The Use of low density Polyethylene carry-bags waste in Hot Asphalt paving mixtures

Abstract

This paper reports an investigation on the effect of shreded low density polyethylene (LDPE) as a
bitumen modifier on the permanent deformation of asphalt concrete using Marshall Design parameters. The
parameters assessed include the compacted hot-mix density, the percentage of air voids in the mixture, and in the
mineral aggregate, the percentage of voids filled with bitumen, in addition to Marshall Stability and flow. The
effect of LDPE on some physical properties such as penetration, softening point and ductility was also
investigated. Bitumen was mixed with the LDPE 2 - 10% by weight of bitumen at 160-180°C and it was found
that Marshall Samples prepared with the modified binder provide the specification limits and that using higher
percentage of plastics waste causes the polymer to separate from the blend. A modified technique was developed
where the stone aggregate was coated with molten LDPE(10-25%) , the plastics waste coated aggregate (PCA)
was then used as the raw material for flexible construction. PCA shows better binding properties. It has less
wetting property with much less voids and higher Marshall Stability value.