This product is mostly used in high-rise buildings, because in the design and construction of such buildings, a reasonable reduction in the weight of materials (dead load) is considered, which can be achieved by using this product, because the weight of one square meter of brick wall 22 cm with cement sand mortar and lined on both sides is more than 450 kg, while one square meter of the middle wall with fin (concrete type) coatings weighs less than 150 kg, and of course the use of foam to reduce the dead load of the building Will be followed by high-ranking officials in a dramatic way. Foam panels can be built in one or two-storey buildings without the use of steel structures and can be used as load-bearing walls, and the roof can be used. Aircraft have an efficient and reliable use.
Description of the structure consisting of 3D panel (what is 3D panel)
3D lightweight prefabricated panel system (3D Panel) consists of two welded steel mesh panels with an insulating core (polystyrene foam) in the middle and connected to each other by a number of truss members, which after Installation, concrete is sprayed on both sides.
The scope of application of 3D style prefabricated panels (3D Panel) is classified as follows:
In the form of load-bearing walls or horizontal diaphragms as load-bearing structures of the building
Non-load-bearing partition walls
As a shear wall in conventional concrete and metal structures for lateral bearing
Introduction of 3D panel in construction
In the northern United States, many people lose their homes every year due to severe storms. One of the worst hurricanes occurred on October 20, 1992 in South Florida. After the storm subsided, the prefabricated 3D buildings withstood the storm at 190 kilometers per hour and suffered no damage. While some structures in the area were severely damaged. At the University of California, California, all exterior walls were built based on 3D sandwich panels. On June 28, 1992, a magnitude 6.9 earthquake shook the region of California, 80 kilometers from the epicenter of the university building. The building was reportedly unharmed by the quake, which lasted a full minute. In general, 3D panel buildings show very good resistance to lateral forces with two earthquakes. In this article, we will introduce prefabricated houses, 3D panels and how to implement them.
The 3D panel system is designed based on ideas such as cover structure, durability, fire insulation, sound and internal humidity, access to more usable space, energy optimization, resistance to lateral wind and earthquake forces. This system is actually a light semi-prefabricated method for making reinforced concrete structures.
A 3d structure consists of a panel with expanded Eps (polystyrene), on which two layers are welded steel mesh and are connected to each other by a series of truss elements, and after installation to a thickness of -40. 80 mm is shotcrete with concrete.
If the shotgrit is 40 mm thick, the distance between the polystyrene and the mesh mesh is considered to be 20 mm, which is filled with shotgrit and the remaining 20 mm thickness of the shotgrit covers the outer surface of the mesh. It should be noted that this operation is performed for two levels of the panel.
The 3D structure derives its double strength and coordination from the concrete frame and diagonal wires. These panels are used as wall and ceiling elements of the building. In addition to the role of separating the architectural space, the panels also act as a vertical load-bearing wall and cut against lateral loads, and the resistance obtained by connecting the meshes to each other is used to withstand earthquakes and strong winds.
How the elements behave and carry
The wall elements are designed for shear load and are controlled for axial load (column behavior) and flexural anchor. Recent research on 3D sandwich panels has mostly focused on vertical loads, layer cutting or bending tests. Bending tests have shown that in cases where the welded mesh is subjected to tensile bending, it causes brittle rupture due to the small cross-section of the steel and their weakening at the weld, which leads to stress concentration.
In these cases, the use of auxiliary rebars in the parts that fall into the tension significantly reduces the rupture. Also, reinforcement reinforcement should be installed at the joints and next to the openings according to the design. The foundation of these structures is made of strip or wide and the individual foundation is not used in these structures, waiting reinforcements are installed at the location of the walls and the sandwich panels of the wall are restrained.
The floor panel acts as a one-way slab and this is due to the presence of cutting members in the longitudinal direction of the panel. These panels are placed next to each other and mounted on the wall panels and secured by waiting fixtures. Polystyrene layers act as molds for concreting as well as thermal and acoustic insulation. The roof panels form a rigid diaphragm. Lateral loads caused by wind or earthquake are distributed through the rigid diaphragm with relatively stiffness between the walls.
