Despite the reduction in costs in the construction industry, consumers still generate fairly decent revenue for companies producing building materials. Now many people are buying necessary materials For self-construction, the same applies to metal beams, metal is one of the most durable and affordable bases for the foundation and frame of a building.
What are beams and what are they made of?
The beam is important element in the design, it is placed to increase stability and strengthen the structure. Metal beams are most often made of steel, their action is aimed at bending. If the structure is too massive, then the beam is made of an I-beam, it looks like two connected letters t. With this cross-section, the load on the material is distributed evenly and the resistance increases.
Beams are not only made of metal compounds, there are also wooden ones, they are used in more simple construction, they cannot be manufactured with different types sections, therefore they represent ordinary timber with different lengths and widths.
Types and properties
Beams are distinguished by size, they are assigned numbers by which you can select the necessary characteristics individually for construction:
- Size “10” is the smallest by standards; it is used as a ceiling and strengthens moving elements in buildings. It can be installed as a guide structure for lifts, provided that they are small.
- “12” - the beam will be slightly larger and, accordingly, can withstand more pressure. Most often used as the basis of frames, installed in mechanisms and machines.
- Number “14” is more massive and helps to create more loaded floors; it can be installed in reinforced concrete structures, these are often installed in industrial construction.
- The “16” beam is distinguished by its strength and can already be a full-fledged support; it is installed not only to ensure the stability of gran beams, but also for the movement of workshop vehicles along rail lines.
- Beam “18” can be used specifically in the construction of buildings, creating reliable support. If you need to provide support for large mechanisms or provide stability for wide areas.
- "20" number is already included in the number large beams, it can be the basis for columns or frames for mechanical engineering.
- “25” is no longer used so often in the construction of houses, but it will sometimes be reliable for any lifting mechanisms, even large cranes.
- “30” number is also used as a basis for lifting, but unlike “25” it is made wider and longer, this provides higher resistance under heavy loads.
Aluminum and steel floors, their pros and cons.
Also often used in construction aluminum, or rather its alloys, it quite resistant to environmental influences, but does not have such stability under weight load. Compared to steel, they are lighter and thinner, but most often need to be thickened for additional strength. Both materials can be used in the construction of structures, depending on the volume of construction, since industrial production represents more extensive work with strong fortifications, but small buildings can be assembled from aluminum, it is economical and easy to use.
There is one important feature - metal when exposed high temperatures melts, literally melts, creating a homogeneous mass that cannot be restored, while aluminum, when heated, does not turn into a melted puddle, but, on the contrary, when the temperature decreases, it is restored to its normal appearance. Of course, not in every production environment has a temperature of 80 degrees, so there will be no deterioration with normal heating. From the outside chemical designations, iron has more noble compounds, and aluminum has not received recognition from chemists.
There is such a thing as the elastic modulus, it is responsible for the resistance of the material to regeneration after strong pressure, that is, if the action of the beam is aimed at bending, then it should not bend, so the greater the pressure, the higher the elastic modulus should be. Aluminum alloys have an elastic modulus of 70,000 MPa, which is three times less than that of iron. It is on this basis that a plan for the location of beams is constructed and their load-bearing capacity is calculated.
Shapes, thickness and height
The difference in shape and size is determined in accordance with the numbers of the manufactured beams; they can be either small and narrow with a solid shape, or massive I-beams that can easily support large working cranes. Individual manufacturing allows you to order a base for movable structures with specific characteristics and shapes. The most important thing is that the height must always be increased by 1.5 times, this will be used for shrinkage and other construction work.
Usage
The main purpose of metal floors is industrial engineering, it differs from civil special requirements. Most often, developers for these buildings already have ready plan, so there will be no problems with sketching the project, but for such an industry the material must have all certifications, because the structures will be used for mass gatherings of people or large factories, which are tested for strength by government agencies.
At the same time, complex metal structures are affordable for really large customers, their price is quite high, and in civil construction aluminum is most often used; although it is not so durable, there is no need to spend money on additional anti-corrosion treatment, and the material can withstand the standard load of a residential building.
