The 12th International Conference on Scour and Erosion (ICSE 2025)

We propose a remediation technique to stabilize soils eroded due to suffusion. The method involves reinjecting fines into a coarse-grained sand matrix and the injected fines are expected to improve the mechanical stability by providing lateral support to the existing force chains in the material. In this regard, a coarse Hostun 1/2.5 sand with D15 of 1.37mm is injected with Fontainebleau fines sand (NE 34) belonging to 5 different fines size regimes starting from R (D15/d85) = 4.6 to 11.3. We then determine the total fines content and also the fines profile within the injected sample. For small R values we obtain an exponentially decaying fines profile which becomes linear with increasing fines content. We then extract the average infiltration distance of the fines from the above profiles which is observed to vary linearly with size ratio. Further we also test the effect of shape of injected fines and we find that both the amount and infiltration distance is lower for more angular fines (Hostun HN34). The injected samples are then subjected to triaxial tests to assess the impact of injected fines on the mechanical stability by comparing it with non-injected and samples reconstituted at the same fines content as the injected sample.