Beneficial reuse of Brest-Harbor (France)-dredged sediment as alternative material in road building: laboratory investigations

The practice of waste utilization as secondary raw material in the field of civil engineering is promoted due to the scarcity of natural aggregates. The beneficial reuse of marine-dredged sediments in road construction is the focus of this article. Mixtures of raw sediments and dredged sand were collected from Brest Harbur (Bretagne, France) and were treated with road hydraulic binders. In accordance with the French Technical Guidelines for soil treatment with lime and/or hydraulic binders, formulation were prepared and characterized. For both the hydraulic binders, mechanical resistance results are quite similar; this suggests a similar reactivity with the studied sediment sample. However, regarding sustainability parameters, some discrepancies can be noted. Case in point, for the mixtures treated with cement containing more glass-forming oxides (SiO₂+Al₂O₃) and fluxing (Fe₂O₃+CaO+MgO+K₂O+Na₂O), water resistance after immersion at 40°C is significantly better. Furthermore, as observed in scanning electron microscopy analyses, both the hydraulic binders can lead to swelling in the road materials. In fact, volumetric swelling of treated samples was indicated in microscopic observations - a phenomenon that is largely influenced by the presence of water in pores material on the one hand and by ettringite quantity on the other.

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  • English

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  • Accession Number: 01671790
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Mar 23 2018 3:47PM