Beam types
A beam is a solid element that works primarily on transverse bending and takes up the load located in the span, transferring it to the supports.
Split beams are most common in steel structures due to the certainty of their operation, as well as the ease of manufacture and installation.
The most suitable shape for bending work cross section beams, as is known, are I-beams. The possibility of using a channel profile is not excluded, if this is structurally convenient.
Beams can be rolled or composite. If possible, one should strive to use rolled beams as they are less labor-intensive. However, due to the limited range of rolled beams, powerful beams that absorb large moments have to be designed as composite welded or riveted ones.
Welded beams are made up of three sheets: one vertical, called the wall, and two horizontal, called, which are welded to the wall.
Riveted I-beams are made up of a vertical sheet - the wall - and waist corners, which are riveted to the wall. If it is necessary to use powerful riveted beams, then to increase the moment of resistance, horizontal sheets are riveted to the flanges of the corners.
Welded beams are more economical than riveted ones. Therefore, the latter have limited use, mainly in heavy structures, as well as in structures subject to high dynamic or vibration loads.
"Design of steel structures",
K.K. Mukhanov
Flat flooring metal sheet positioned and welded to the beam flanges. The thickness of the flooring is determined by calculation, most often depending on the accepted permissible deflection, since full use of the stresses in the sheet at a given deflection is not always possible. Therefore, the calculation of sheet flooring is carried out according to standard loads. The peculiarity of sheet flooring is that by its nature…
The general dimensions of the beam are its design span and section height. The design span of the beam l is the distance between the centers of the supporting parts; thus, the actual length of the beam lд is always slightly greater than the design span. The distance l0 is called the clear distance; it is usually determined by the operating conditions of the weapon and is justified by economic considerations. General dimensions of beams The section height h is assigned, ...
When designing beam structures, as a rule, it is necessary, depending on the purpose of the beams, to draw up a diagram of their location, outline the general dimensions and determine the load on the beams. If it is necessary to cover a certain area, the beams supporting the floor are usually placed in two directions. Such a structure, sometimes consisting of an entire system of intersecting beams, is called a beam cage. On a beam cage maybe...
Construction beams various types- these are logs, crossbars, purlins, crossbars, floor beams, roof battens, rafter legs. They carry the structure wooden flooring interfloor ceilings. Wooden ones are used on one- and two-story buildings, and reinforced concrete and metal ones are used on high-rise buildings. The basis of any roof is a beam frame that supports the weight of the entire roof.
Mauerlat
Mauerlat (carpenters call it matitsa) is the most thick timber, which lies parallel to the roof ridge along the axis of the wall. It is needed to distribute the loads from the rafters and the weight of the entire roof along the entire wall of the building, as well as on the internal supports. Do not lay or fasten closer than 5 cm from the outer plane of the wall. The mat is attached using thick wire, embedded into the wall masonry using studs, and if the wall is concrete, it is attached to the concrete with studs. If the house is one-story wooden, you can fasten it with ordinary nails.
Rafter-inclined beam
In most cases it is wooden beam section 7x15 cm. If the roof area is small, you can use 5x15 cm timber, and if the roof is covered clay tiles, then the beam is 8x20 cm. The rafters are located at a distance of 60 cm to 1 m from each other. Where there is a lot of snow, reduce the distance to 60 cm. If the roof slope is more than 45 degrees, you can increase the “step” to 1.2-1.4 meters. And further. When the roof is planned to be insulated, it is calculated in such a way as to eliminate cutting of insulation in order to save money.
Run
An additional support beam for supporting the rafters is located parallel to the matrix and the ridge. According to construction technology optimal distance between the purlin and the matrix (ridge and purlin) - 4-5 meters. If the rafters are extended to 6 meters, then the joint (bow) should be located above the purlin so that both ends of the rafters rest on it. Sometimes it happens that the rafters are composite (6+3) meters, and the width of the run is 4-5 meters. Then the joint is positioned in relation to the purlin in a checkerboard pattern.
The run itself is done like this. Exhibited support posts and the purlin is laid on them, and the rafter will rest on it. The purlin can also be supported on a wall longitudinal to it. Then horizontal expansion beams are laid between the upper purlins. Their purpose is to prevent the roof from folding inward. They are laid so as not to burst the purlin.
