Encyclopedia of Fire Safety

Assigning links to farms. Vertical braces to provide rigidity to buildings. Frame structural diagram of frame buildings

Frame connections provide geometric immutability and stability of elements in the longitudinal direction, joint spatial work of frame structures, building rigidity and ease of installation and consist of two main systems: connections between columns and coating connections.

Connections between columns. The connections between the columns (Fig. 6.4) ensure the geometric immutability of the frame and its structure during operation and installation. bearing capacity in the longitudinal direction, they perceive and transmit to the foundation wind loads acting on the end of the building and the effects of longitudinal braking of overhead cranes, and also ensure the stability of columns from the plane of the transverse frames.

The column bracing system consists of over-crane single-plane V-shaped ties, located in the plane of the longitudinal axes of the building, and sub-crane two-plane cross-shaped ties, located in the planes of the column branches.

Crane connections in each row of columns are located closer to the middle of the building block to ensure freedom of temperature deformations in both directions and reduce thermal stresses in the frame elements. The number of ties (one or two along the length of the block) is determined by their load-bearing capacity, the length of the temperature compartment and the greatest distance L with from the end of the building (expansion joint) to the axis of the nearest vertical connection (see Table 6.1). If there are two vertical connections, the distance between them in the axes should not exceed 40 - 50 m.

Over-crane connections are installed at the outermost column spacings at the end of the building or temperature block, as well as in places where vertical connections are provided in the plane support posts roof trusses.

Intermediate columns (outside the bracing blocks) at the level of the trusses are braced with spacers.

At high altitude in the crane part of the column, it is advisable to install additional horizontal struts between the columns, reducing their estimated length from the plane of the frame (shown with a dotted line in Fig. 6.4).

Vertical connections columns are calculated for crane and wind loads W, based on the assumption of tensile work on one of the braces of the crane cross braces. At long length elements that perceive small forces, connections are taken to the utmost flexibility λ u = 200.

The tie elements are made from hot-rolled angles, the spacers are made from bent rectangular profiles.

Coverage connections. The coating bracing system consists of horizontal and vertical bracings that form rigid blocks at the ends of the building or temperature block and, if necessary, intermediate blocks along the length of the compartment (Fig. 6.5).

Horizontal connections in the plane of the lower chords of trusses are designed of two types. Ties of the first type consist of transverse and longitudinal braced trusses and braces (see Fig. 6.5, V G– at a step of 12 m). Ties of the second type consist of transverse braced trusses and braces (see Fig. 6.5, d– with a truss pitch of 6 m; see fig. 6.5, e– with a truss pitch of 12 m).


Rice. 6.4. Scheme of connections by columns


6.5. Coverage connections


Rice. 6.5(continuation)


Transverse braced trusses along the lower chords of trusses are provided at the ends of the building or temperature (seismic) compartment (see Fig. 6.5, d, e). An additional horizontal braced truss is also provided in the middle of a building or compartment with a length of more than 144 m in buildings erected in areas with an estimated outside air temperature of -40 o C and above, and with a building length of more than 120 m in buildings erected in areas with design temperature below –40 o C (see Fig. 6.5, V, G). This reduces the transverse movements of the truss chord, which arise due to the compliance of the connections. Transverse horizontal connections at the level of the lower chords of the trusses are perceived wind load to the end of the building, transmitted by the upper parts of the half-timbered posts, and together with the transverse horizontal connections along the upper chords of the trusses and the vertical connections between the trusses, they provide the spatial rigidity of the coating.

Longitudinal horizontal connections in the plane of the lower chords of trusses are provided along the outer rows of columns in buildings:

– with overhead support cranes of operating mode groups 7K and 8K, requiring the installation of galleries for passage along the crane tracks;

– with rafter trusses;

– with calculated seismicity 7, 8 and 9 points;

– with an elevation of the bottom of the trusses over 18 m, regardless of the lifting capacity of the cranes;

– in buildings with roofs on reinforced concrete slabs, equipped with overhead support cranes general purpose with a load capacity of over 50 tons with a truss spacing of 6 m and over 20 tons with a truss spacing of 12 m;

– in single-span buildings with a roof on a steel profiled deck, equipped with cranes with a lifting capacity of over 16 tons;

– with a truss pitch of 12 m using longitudinal half-timbering posts.

