland S., Markeset G., McKenna P., Papworth F., Pielstick B., Rahimi A. (2015) Benchmarking of Deemed-to-Satisfy Provisions in Standards: Durability of Reinforced Concrete Structures Exposed to Chlorides. Fib Bulletin No 76. International Federation for Structural Concrete. 191. https://doi.org/10.35789/fib.BULL.0076.

15. Setzer M. J., Fagerlund G., Janssen D. J. (1996) CDF Test - Test Method for the Freeze Thaw and Deicing Resistance of Concrete - Tests with Sodium Chloride (CDF). RILEM TC 117-FDC. Materials and Structures, 29, 523-528.

16. ISO 5725-1. 1994 Accuracy (Trueness and Precision) of Measurement Methods and Results. International Organization for Standardization (ISO), 1998. 28.

17. Setzer M. J., Auberg R., Keck H.-J. (2002) Development of the Micro-Ice-Lens Model. International RILEM Workshop on Frost Resistance of Concrete. RILEM Publications SARL, 133-145.

18. Leonovich S. N., Al'-Fakikh O. A. M. (2004) Residual Frost Resistance of concrete of Operated Structures Vestnik Brestskogo Gosudarstvennogo Tekhnicheskogo Universiteta. Seriya: Stroitel'stvo i Arkhitektura = Bulletin of the Brest State Technical University. Series: Construction and Architecture, (1), 125-128 (in Russian).

19. Leonovich S. N. (2009) Evaluation of the Residual Frost Resistance of Concrete of Operated Structures by the Method of Separation with Chipping. Izvestiya Vysshikh Uchebnykh Zavedeniy. Stroitel’stvo = News of Higher Education Institutions. Construction, (6), 75-82 (in Russian).

20. Leonovich S. N., Piradov K. A. (2009) Evaluation of Frost Resistance by Methods of Fracture Mechanics. Vestnik Grazhdanskikh Inzhenerov = Bulletin of Civil Engineers, (3), 134-136 (in Russian).