I-beams and rafters
The so-called I-beams and rafters have an even greater advantage. Their high specific strength allows them to be used in long spans. They are very straight, so there is no bending moment. Having precise dimensions, they are universal - suitable for the construction of roofs, ceilings and floors. Silent – eliminates creaking floors.
Stable - not subject to deformation. Profitable - save from 40 to 60 percent of materials and labor costs. Eco-friendly - they pollute the environment little. Convenient - can be processed and laid using ordinary carpentry tools. The I-beam is ideal for any roof frame, allowing you to increase the distance between purlins as it can withstand heavy loads.
Bent-laminated wooden beams
Bent-laminated wooden beams have also become very popular recently. They are used if it is necessary to increase the distances between runs. Lightness, reliability and strength are their main advantages. They are resistant to external environment, not subject to biological influence, easy to process. Among the disadvantages, it is worth noting the high cost and the lack of observations of the duration of their service, due to the fact that the material is quite new. It is also necessary to pay very close attention to the quality of such products, since failure to comply with the technology leads to drying out and deformation of the products.
Reinforced concrete beams
Reinforced concrete beams are now widely used in the construction frame structures, in particular, buildings with a height of more than one floor. Structurally, they ensure the ability of the entire structure to withstand large values of bending moments. Beam floors are arranged on spans more than 3 m wide and laid on walls at a distance of at least 130-150 cm from each other. Then they are connected to the reinforcement of the slab floor. The thickness of the support is at least 22 cm. They are widely used in the construction of retail, entertainment and industrial facilities.
Metal beams
Metal beams are the most durable and are mainly used in construction high-rise buildings. They serve as the main load-bearing structures and, due to their rigidity, transfer the load to places of support: columns, walls, partitions. Placed on top of metal beams Various types coatings After installing such a beam in the design position, it is secured in the supporting structures, formwork is arranged and reinforcement is installed. All tensile loads after pouring concrete are absorbed by this reinforcement.
Modern metal plants produce large quantities of rolled metal to strengthen construction projects. These products have different purposes, depending on their size and strength. The most durable type of rolled metal is the I-beam. It is used in the construction of very massive structures, since the beam can easily cope with heavy loads.
Features and purpose
I-beam- This metal product with a cross section in the shape of the letter “H”. It consists of two shelves and a wall connecting them. The name of this rolled metal product comes from the Latin word “taurus”. Translated into Russian, taurus means “bull”. That is, literally translated, this type of rolled metal is called a two-horned beam.
Steel is used to manufacture these products. As a rule, this is low-alloy or carbon steel, depending on the purpose of the future product. This metal is produced using the hot-rolled method.
I-beam is used in industrial and civil construction. With its help they reinforce:
- Roofs of varying degrees of complexity.
- Interfloor ceilings in apartment buildings.
- Columns of complex architectural objects.
- Steel trusses for civil and industrial buildings.
- Mine shafts.
- Railway carriages.
- Bridges and other structures built on a durable steel frame.
This beam is also used to create reliable crane trestles, masts and monorails.
Advantages and disadvantages
The main advantage of this rolled metal is its strength and reliability. These characteristics are related to the cross-sectional shape of the product. After all, the cross-section in the form of the letter “H” significantly increases the rigidity of the product. If we compare an I-beam with a conventional one, which has square shape in cross-section, the first one will be much stronger and tougher. The strength indicator of such products even exceeds similar characteristic at the channel.
High strength characteristics are associated with the distribution of mechanical load over metal structure. With a cross-section in the form of the letter “H,” the load is evenly distributed over the entire beam and is not concentrated at certain points. Therefore, when using this rolled metal, the risk of rapid wear and destruction is eliminated steel frame. Consequently, the I-beam can be used in the construction of very massive objects subject to huge loads. The main thing is to choose the right product sizes.
