Aluminum Waste in Road Pavement Subgrade

This paper aims to investigate the use of spiral aluminum computer numerical control milling waste (CNC-W) in the construction of road pavement subgrade. The soil (CL) was mixed with CNC-W spirals with ratios of between 0% and 20%, and 5 percent increments by dry weight with different water contents. California Bearing Ratio (CBR), Unconfined Compressive Strength (UCS), and consolidation tests were conducted. The experimental results indicated that the inclusion of CNC-W spirals increased the CBR value of clay up to the 15% mixture ratio, then decreased it. Similarly, the UCS value of clay was increased to the same ratio, whilst the UCS was not able to be determined due to the failing of all specimens with a mixture ratio higher than 15%. The permeability and swelling values, as well as the consolidation characteristics of the mixtures, were defined. The swelling percentages decreased from 1,15 cm/sec to 0,81 cm/sec with an increment in the CNC-W spiral content. A reduction was observed in the coefficient of permeability (k) values up to 15% mixture ratio, whilst it remained constant with change in CNC-W spiral content with a 20% mixture ratio. Coefficient of consolidation demonstrated a similar pattern of behavior to the permeability changes.