Transverse horizontal connections at the level of the upper chords of trusses are provided to ensure the stability of the chords from the plane of the trusses. Due to the lattice of cross braces along the upper chords of the trusses, the use of lattice girders is difficult and therefore transverse braces, as a rule, are not used. In this case, the decoupling of the trusses is ensured by a system of vertical connections between the trusses.

In buildings with roofs on reinforced concrete slabs, spacers are provided at the level of the upper chords of the trusses (see Fig. 6.5, A). In buildings with a roof on a steel profiled flooring, the spacers are located only in the space under the lanterns; the trusses are fastened to each other by purlins (see Fig. 6.5, b); with a calculated seismicity of 7, 8 and 9 points, transverse braced trusses or stiffening diaphragms are also provided, installed at the ends of the seismic compartment (see Fig. 6.5, and– with a truss pitch of 6 m; see fig. 6.5, To- with a truss pitch of 12 m), and additionally at least one for a compartment length of more than 96 m in buildings with a calculated seismicity of 7 points and with a compartment length of more than 60 m in buildings with a calculated seismicity of 8 and 9 points.

In stiffening diaphragms, the profiled flooring, in addition to the main functions of enclosing structures, performs the function of horizontal connections along the upper chords of the trusses. Transverse stiffening diaphragms and horizontal braced trusses absorb longitudinal design horizontal loads from the coating.

In buildings with a lantern, if an intermediate stiffening diaphragm is installed, the lantern above the diaphragm must be interrupted. Rigidity diaphragms are made from profiled flooring grades H60-845-0.9 or H75-750-0.9 in accordance with GOST 24045-94 with reinforced fastening to the purlins.

Rafter trusses that are not directly adjacent to the transverse braces are secured in the plane of location of these braces with spacers and braces. Spacers provide the necessary lateral rigidity of the trusses during installation (ultimate flexibility of the upper chord of the truss from its plane during installation λ u= 220). Stretches are provided to reduce the flexibility of the lower belt in order to prevent vibration and accidental bending during transportation. The maximum flexibility of the lower chord from the plane of the truss is assumed to be: λ u= 400 – with static load and λ u= 250 – with cranes operating in 7K and 8K operating modes or when exposed to dynamic loads applied directly to the truss.

For horizontal bracing, a triangular lattice braced truss is usually adopted. When the pitch of the trusses is 12 m, the bracing racks of the braced trusses are designed with a sufficiently large vertical stiffness(usually from bent rectangular profiles) to support long diagonal braces on them, made from angles with insignificant vertical rigidity.

Vertical connections between trusses are provided along the length of the building or temperature compartment in the locations of transverse braced trusses along the lower chords of the trusses. In buildings with a calculated seismicity of 7, 8 and 9 points and a roof on a steel profiled flooring along rows of columns, vertical braces are installed in the locations of braced trusses or stiffening diaphragms along the upper chords of the trusses.

The main purpose of the vertical braces is to ensure the design position of the trusses during installation and to increase their lateral rigidity. Usually one or two vertical connections are installed along the width of the span (every 12 - 15 m).

When the lower assembly of the trusses is supported on the column head from above, the vertical connections are also located in the plane of the truss support posts. When the trusses are adjacent to the side of the column, these connections are located in a plane aligned with the plane of the vertical connections of the crane part of the column.

In the coatings of buildings operated in climatic regions with a design temperature below –40 o C, it is necessary, as a rule, to provide (in addition to the usually used braces) vertical braces located in the middle of each span along the entire building.

