Panel structures are used to create interfloor ceilings in the construction of private houses and multi-storey buildings. They have different technical parameters, operational properties and installation possibilities, which ultimately determine the purpose of a particular product. There are also universal requirements for floor panels, which come down to optimal mechanical strength, heat and noise insulation, durability, etc.
Panel manufacturing materials
The production uses concrete, metal, stone, brick and wood, as well as combinations of these materials. Concrete is more often used as a structural basis in various designs. Stone and brick floors are used in individual construction and are considered the most wear-resistant filling for the form of this design. However, for the manufacture of such floors, special expensive technologies are used, so they are usedless often. Usually, on this basis, wall panels of a small form are made. For horizontal structures, concrete with elements of metal reinforcement is mainly used. The group of panels is largely formed by sawn timber or chipboard waste. Solid wood is used for the floor beams, while thin sheets act as an external cladding, covering and laying insulating material in empty niches.
Panel structure
Concrete elements are usually made on monolithic or prefabricated bases, but the structure in both cases is formed by cement-sand mixtures reinforced with metal rods. It turns out a reinforced concrete slab, which may include additional functional devices. Sandwich floor panels are made from wood material, which usually consist of several layers. Again, each layer can be made from a solid billet or chipboard. In some models, the core is filled with an insulating material - insulation, waterproofing or noise-reducing layer.
Features of SIP panels
Overlappings from this material were originally used in frame houses made according to Canadian technology. But their technical and operational advantages have expanded the scope. After optimization and adaptation to Russian conditions, SIP panel technology has become popular in the segment of individual construction.
Todaysuch structures are made of a connecting beam, which, before processing, undergoes chamber drying to a moisture content with a coefficient of 12%. According to the structure of the ceiling from SIP panels, they are an insulating sheet, including a heat-insulating layer and two protective OSB coatings on both sides. Connections are made using polyurethane adhesive, which is pressed at the factory under a pressure of about 20 tons. There are also various variations of SIP panels, which are made from chipboard layers, chipboard and insulating polystyrene foam.
Actually, the main operational advantages of such ceilings remain unchanged - effective thermal insulation, thermal barrier, ease of installation and low price. The disadvantages of SIP panels are expressed in flammability, susceptibility to biological destruction and environmental hazards. The last negative factor is due to chemically unsafe binders like the same polyurethane. Conversely, protection against fire, fungus and mold is enhanced by the use of special impregnations for wood.
Features of CLT panels
Another, but more modern variety of wood sandwich panels, which is used in both the private and industrial sectors. This is a structural element obtained in the process of cross-gluing solid wooden lamellas, also under a multi-ton press. Such slabs are closer to reinforced concrete floors in terms of strength and durability than SIP panels. Butand in addition to structural reliability, this material has many positive qualities - more precisely, combinations of operational properties. For example, the technical stability of a CLT floor panel is organically combined with protection from thermal influences and the influence of aggressive chemical environments. There are other advantages over rigid concrete slabs. In particular, the flexibility of the lamella structure allows them to withstand both static and dynamic loads, which is especially important for regions with seismic activity.
Types of reinforced concrete panels
The traditional segment of concrete floors is also not limited to standard versions. To date, the following types of floors of this class are used:
- Frequently ribbed. Ideal for large buildings where conventional concrete structures can sag. Stiffening ribs eliminate the risk of deformation.
- Monolithic. An element that is quite difficult to manufacture and install, but it also provides more structural possibilities for the installation of interfloor partitions. For example, reinforced concrete floor panels with a monolithic structure can be installed in rooms without a single load-bearing wall.
- Teams. Both often-ribbed and standard monolithic segments of reinforced concrete slabs can be laid as a basis, and the peculiarity will lie precisely in their combination. The overlap can be formed in separate parts, both through reinforcing ligaments by welding, and using the cement-sand joint technology.
Specifications
Floor parameters are approved by SNiP standards. So, with a heater thickness of 100 mm, the heat transfer resistance should be 2.8 W / (m ° C). If panels with a standard thickness of 224 mm are used, then the value of thermal resistance will be already 5.2 W / (m ° C). Optimum parameters of insulation and resistance to various microclimatic influences are achieved due to the material of the middle layer. As a rule, in multilayer structures, mineral wool or polystyrene foam insulation is used.
The size ranges of floor panels can be represented as follows: thickness from 60 to 250 mm, length from 900 to 3600 mm, and width from 600 to 2500 mm on average. The mass indicator is also very important in the calculations. Depending on the material of the ceiling design, the weight of 1 m2 of the structure can vary from 220 to 450 kg. Again, we are talking about average standard values, but the standards, depending on the operating conditions of the structure, allow going beyond these limits.
Panel reinforcement
Wooden products in the traditional sense of this reinforcement technology are not reinforced. After installation, they can be strengthened with ties, bandages or metal clamps with stiffeners, but the rods are not introduced into the structure itself. In reinforced concrete floors, various types of thermomechanically hardened reinforcing steel are used. It improves structural stability and durability. There are also multi-hollow floor panels without reinforcement. Cylindricalvoids with a diameter of 60-90 mm themselves add mechanical resistance to the product, performing a function similar to the same stiffeners. Another plus of free niches in the structure of reinforced concrete floors is to reduce weight.
Installation technology
Reinforced concrete slabs and wood panels are mounted differently. The first are installed with a crane on a prepared site with a cement-sand mortar on the walls. The load-bearing supports are completely covered by a solid platform of the structure without gaps. Crane operators, slingers, as well as a group of assistant workers are involved in the work. It is easier to install floor panels, which is implemented using a groove joint system with the inclusion of self-tapping screws. For such structures, I-beams with profile grooves are pre-installed, into which the floors are inserted. Further, with the help of self-tapping screws, the structure is finally fixed in the technological niche.
Pros and cons of panel structures for overlapping
Among the advantages of wooden panels, many note low cost, ease of installation and resistance to dynamic loads. Although such structures lose to reinforced concrete in terms of strength and rigidity, in seismically hazardous areas, the flexibility of wood-based materials turns out to be a very valuable characteristic. If we talk about the shortcomings, then the floor panels of this type are very sensitive to fire and biological destruction. Of course, technologists also calculate such nuances, processing the structure of the material accordingly. Butand during operation, the user himself will have to regularly monitor the state of the structure, performing procedures for its comprehensive protection with special means.
Scope of panels
Target objects of using this design are wooden buildings. Initially, panel multilayer ceilings were introduced into prefabricated house sets, but today they are used in traditional buildings from glued laminated timber, and not only. Cinder block and aerated concrete houses with light frame loads can also be built using wooden floor panels. Concrete slabs just turn out to be an undesirable solution due to their large weight, and, for example, dense CLT-lamellas will suit the developer both in terms of rigidity and weight. This material is also used in laying foundation sites, forming a supporting base for small outbuildings.
Conclusion
It cannot be said that new technologies for installing floors are replacing the methods of their traditional arrangement with reinforced concrete structures. Nevertheless, the capital construction of multi-storey buildings and large industrial facilities is not yet considering wooden floor panels as a full-fledged replacement for conventional solid-state slabs. But in the private segment, the transition to prefabricated frame structures naturally leads to the use of the same SIP elements. They not only meet the requirements of individual suburban housing construction, but also organically fit into the concept of ecological houses, albeit with some nuances. Otherthe fact is that there is also a technology for installing beam ceilings, which also has many advantages of installing wooden panels, making them a serious competitor.
