Field Evaluation of Crushed Glass–Dredged Material Blends

Based on the laboratory results reported in a companion paper, three crushed glass–dredged material (CG–DM) blends were prepared and evaluated in the field to explore the feasibility of using CG–DM blends in general, embankment and structural fill applications. A trailer-mounted pugmill successfully prepared $20∕80$ , $50∕50$ , and $80∕20$ CG–DM blends (dry weight percent CG content reported first) within a tolerance of $\pm 5$ dry % by weight of the targeted percentages. Blending criteria were routinely met at pugmill throughputs up to $\mathrm{1,500}{\mathrm{m}}^3∕\text{day}$ . The constructed $20∕80$ CG–DM embankment was compacted to a minimum of 90% modified Proctor compaction, whereas the $50∕50$ and $80∕20$ CG–DM embankments were constructed to a minimum of 95% modified Proctor compaction. Twenty to 80% CG addition to DM resulted in $1.5–5.5\mathrm{kN}∕{\mathrm{m}}^3$ increases in field dry densities above 100% DM, densities not achievable with other DM stabilization techniques such as Portland cement, fly ash, and/or lime (PC/FA/lime) addition. CG substantially improved the workability of DM allowing construction with conventional equipment and three person crew while achieving very consistent and reproducible results during a timeline of frequent and heavy precipitation events. The $20∕80$ , $50∕50$ , and $80∕20$ CG–DM embankments were characterized by average cone tip resistances on the order of 1.0, 1.5, and $2.0\mathrm{MPa}$ , respectively. An environmental evaluation of 100% CG, DM and $50∕50$ CG–DM blend samples coupled with an economic analysis of a scaled-up commercial application illustrated that the CG–DM blending approach is potentially more cost effective than PC/FA/lime stabilization approaches. These features of CG–DM blending make the process attractive for use in urban and industrial settings.