In the presence of hard drive On the roof, at the level of the upper chords of the trusses, inventory removable connections should be provided to verify the design position of the structures and ensure their stability during the installation process.


To ensure the spatial stability of metal structures, special steel elements are used - vertical connections between columns. The production association "Remstroymash" offers metal structures self-made for various manufacturing and construction enterprises.

The company's assortment includes:

  • Rods.
  • Beams.
  • Farms.
  • Frames and other connection systems.

The main purpose of connections of metal structures

With the help of the lungs structural elements spatial systems are formed that have unique properties:

  • bending and lateral torsional rigidity;
  • resistance against wind loads and inertial influences.

When assembled, the connecting systems perform the listed functions aimed at increasing resistance against external influences. Wind connections of metal structures give the finished structures additional sail stability during operation. The spatial rigidity and stability of buildings, columns, bridges, trusses, etc. is ensured thanks to connections installed in horizontal planes in the form of upper and lower chords.

At the same time, special connections of vertical metal structures - diaphragms - are installed at the ends and in the spaces between spans. The resulting system of connections provides the required spatial rigidity of the finished structure.


Transverse connections of spans
a - design of the main connection points; b - cross-link diagram

Types of connections of metal structures

Products differ in manufacturing and assembly methods:

  • Welded products.
  • Prefabricated (bolt, screw).
  • Riveted.
  • Combined.

The materials used for the manufacture of connecting metal structures are ferrous and stainless steel. Thanks to the unique technical specifications, stainless steel products do not require additional processing against corrosion.

Vertical connection diagrams:
A cross; B two-tier cross, C - diagonal inclined, D - multi-tiered diagonal inclined

Examples of connections



The metal frame, as many people know, is the main structure of frame-panel buildings. It consists of a wide variety of structural elements: beams, trusses, half-timbers, struts and others. In this review we will look at such structural elements as connections.
Metal bonds are intended for the overall stability of the metal frame in the longitudinal and transverse directions, so their importance is quite high. They counteract the main horizontal load on the frame coming from the wind. The greatest effect here is noticeable when using anti-corrosion materials. What factors and materials need to be taken into account? Siding series "Mitten" and all types of siding from the manufacturer. Fiberglass septic tanks are also important for sewerage in the residential sector or country house, where repairs and improvement are provided. Thanks to them, positive results can be achieved. And, of course, foundation work preceded by groundwork is important. Which ones should I highlight? Drilling water wells, water treatment and water supply all year round- all this is relevant for industrial building. However, any real estate objects are interesting. The fashion for real estate allows you to buy an apartment in a new building under convenient conditions. What is the reason for this? Huge selection. New buildings in Moscow from developers. No commission.
There are three types of connections in a metal frame: cross, corner and portal. Today, such products are easy to purchase not only from industrial manufacturing enterprises; equipment of the Eurostandard brand stands out especially. These products are also available on the Internet. According to experts, the cost of creating an online construction store is low, so buying metal products there is very profitable. An energy audit will help to estimate the cost, regardless of the calculations.
Cross ties represent the classic and simplest option, when the elements of the ties intersect and are attached to each other in the middle of the length. Such technologies, as professionals note, are often used during installation utility rooms and structures. What can be noted? Cabins and containers with dry closets. Toilet cabins, according to experts, have a wide range. Currently they are very popular. As practice shows, it is only necessary here. Durable installation metal doors with the existing modernization in 4 hours it will be an excellent technological solution for these structures. This is also relevant for the facade. Hurry up to buy façade thermal panels with clinker and light tiles at a special price! Order a car for this. Forward! A car loan is almost like buying a car. Legal advice is also appropriate here.
Corner braces are usually used for small spans and are arranged in a row of several parts. They are smaller in height than cross connections. Of course, it is recommended to use here insulating materials. Today this is not a problem. Just look at the advertising applications of some companies that demand to buy “technological” insulation on favorable terms - only with the best filling! And this, according to experts, the right approach to construction.
Portal connections are the largest in terms of working area. They have a U-shaped appearance and find their application in those spans metal frame where window or door openings or furniture elements are provided. Find out all the secrets of furniture makers: custom-made kitchens with custom-made furniture. There is also an excellent renovation of a one-room and complex apartment to order.
If we talk about what is used for making connections, then most often it is a corner or a bent square or rectangular profile, less often a channel or an I-beam.
Of the existing frames for connections, the most applicable bolted connections, as technologically and structurally the most efficient and convenient for installation.
In accordance with the rules of the metal frame, the connections are located both in the longitudinal direction of the structure being designed, and in the transverse direction - along its ends. In this case we are talking about vertical metal connections. They are used in many systems, even in everyday life. What can you take as an example? Electrical system steam generators and air conditioners - this is a unique combination. This is a very popular modern technological device.
Sometimes the structural design of a metal frame requires the use of horizontal connections. For the most part, this occurs on a large scale, with long spans and significant heights for typical columns. Horizontal connections here are usually of the cross type and are located in several modules in a row in longitudinal spans between trusses, which are always designed for large-sized metal frames.
As for the designations of metal connections in a metal frame, a thick dash-dotted line is usually used for them.

