Green pavements: reuse of plastic waste in asphalt mixtures
Nowadays, the disposal of plastic waste is an issue of major concern worldwide because of its considerable volume and growth. An option to tackle this problem is to recycle this waste. This alternative reduces the quantity of net discards, conserves both material and energy and provides a comparatively simple way to make a substantial reduction in the overall volume of solid waste. The purpose of this study is to investigate an environmentally friendly approach about the influence of recycling different percentages of urban and rural plastic waste by adding them in a dry process on an asphalt mixture, through a comparative laboratory study. The resulting mixtures are analyzed considering their volumetric parameters and the values from diverse laboratory mechanical tests. The performance tests include, Marshall stability, Marshall quotient, indirect tensile strength, fracture energy, resilient modulus, permanent deformation and creep compliance, which were carried out on unmodified and modified hot asphalt mixtures. The obtained results are presented and discussed in this paper showing that the reuse of recycled plastics in asphalt mixtures is a viable alternative that contributes to the reduction of plastic wastes as well as the protection of the environment.
Polyethylene from silo bags
Silo bags are big plastic bags for low cost on-farm storage of grains, which are approximately 60–80 m long and 3–4 m in diameter as shown in Fig. 1. These plastic bags are made from a membrane combining three very thin layers of a low-density polyethylene (LDPE), a HDPE and a UV resistant layer containing titanium dioxide. After several uses and due to the damage produced by the weather, loading equipment rodents and birds, silo bags must be replaced and then large amounts of polyethylene are available for recycling.
The recycling process is made in a recycling company where first the polyethylene is washed and dried. Then, two types of RPE are produced: a chopped RPE in scales or flakes with a maximum size between 6 and 10 mm and pellets with sizes between 2 and 5 mm . Both types of RPE were considered in this study and were incorporated in a dry process during the mixture preparation .
Recycled polypropylene (PP)
Polypropylene is present in a wide range of products like bottle caps, bags, appliance parts, toys, medicine and food containers, among others.
The recycling process takes place in special processing plants and the final product may have different shapes.
Civil Scholar is a Blog by Aravind Samala on Construction, Environment, Technology, Trends and Innovation.