Dredge material today is seen as a valuable resource, and innovative methodologies for its beneficial use are in the infancy stage of development worldwide, Cole and Kobelo write. “It has been determined that due to the physical and chemical composition of dredge material; it can be compatible to typical filler used in concrete production,” they say. “Dredge material used as filler in road construction would not only be a more economical choice, but it would provide a sustainable use for a naturally occurring material.”
Dredged material, as filler, may be useful in a wide spectrum of applications due to the fact that it includes predominantly modified clay and sand, the writers add. “Inorganic materials, such as limestone and quartz, are used as mineral fillers in the process of concrete production,” say Cole and Kobelo. “The largest segment of dredge material is quartz, and it is also the most common ingredient of concrete. The clay/silt fraction encompassed in dredge material exhibits the same characteristics found in mineral fillers and therefore can be incorporated into concrete production as a sustainable resource.”
Fillers are widely used for the construction of composites to modify properties in order to fill out voids within the particles, they conclude. “Dredge material is able to duplicate the same properties of traditional mineral fillers and provide strength and volumetric stability. Due to this assessment, dredge material, as aggregate replacement in concrete applications is a viable solution opposed to its problematic disposal…[but] more testing needs to be completed in order to see how feasible this is for large-scale applications.”
To read more about warm-mix asphalt, check out the March issue of Better Roads.