Connections between columns.

The system of connections between the columns ensures during operation and installation the geometric immutability of the frame and its load-bearing capacity in the longitudinal direction, as well as the stability of the columns from the plane of the transverse frames.

The connections that form HDD, are located in the middle of the building or temperature compartment, taking into account the possibility of columns moving due to thermal deformations of the longitudinal elements.

If you install connections (hard drives) at the ends of the building, then large thermal forces F t arise in all longitudinal elements (crane structures, rafter trusses, bracing struts)

When the length of a building or temperature block is more than 120 m, two systems of tie blocks are usually installed between the columns.

Limit dimensions between vertical connections in meters

Dimensions in brackets are given for buildings operated at design outdoor temperatures t= –40° ¸ –65 °С.

Most simple circuit cross braces, it is used for column spacing up to 12 m. Rational angle of inclination of the braces, therefore, when not big step, but at high column heights, two cross connections are installed along the height of the lower part of the column.

In the same cases, sometimes additional decoupling of columns from the plane of the frame with spacers is designed.

Vertical connections are installed along all rows of the building. With a large pitch of columns in the middle rows, and also in order not to interfere with the transfer of products from bay to bay, connections of portal and semi-portal schemes are designed.

The vertical connections between the columns receive forces from the wind W 1 and W 2 acting on the end of the building and the longitudinal braking of the cranes T pr.

Elements of cross and portal connections work in tension. Due to their high flexibility, compressed rods are excluded from work and are not taken into account in the calculation. The flexibility of tensile tie elements located below the level of crane beams should not exceed 300 for ordinary buildings and 200 for buildings with “special” crane operating modes; for connections above crane beams - 400 and 300, respectively.



Coverage connections.

Connections along the roof (tent) structures or connections between the trusses create the overall spatial rigidity of the frame and provide: stability of the compressed chords of the trusses from their plane, redistribution of local crane loads applied to one of the frames to adjacent frames; ease of installation; specified frame geometry; perception and transmission of some loads to the columns.

Coverage connections are located:

1) in the plane of the upper chords of the trusses - longitudinal elements between them;

2) in the plane of the lower chords of trusses - transverse and longitudinal braced trusses, as well as sometimes longitudinal braces between transverse braced trusses;

3) vertical connections between trusses;

4) communications via lanterns.

Connections in the plane of the upper chords of the trusses.

The elements of the upper chord of the trusses are compressed, so it is necessary to ensure their stability from the plane of the trusses.

Reinforced concrete roofing slabs and purlins can be considered as supports that prevent the upper nodes from moving out of the plane of the truss, provided that they are secured against longitudinal movements by connections located in the plane of the roof. It is advisable to place such ties (transverse trusses) at the ends of the workshop so that they, together with transverse trusses along the lower chords and vertical ties between the trusses, create a spatial block that ensures the rigidity of the coating.

