Exposed aggregate in Perth is a technical term for an aggregate that has been damaged and then crushed by the weather. While technically classified as “organic” material, it is still considered a non-hazardous material. In most situations, exposed aggregate refers to pulp mill waste. This material is usually treated to stabilize its viscosity. This treatment can be done chemically, by increasing the density of the material, or by using an exothermic process to break up the material, allowing it to form into granules and resins that are lighter and more easily compacted into other items.
Exposed aggregate in Perth – How to get an Exposed Aggregate Finish on Concrete
For some pulp mill waste, there is nothing too exposed. When this type of aggregate material is used in masonry construction projects or for concrete pour surfaces, it is often left on the surface of the surface. Most materials that have been exposed or are natural wood chips are not permitted for use in masonry and other concrete structures. The use of such materials is prohibited by the US Bureau of Land Management (BLM) and the US Forest Service.
There are a number of reasons why exposed pulp mill waste and other natural wood materials are not allowed for use in masonry or other concrete. One of the main reasons is the potential for expansion and contraction of the materials, resulting in the cracking or snapping. Exposed pulp mill waste has a lower compressive strength than other types of wood.