Order the cutting of sandwich panels only after the actual measurement of the mounted frame, as tolerances on metal structures can be up to 10-15 mm.
The carrying capacity of the frame is often insufficient when ignoring the snow load in a particular climatic area, which leads to deformation of the pillars and depressurization of the joints. Designing steelwork It requires accurate cross-sectional calculations, as the wrong choice of metal thickness or column pitch entails a critical reduction in the stiffness of the entire building. Engineers must consider not only the weight of the wall and roofing itself, but also wind pressure, as well as the weight of the hanging equipment if it is planned indoors.
The standard step of columns of 6 meters is optimal for most industrial facilities, however, when using light farms, the span can be increased to 12 meters or more. Lightweight metal structures allow to reduce the construction time of the building by many times compared to traditional brick or concrete construction, but require strict adherence to the assembly technology. Each mounting node, from the flange joint to the roof screw, should be designed to transfer forces without the occurrence of local stresses that can destroy a thin sheet of sandwich panels.
The basis of durability of prefabricated building is high-quality anticorrosion protection metal-frameespecially in aggressive industrial environments or in coastal areas. Modern designs often involve the use of galvanized steel or the application of multi-layer paint coatings, which significantly increases the life of the facility without the need for frequent maintenance. Properly assembled frame provides perfect wall geometry, which is critical for sealed mounting of the cladding.
Types of frames and materials used
The choice of the type of frame directly depends on the purpose of the building, the required spans and the budget constraints of the customer. The most common solution for warehouses, hangars and shopping centers are frame structures, where rigidity is ensured by rigid connection of columns and rigs. Construction from sandwich panels On the basis of such frames allows you to create large interior spaces without intermediate supports, which is convenient for placing production lines or warehouse equipment.
For objects with less requirements for internal volume, arched structures or frames of LSTK (light steel thin-walled structures) are often used. Arches have a high load-bearing capacity with minimal metal consumption, but limit the useful height of the walls. In turn, LASTK It is collected from thermoprofiles, which excludes cold bridges, but its use is justified mainly for buildings of small storeys and span.
The material for the main bearing elements is most often steel brand St3 low-alloy steel 09G2CIt has a high durability and frost resistance. Cross sections of the elements can be made of double-taurs (welded or hot-rolled), channelers or profile pipes. Selection of cross-section metal-frame is made at the design stage, taking into account all loads, including installation, and is fixed in the drawings of the CM (metal structures).
⚠️ Attention: The use of rolled metal with a thinner wall, as indicated in the project, is unacceptable, since this reduces the stability class of the structure and can lead to its addition.
Load calculation and design of nodes
Designing starts with load collection, where the main parameter is the weight of 1 square meter of sandwich panels used, which varies from 15 to 25 kg depending on the thickness and type of filler. To the own weight of the enclosing structures is added the weight of the elements of the fastener, drainage system, as well as technological equipment placed on the roof or walls. Calculation of metal structures It also needs to take into account temporary loads, such as snow and wind, the values of which are taken from zoning maps for a particular construction site.
Particular attention is paid to node connections, since they transfer the effort from one element to another. Flanged connections of columns with foundation, joints of rigs and connections between farms should be designed for cutting and crumpling. Vertical and horizontal structures are used to ensure the spatial rigidity of the building. linkagewhich prevent the frames from moving in the longitudinal direction.
| Type of load | Description | Impact on design |
|---|---|---|
| Permanent. | Weight of metal structures, sandwich panels, communications | Determine the basic cross-section of elements |
| Snowy | Weight of snow cover on roof | Critical for calculating farms and runs |
| Windy | Wind pressure on the facade and roof | Influences calculation of connections and anchoring |
| Crane | Load from bridge cranes (if any) | Requires reinforcement of columns and foundations |
The result of the design is a set of drawings CM, which is being examined. The drawings detail all sections, types of welds, bolt diameters and strength classes of the fastener. Quality project allows to minimize metal intensity, reducing the cost hangar-buildingAt the same time, ensuring the safety of operation.
What is the strength class of bolts?
Bolts for metal structures are marked with two digits (for example, 4.8, 8.8, 10.9). The first digit multiplied by 100 gives the tensile strength in MPa, and the second, multiplied by 10, gives the yield limit as a percentage of the strength limit. For load-bearing nodes, bolts of class 8.8 and above are usually used.
Stages of installation of a frame building
Installation begins with the preparation of the base and installation of anchor bolts, which must be exposed with high accuracy. Any deviation in the position of anchors will lead to problems when installing columns, so geodetic control at this stage is mandatory. After solidification of the foundation, the elements are delivered. frame to the site where their layout is performed in the order reversed installation.