In addition to the strength characteristics, it is worth considering other advantages of using this rolled metal. The most important of them:
- Economical. Due to its rigidity, an I-beam reliably reinforces large objects without requiring the use of auxiliary reinforcement. If you had chosen a different type of reinforcing profile, you would have had to purchase it from more to ensure the structure's resistance to damage. In the case of an I-beam, this is not necessary. Consequently, you can save on rolled metal.
- Light weight. The cross-section in the shape of the letter “H” significantly reduces the weight of this rolled metal. At the same time, its strength characteristics increase noticeably in comparison with the same characteristics of more rigid square products.
- Resistance to bending and compression. Thanks to these advantages, the I-beam tolerates vibrations well and can be used in the construction of heavy bridges.
- Possibility of installation by welding. Welding elements steel structure significantly increases the speed of work and reduces the delivery time of the project.
- Constancy of geometric characteristics. Since the rigidity of the I-beam is determined by its shape, any changes in it would lead to a decrease in the strength of the frame and destruction of the building. This is excluded when using this rolled metal. After all, it does not deform even under too high loads.
- Ease and economy of transportation. To transport more massive rolled metal, you would have to rent several Vehicle. In the case of this product, the amount of transport can be reduced. After all, the specific shape of the I-beam facilitates compact installation, and its low weight allows you not to worry about overload.
Like any other rolled metal product, an I-beam has not only advantages, but also disadvantages. Let's consider the main ones:
- Poor fire resistance. If a fire breaks out at your facility, any delay in putting it out will have a detrimental effect on the strength of the structure. If the situation gets out of control, the building may even collapse.
- Weak resistance to corrosion. Carbon and low-alloy steel are susceptible to rust, so these materials must be treated with protective substances. And even after proper processing, the beam is not recommended for use in conditions of high humidity (for example, for the construction of underwater bridge supports).
- Impossibility of application on very large spans. In the absence of additional supports load-bearing capacity I-beams are noticeably reduced. You need to pay maximum attention to this feature of rolled metal when developing a project.
- Very low torsion resistance. This disadvantage observed in all products with an open cross-section. For example, the channel and corner have it. The beam's resistance to torsion is approximately 400 times lower than that of round pipe with the same cross-sectional area. If the frame of your future object will be subject to torsion, it is better to choose a different type of rolled metal for reinforcement.
Varieties
I-beams can be used for different purposes. Depending on the application, it has certain characteristics. For example, this rolled metal is produced with parallel or inclined shelves. In the first case we're talking about about ordinary rolled metal, and in the second about special ones. Products with parallel shelves are marked “U”, “W”, “D” or “K”. It means:
- “U” is a product with narrow shelves.
- "Sh" - rolled metal with wide shelves that can withstand heavy loads.
- “D” is an I-beam with middle shelves.
- "K" - products intended for the construction of columns. These beams are heavy and characterized by the highest degree of strength.
I-beams with inclined flanges also have different purposes, depending on the angle of inclination and cross-sectional area. It is marked with the letters “M” or “C”. Products marked “M” are intended for the construction of overhead tracks. The angle of inclination of its internal edges should not exceed 12%. Beams marked “C” are used to strengthen mine shafts. For these I-beams, the angle of inclination of the internal faces can reach 16%. Coefficients of 12% and 16% are the maximum values for the angle of this product. They cannot be exceeded during the production of rolled metal.
In addition to the width of the shelves and their angle of inclination, the I-beam is classified according to the degree of accuracy. This indicator indicates permissible deviations from dimensions during rolling (the table of dimensions and deviations is located in GOST 8239-89). The degree of accuracy is marked on the product with the letter “B” or “B”. If the beam is marked “B”, then it is a product with normal manufacturing precision. The letter "B" indicates increased accuracy. This product is suitable for complex tasks, requiring the absence of even the smallest errors. When manufacturing it, it is very important to comply with the permissible values of wall deflection, blunting of outer edges and curvature of the product itself.
IN state standard The following accuracy criteria are specified:
- The permissible wall deflection is no more than 0.15.
- The blunting of the outer edges is no more than 2.2 mm (for category “B”; for ordinary beams this indicator does not matter).
- The curvature of the product is no more than 0.2% of its length.