If the building or temperature block is longer, intermediate transverse braced trusses are installed, the distance between which should not exceed 60 m.

To ensure the stability of the upper chord of the truss from its plane within the lantern, where there is no roofing, special spacers are provided, and trusses are required in the ridge assembly. During the installation process (before installing the covering slabs or purlins), the flexibility of the upper chord from the plane of the truss should be no more than 220. Therefore, if the ridge spacer does not provide this condition, an additional spacer is placed between it and the spacer on the truss support (in the plane of the columns).

Connections in the plane of the lower chords of trusses

In buildings with overhead cranes, it is necessary to ensure horizontal rigidity of the frame both across and along the building.

When operating overhead cranes, forces arise that cause transverse and longitudinal deformations of the workshop frame.

If the lateral rigidity of the frame is insufficient, the cranes may jam during movement and normal operation will be disrupted. Excessive frame vibrations create unfavourable conditions for the operation of cranes and the safety of enclosing structures. Therefore, in single-span buildings of great height (H>18 m), in buildings with overhead cranes Q>100 kN, with cranes of heavy and very heavy operating modes with any load capacity, a system of connections along the lower chords of the trusses is required.

Horizontal forces F from overhead cranes act transversely on one flat frame or two or three adjacent ones.

Longitudinal braced trusses provide working together systems of flat frames, as a result of which the transverse deformations of the frame from the action of concentrated force are significantly reduced.

The end frame posts transmit the wind load F W to the nodes of the transverse braced truss.

To avoid vibration of the lower chord of the truss due to the dynamic impact of overhead cranes, the flexibility of the stretched part of the lower chord from the plane of the frame is limited: for cranes with a number of loading cycles of 2 × 10 6 or more - by a value of 250, for other buildings - by a value of 400. To reduce the length of the stretched part of the lower In some cases, belts are equipped with stretchers that secure the lower belt in the lateral direction.

Vertical connections between farms.

These ties connect the trusses together and prevent them from tipping over. They are installed, as a rule, in axes where connections are established along the lower and upper chords of the trusses, forming together with them a rigid block.

In buildings with suspended transport, vertical connections contribute to the redistribution between the trusses of the crane load applied directly to the covering structures. In these cases, as well as to the trusses, an electric crane is attached - beams of significant lifting capacity; vertical connections between the trusses are located in the suspension planes continuously along the entire length of the building.

The structural diagram of the connections depends mainly on the pitch of the trusses.

Ties along the upper chords of trusses

Ties along the lower chords of trusses

For horizontal connections with a truss pitch of 6 m, a cross lattice can be used, the braces of which work only in tension (Fig. a).

Recently, braced trusses with a triangular lattice have been mainly used (Fig. b). Here the braces work in both tension and compression, so it is advisable to design them from pipes or bent profiles, allowing to reduce metal consumption by 30-40%.

With a pitch of trusses of 12 m, the diagonal elements of the ties, even those working only in tension, turn out to be too heavy. Therefore, the bracing system is designed so that the longest element is no more than 12 m, and the diagonals are supported by this element (Fig. c, d).

It is possible to ensure fastening of longitudinal braces without a grid of braces along the upper chord of the trusses, which does not make it possible to use through purlins. In this case, the rigid block includes covering elements (purlins, panels), trusses and often located vertical braces (Fig. e). This solution is currently standard. The connection elements of the tent (covering) are calculated, as a rule, based on flexibility. The maximum flexibility for compressed elements of these connections is 200, for stretched elements - 400, (for cranes with a number of cycles of 2 × 10 6 or more - 300).

A system of structural elements that serve to support the wall fence and absorb wind loads called half-timbered.

Half-timbered structures are installed for loaded walls, as well as for interior walls and partitions.

