A 3D panel consists of a three-dimensional welded wire space frame provided with a polystyrene insulation core. Such panel is placed in position and wythes of concrete are applied to both sides. With varying thickness, such panel is sandwiched between two plane-paralleled welded wire mesh sheets. These sheets are positioned by uniformly distributed inclined “cross wires”, that pierce through the EPS core and are welded at both mesh interfaces.
This results in a lightweight, three-dimensional truss system with high inherent stiffness. The standard width of 3D panels is 1.20 m while the element’s length is variable and depends on the corresponding field of application. 3D panels are delivered as positioned elements to the site where they are connected easily as wall and slab structural elements.
In the 15 largest cities of the world alone, a demand for more than 100 million homes with the necessary infrastructure will arise in the 15 years to come. The fast-growing population triggers the need for a new, cost-conscious building system to satisfy the tremendous demand on low-cost housing in the world. The requirements this building system has to fulfill are the following:
Fast and easy erection with unskilled labourers
Economical use of local materials
Structurally stable construction
Good thermal and sound insulation
Use of prefabricated elements produced on an industrial scale (thus, low cost)
Great variety of design features
Minimum installation work on site (no cranes)
Traditional building methods, such as brick, concrete, steel and prefab comply only partly with these requirements. In the early 1960´s, the idea of using a three-dimensional panel with insulation material sandwiched between two layers of welded wire fabric came up in the United States. While the idea was sound, technology did not exist to economically and efficiently mass-produce the panels, utilizing the most economical insulating and reinforcing components.
Attempts have been made over the years to design a process to automate the manufacture of a welded wire sandwich panel. EVG, an Austrian company known worldwide for the manufacture of complete mesh welding plants and special equipment, have designed and patented machinery specifically to mass-produce 3D panels. The breakthrough of EVG’ s development is the use of Polystyrene sheets in module size. The spacer wires are diagonally pierced through the plastic foam core and welded to the two mesh layers. The spacer wires hold the core firmly.
The panels produced by using EVG equipment are extremely rigid and ready for field installation. EVG’ s novel method combines the desired requirement listed above with a cost conscious production.
