Bituminous materials
Introduction
Bituminous materials are black, solid or viscous, ductile substances that soften with heat. They include both those of petroleum origin (crude) and those obtained by destructive distillation of carbonaceous substances (derived from petroleum).[1].
Historical review
These are some of the oldest construction materials that exist; already used in Mesopotamia and the Indus Valley (3800 BC). Natural bitumen was used in road construction, masonry and other uses.
Although the first products used were natural bitumens, with the passage of time and the advancement of science, their use has been reduced in favor of chemical bitumens from the distillation of oil or coal.
Guys
Contenido
Los materiales bituminosos pueden dividirse en dos grandes grupos: betunes y alquitranes.
Ambos presentan unas propiedades análogas y de diferencias muy significativas: los dos son termoplásticos y poseen una buena adhesividad con los áridos; sin embargo la viscosidad de los alquitranes se ve más afectada por las variaciones de temperaturas y su envejecimiento es mucho más precoz que el de los betunes.
Bitumens
They are mixtures of natural hydrocarbons, pyrogenated (subjected to heat treatments), or combinations of both. They can present various states: gaseous, liquid, semisolid, and solid. Furthermore, and as we have already mentioned, they can be natural or artificial.
It is worth highlighting within the various types of bitumen, some of them of special interest such as asphalt bitumen. These bitumens, prepared by distillation of natural hydrocarbons, appear as solid or semi-solid at room temperature, so in order to use them on construction sites, they must be heated in order to reduce their viscosity.
Other types of bitumen are:
Some authors classify the types of bitumen differently, with another possible classification being the following: primers, which are used for surface preparation; bituminous glues and adhesives, which are used to join waterproofing products or elements; bituminous mastics and reinforcement, which are used to carry out waterproofing in situ; materials for sealing joints; and prefabricated products such as sheets and plates.