DESIGN AND USE OF A NOVEL TEST APPARTUS FOR RETENTION OF FINE DREDGED FILL

This paper will discuss the problem of retaining fine sand in reclamations protected by rubble mounds with geotextile filters. It formed part of a wider study that will be presented at this conference by Dimakopoulos et al., where the hydraulic gradient at the reclamation / landfill will affect retention of the sand. In particular, we will describe the design and application of a novel test device to identify sand retention in experiments on an example sand sample and geotextile subject to reversing heads. It also directly follows on from the work by Cantelmo et al 2011 and Polidoro et al 2015, where hydraulic gradients in the core were examined during the assessment of the extent / suitability of the retention method. The paper will summarise numerical modelling to derive appropriate hydraulic gradients (Dimakopoulos et al.), the design of the test device using relatively easily obtained materials, and the use in a forensic failure study.