The assembly of the spatial unit is usually carried out by means of a crane. First, columns are installed and temporarily fixed, then rigs or farms are mounted on them. Immediately after the installation of the first cell, it is necessary to establish rigidity bonds so that the structure becomes stable. Further installation metalwork is carried out in sections, followed by tightening of bolt connections and control of geometric parameters.
☑️ Checklist before panel installation
An important stage is the installation of secondary elements: runs, wall rigs and half-timbered. This is where the sandwich panels will be attached. The step of runs should strictly correspond to the length of the panel or be multiple to it to avoid unnecessary joints. Unevenness on the surface of secondary structures should not exceed the permissible norms, otherwise wall-pan They will not lie tight, and the tightness of the contour will be broken.
⚠️ Attention: It is forbidden to carry out welding work in the immediate vicinity of already mounted sandwich panels in order to avoid their damage by sparks and thermal deformation.
Specifics of fastening sandwich panels
Mounting the cladding to the metal frame is made with the help of special self-cutting screws with a polymer coating and a press washer. For the roof, fasteners with an increased length and pitch of thread are used, providing reliable fixation in the shelf of the run. Installation of sandwich panels requires the observance of the sequence: first, corner and basement elements are installed, then the main sheets are laid from the bottom up (for walls) or along the slope (for roofing).
Particular attention should be paid to the design of the adjoining nodes, since these places are the most vulnerable to leaks and blowing. The use of high-quality sealing tapes and sealants allows you to create a continuous thermal insulation circuit. When installing, it is necessary to control the tightening force of the screw: insufficient force will not ensure tightness, and excessive can push the metal panel or damage the seal.
The technology of docking panels involves the use of lock connections of the type "thorn-pases", which are further sealed. Vertical and horizontal joints must be protected from moisture. Properly mounted cladding on sandwich-frame Not only does it protect the room from the cold, but it also works as part of the load-bearing system, perceiving wind loads and transferring them to the half-timbered.
The main principle of installation is compliance with temperature gaps, since sandwich panels have a high coefficient of linear expansion.
Anti-corrosion protection and durability
The durability of a prefabricated building depends on the quality of metal protection from corrosion. In factory conditions, metal structures usually undergo crushing blasting and are painted with soil-enamel. However, during transportation and installation, the coating can be damaged, so all defects must be repaired before mounting the panels. Protection of metal structures It is not just an aesthetic, but a necessity that extends the life of a building to 50 years or more.
For aggressive environments, such as chemical production or the sea coast, special painting schemes with an increased number of layers are used or hot galvanizing is used. Galvanizing provides cathodic protection of steel, preventing the development of corrosion even in scratching areas. In choosing metalwork For such objects, saving on metal protection is unacceptable, since replacing rotten elements will require dismantling the entire cladding.
Regular maintenance involves a visual inspection of the mounting units and the condition of the paint coating. If corrosion foci are detected, it is necessary to clean the damaged area and cover it with a protective composition. Timely care load-bearing This will prevent costly repairs in the future.
Cost and cost-effectiveness
Price. metalwork under sandwich panels It is formed from the cost of metal, the complexity of design solutions and the volume of work on manufacture. The use of light steel structures reduces the load on the foundation, which leads to a reduction in the cost of concrete work. In addition, the high speed of construction of such buildings reduces the payback period of the project, allowing earlier to start operation of the facility.
When comparing the cost per square meter, you should take into account not only the price of materials, but also the cost of installation. A skilled team will assemble the frame faster and with fewer errors, which will eventually cost less to fix the marriage. Investments in quality projects and materials are paid off by reducing the cost of heating and repair.
⚠️ Attention: Cheap metal structures made of substandard metal may not withstand the estimated loads, so require quality certificates for rolled metal.
The economic effect of construction is also achieved through modularity. The building can be easily expanded by adding new sections, or dismantled and moved to another location. This flexibility makes it possible to quick-build One of the most attractive solutions for business.
What does the final price depend on?
The total cost depends on the current rate of metal, the region of construction (snow-wind load factor), the height of the building and the availability of crane tracks.
Frequently Asked Questions (FAQ)
Which column step is optimal for a warehouse?
The optimal step of columns for storage facilities is 6 meters. This allows you to use space efficiently and minimize the consumption of metal for runs and connections. However, there are options with steps of 12 meters when using more powerful farms.
Do I need to insulate the metal structures?
The metal structures themselves are not insulated, since they are a power frame. The insulation is sandwich panels, which are mounted outside. It is only important to prevent the formation of cold bridges in the mounting nodes.
How long does a sandwich panel building last?
The service life of the building directly depends on the quality of anticorrosion protection of the frame. With proper care and the absence of an aggressive environment, operation can last 50 years or more. Sandwich panels may require replacement or repair in 25-30 years.
Can we build in the winter?
Yes, the technology of installation of metal structures and sandwich panels allows you to build all year round. "Wet" processes are present only at the stage of foundation construction, which is desirable to complete before the onset of frosts.