The accuracy of compliance with other characteristics (the height of the I-beam, as well as the width, thickness and skew of the shelf) depends on the category of the product (“B” or “B”) and its dimensions. All these coefficients are given in the table in GOST for rolled metal with normal and increased manufacturing accuracy.
Dimensions and weight
When manufacturing an I-beam, the requirements of GOST 8239-89 must be taken into account. These requirements regulate the dimensions of products and show their dependence on each other. For example, in a finished beam the following parameters are interrelated:
- cross-sectional area;
- radii of internal curvature;
- shelf thickness;
- angle of inclination of internal edges;
- product height;
- wall thickness;
- shelf width;
- radius of curvature of the shelf;
- product weight.
The value of these characteristics is not subject to change. For example, an I-beam marked “10” has a cross-sectional area of 12 square meters. cm. At the same time, its other characteristics should be equal to:
- radius of internal curvature = 7 mm;
- shelf thickness = 7.2 mm;
- product height = 100 mm;
- wall thickness = 4.5 mm;
- shelf width = 55 mm;
- shelf curvature radius = 2.5 mm;
- product weight = 9.46 kg (meaning the weight of a beam 1 meter long).
When manufacturing rolled metal of this type, all listed dimensions must be observed, since they are interconnected with each other. If at least one dimensional characteristic changes (for example, the length of the wall increases or the width of the flange decreases), the strength of the beam will noticeably decrease. This means that rolled metal cannot be used in construction work oh, because he will become too unreliable. Such a beam will break under any physical or seismic loads, which will lead to the destruction of a house, bridge or other object.
According to GOST 8239-89, an I-beam can have a cross-sectional area from 12 to 138 square meters. cm (depending on the size, the I-beam is marked with the numbers “10”, “12”, “14” ... “60”). The largest product from the state standard has the following characteristics:
- radius of internal curvature = 20 mm;
- average shelf thickness = 17.8 mm;
- I-beam height = 600 mm;
- thickness of the jumper between the shelves = 12 mm;
- width of each shelf = 190 mm;
- permissible radius of curvature of the shelf = 8 mm.
With such dimensional characteristics, the weight of the product should be 108 kg per meter. As a rule, beams are produced in lengths of 4-12 meters, and their length depends on the cross-sectional area of the rolled metal. How larger area, the longer the length. But there are also exceptions. For example, if a buyer needs beams of shorter length, he can order them directly from the manufacturer.
Also, when making to order, other characteristics can be changed. If in GOST 8239-89 the maximum cross-sectional area of an I-beam is specified as 138 sq. cm, this does not mean that you cannot obtain more massive products, if necessary. The state standard provides calculations within a limited range. Any other calculations are performed individually by engineers. That is, the customer contacts the manufacturer and leaves a request for the production of the products he needs. Next, the production process begins according to the following scheme:
- Calculations of dimensional characteristics are performed. When calculating these characteristics, their relationships with each other are observed, as in the products considered in GOST. Experts also determine the permissible error rate, depending on the degree of accuracy of the product. During the work, engineers take into account not only the dimensions of the beam, but also its coefficients such as moment of inertia, static half-section moment, moment of resistance and radius of gyration. Only if all these characteristics are observed can you obtain a high-quality, durable product.
- Drawings are being made. If you have your own drawings, you will not have to pay for this service. But keep in mind that the creation of such documentation requires very deep knowledge and experience in carrying out such work. Therefore, do not order a service from dubious specialists, focusing on low price. Remember that the strength of your I-beam and the entire structure that you are going to reinforce with beams made according to the drawings will depend on the correctness of the calculations.
- An I-beam is manufactured in the required quantity.
Where can I buy?
If you are interested in an I-beam, you can buy it here. This is the website of our company “MS” - a metal warehouse engaged in the sale of rolled products of any type. Here you will find products with heights from 100 to 691 mm. The catalog contains products with narrow, medium, normal and wide shelves. We can also offer you column and special beams. A list of available products and their characteristics are available for viewing on the website.
If you have not yet decided on the choice of rolled metal supplier, check out the advantages of our company. They attract new clients to us every day. Our main advantages:
- Cooperation with leading metal plants of the Russian Federation. We do not purchase goods from dubious persons, so we can confidently say that we sell high-quality rolled metal products.
