Source: {"pile_set_name": "USPTO Backgrounds"}

The physical and chemical properties of cementitious bodies are varied to suit the requirements of a range of applications. For example, cementitious bodies are formed into panels for use in the construction of walls, floors, ceilings and roofs. The panels are usually made of concrete which is formed by mixing a slurry of cement and aggregate material and/or sand. The slurry is cast into a mold and cured to form a solid concrete panel.
It is known that by controlling the composition of the slurry the physical properties of the solid panel can be predetermined. For example, by casting a slurry containing dense aggregate materials a panel with improved structural properties results. Alternatively by casting a slurry containing light weight aggregate materials a panel with improved thermal and acoustic insulation properties results.
Multi-layered concrete panels are formed by casting and curing a first layer of concrete and then casting and curing subsequent layer(s) of concrete atop the first layer. By pouring multiple layers of concrete the physical properties of the concrete panel can be refined. For example a panel can have a first layer of light weight aggregate material to provide thermal insulation and a second layer of dense aggregate material to provide structural strength. However, these multilayered panels are expensive to produce as they require multiple casting and curing steps. Further, there are performance weaknesses associated with the boundaries between the successive concrete layers.
In this specification, where reference has been made to external sources of information, including patent specifications and other documents, this is generally for the purpose of providing a context for discussing the features of the present invention. Unless stated otherwise, reference to such sources of information is not to be construed, in any jurisdiction, as an admission that such sources of information are prior art or form part of the common general knowledge in the art.