Porous/Plain concrete interface fracture characterization towards optimization

LAMES is the Laboratory for Modelling, Experimentation and Survey of transport infrastructures. https://lames.univ-gustave-eiffel.fr/en/

It is located in the site of the University Gustave Eiffel, in Nantes. Its areas of research concern mechanical behavior, modelling, survey and management of transport infrastructures (roads, railways, airfield pavements, industrial platforms).

On may 1st 2024, the personnel of LAMES consists of 23 permanent members (including 14 researchers and engineers, 8 technicians, 1 administrative) and 12 non permanent members (including 8 PhD students).

Urban Heat Island (UHI) has increased city temperatures by more than 6°C compared to that of rural areas (https://www.jpl.nasa.gov/news/nasas-ecostress-maps-european-heat-wave-from-space). To mitigate this rise in urban temperatures, UHI-Reducing (UHI-R) pavements have been developed. UHI-R pavement types include permeable pavements that reduce the surface temperatures by enhancing the evaporation process (Tormos et al. 2025). Porous Removable Urban Pavements (RUP), that are characterized by their high permeability (Sedran et al. 2023), can be utilized to reduce UHI. Porous RUP are bi-layer systems consisting of a highly porous surface layer having a porosity of 25%, placed over plain concrete.

While the interface bonding condition of multi-layers pavements is critical for their durability (Petit et al. 2018), a lack of studies on their interface fracture has been identified. Prior to this internship, interface fracture characterization of the Porous/Plain concrete is initiated. The Wedge Splitting Test (WST) (Tschegg 1986, Gharbi et al. 2017), combined with Digital Image Correlation (DIC), is used to characterize the Mode I interface fracture properties as a part of ongoing PhD research (Tormos 2022-26).

Building on this WST work, and with the aid of DIC analysis, the aim of this internship is to characterize the interface fracture of the Porous/Plain concrete specimens. The internship consists of:

1- Conduct post processing of the WSTs to extract interface fracture properties

2- Undertake critical comparison of effects of different specimen preparation techniques and curing conditions on the interface fracture properties

The final goal of this internship is to propose a fundamental interface characterization method, to extract the interface fracture parameters needed for pavement scale simulations and to quantify the effects of the construction methods and curing conditions on the interface bonding performance.

References

Gharbi, M., Nguyen, M.L., Trichet, S., Chabot, A. Characterisation of the bond between asphalt layers and glass fiber grid with help of a Wedge Splitting Test. In: Loizos, A., Al-Qadi, I., Scarpas, T. (eds) BCRRA, CRC Press, 1517-1524, (2017) doi: 10.1201/9781315100333-201

Petit, C., Chabot, A., Destrée, A., Raab, C.: Interface Debonding Behavior. In: Buttlar, W., Chabot, A., Dave, E. V., Petit, C., Tebaldi, G. (eds) Mechanisms of Cracking and Debonding in Asphalt and Composite Pavements. RILEM State-of-the-Art Reports, vol 28: 103-153. Springer, Cham (2018)

Sedran, T., Gennesseaux, E., Waligora, J., Klein, P., Nguyen, M.L., Cesbron, J., Ropert, C., Monnier, L.: Development of a Permeable Removable Urban Pavement. 14th International Symposium on Concrete Roads, Krakow, Poland (2023)

Tschegg, E. K. Equipment and appropriate specimen shapes for tests to measure fracture values, AT No. 390328, Austrian Patent Office, Vienna, Austria (1986)

Tormos, S., Chabot, A., Dave, E. V.: A Review of Urban Heat Island-Reducing Pavement Types and Thermal Properties. In: Carter, A., Vasconcelos, K., Dave, E. V. (eds) 14th International Conference on Asphalt Pavements ISAP2024 Montreal. Springer, Cham (In press)

Period: 5-6 months, preferred to end by July 2025

Context: online progress meetings with teams from UGE (France) and UNH (USA) will be routinely conducted

Qualifications: Good level in solid mechanics since bachelor and Master1 degree, a curiosity and a pronounced interest for research are required. A knowledge of DIC and a good level of English and French will be considered a plus.