We live in a world in which almost every single plastic piece created still exists because this material lasts for about four centuries. It became an environmental issue that could be contrasted with some actions in daily activities, personal and professional. That means that is a problem everyone should face also in the professional area, for that reason this thesis will describe one way in which the civil engineering can approach the previous formulated problem: it is possible to construct asphalt roads having a percentage of waste plastic, treated in particular ways that improve some of the properties of the road such as the resistance, stability and durability.