- Big choice products. You will find an I-beam of any size in the catalog, therefore, you do not have to wait for its production. In addition, we have many other types of metal products, not just beams. If you professional builder, you know that when constructing a large object, I-beams alone will not be enough. You will have to buy fittings and other rental products. By collaborating with us, you will do this at the same time, without delaying construction work and without overpaying for delivery.
- Affordable prices. Since we take goods directly from metal plants, and not through intermediaries, we do not have to purchase them at a higher price. Accordingly, our clients receive rolled metal at the manufacturer’s price.
- Operational support. If you don't know which I-beam is suitable for your needs, ask our specialist for help. He will find you a product with optimal characteristics.
- Promotions and sales that allow you to save on your purchase.
- Useful additional services. We not only sell rolled products, but also weld and cut them.
To order an I-beam, check the cost of the product and wait for delivery. If you indicated an address in St. Petersburg, we will deliver the goods by our own car. In other cases, the products will be sent by a transport company suitable for you.
The photos used in the article are for illustration purposes and do not represent images of the company's products.
BEAM
1) the surface of the earth washed away by water in the form of a hollow. The lake has a fairly wide bottom and gentle slopes, covered with vegetation and often plowed in the upper part. B. is often found in steppe regions, where it is used to collect spring melt, storm and rain water. - 2) A log, beam (wooden or iron), supported by two or more supports and used to cover openings (windows, doors) or spans between walls. B. with a hanging end is called a cantilever.
Agricultural dictionary-reference book. - Moscow - Leningrad: State publishing house of collective farm and state farm literature "Selkhozgiz". Chief Editor: A. I. Gaister. 1934 .
Synonyms:See what "BALKA" is in other dictionaries:
Beam- – element flat floor; horizontal Basic structure buildings and structures: having a prismatic shape; resting on two or more points; used for covering rooms. [Terminological dictionary for construction on... ... Encyclopedia of terms, definitions and explanations building materials
- (German Balken log, crossbar). 1) a quadrangular log to which the floor or ceiling is attached. 2) a narrow, deep hollow with water at the bottom. Dictionary foreign words, included in the Russian language. Chudinov A.N., 1910. BEAM... ... Dictionary of foreign words of the Russian language
See tree... Dictionary of Russian synonyms and similar expressions. under. ed. N. Abramova, M.: Russian Dictionaries, 1999. beam, log, tree, timber, crossbar; beams, keelson, yaruga, ozda, crossbar, dry dol, I-beam, dol, console, girder,... ... Synonym dictionary
Dictionary Ushakova
1. BEAM1, beams, female. (German: Balken). 1. Tetrahedral log. 2. Horizontal beam serving as a connection between the walls (technical). Cross beam. Wooden, iron beam. 2. BEAM2, beams, female. (region). Long ravine, hollow (in the southern steppe... ... Ushakov's Explanatory Dictionary
BEAM. The word beam (German Balke, Dutch Balk, East Frisian Balke and Balk, Old Frisian Balk) penetrated into the Russian language through Pskov and Novgorod. In the Pskov and Novgorod languages it was known in the XIV-XV centuries. (cf. in 1 Pskov ... ... History of words
Beam- – horizontal load-bearing structure of buildings and structures, supported at two or more points. A beam that spans one span and has two supports is called a split beam. A beam spanning several spans and having several supports... ... Builder's Dictionary
Beam- BEAM, a term used in maritime affairs and shipbuilding, represents an iron beam or the simplest type of crane, used for lifting on board the ship those objects, the name of which is usually placed in front of this word. T., for example... Military encyclopedia
Balkar, a; R. pl. balkar... Russian word stress
Dahl's Explanatory Dictionary
Female, German beam, crossbar, matrix, log, placed at the ends on two walls, on pillars, on chairs under the house or for laying a runway, a floor, for lining a ceiling. | arch. by whom. cod liver. Cook fish soup on beams, on cod liver. Balchina women... Dahl's Explanatory Dictionary