With self-supporting walls, as well as with panel walls with panel lengths equal to the column spacing, there is no need for half-timbered structures.

With a pitch of external columns of 12 m and wall panels 6 m long intermediate half-timbered posts are installed.

Half-timbering installed in the plane of the longitudinal walls of a building is called longitudinal half-timbering. A half-timbering installed in the plane of the walls at the end of a building is called an end half-timbering.

The end timber frame consists of vertical posts, which are installed every 6 or 12 m. The upper ends of the posts in the horizontal direction rest on a transverse braced truss at the level of the lower chords of the trusses.

In order not to prevent the deflection of trusses from temporary loads, the support of the half-timbered posts is carried out using sheet hinges, which are a thin sheet t = (8 10 mm) with a width of 150 200 mm, which easily bends in the vertical direction without interfering with the deflection of the truss; in the horizontal direction it transmits force. Crossbars are attached to the half-timbered posts for window openings; when the height of the racks is high, spacers are placed in the plane of the end wall to reduce their free length.

Walls made of bricks or concrete blocks are designed to be self-supporting, i.e. taking up their entire weight, and only the lateral load from the wind is transferred by the wall to the column or half-timbered post.

Walls made of large-panel reinforced concrete slabs are installed (hung) on ​​tables of columns or half-timbered posts (one table every 3 - 5 slabs in height). In this case, the half-timbered post works in eccentric compression.

The metal frame consists of many load-bearing elements(truss, frame, columns, beams, crossbars), which must be “connected” with each other to maintain the stability of the compressed elements, rigidity and geometric immutability of the structure of the entire building. To connect structural elements of the frame they are used metal connections. They perceive the main longitudinal and transverse loads and transfer them to the foundation. Metal ties also distribute loads evenly between the trusses and frame frames to maintain overall stability. Their important purpose is to counteract horizontal loads, i.e. wind loads.

The Saratov Reservoir Plant produces connections from hot-rolled sectional angles, bent angles, bent profile pipes, hot-rolled profile pipes, round pipes, hot-rolled and bent channels and I-beams. The total mass of metal used should be approximately 10% of total mass metal structures of the building.

The main elements that connect the links are trusses and columns.

Metal column connections

Column braces provide lateral stability metal structure building and its spatial immutability. The connections between columns and racks are vertical metal structures and are structurally struts or disks that form a system of longitudinal frames. The purpose of hard drives is to attach columns to the foundation of a building. Spacers connect the columns in a horizontal plane. Spacers are longitudinal beam elements, e.g. interfloor ceilings, crane beams.

Within the column connections there are connections of the upper tier and connections of the lower tier of columns. The connections of the upper tier are located above the crane beams, the connections of the lower tier, respectively, below the beams. Main functional purposes loads of two tiers are the ability to transfer wind load to the end of the building from the upper tier through the transverse connections of the lower tier to the crane beams. The upper and lower braces also help keep the structure from tipping over during installation. The connections of the lower tier also transfer the loads from the longitudinal braking of the cranes to the crane beams, which ensures the stability of the crane part of the columns. Basically, in the process of erecting metal structures of a building, the connections of the lower tiers are used.

Scheme of vertical connections between columns

Metal truss connections

To impart spatial rigidity to the structure of a building or structure metal trusses are also connected by bonds. A truss connection is a spatial block with adjacent trusses attached to it. Adjacent trusses along the upper and lower chords are connected horizontal truss connections, and along the grille posts - vertical truss connections.

Horizontal connections of trusses along the lower and upper chords

Horizontal truss connections are also longitudinal and transverse.

The lower chords of the trusses are connected by transverse and longitudinal horizontal connections: the first fix the vertical connections and braces, thereby reducing the level of vibration of the truss belts; the latter serve as supports for the upper ends of the posts of the longitudinal half-timbering and evenly distribute the loads on adjacent frames.

The upper chords of the trusses are connected by horizontal transverse links in the form of struts or girders to maintain the designed position of the trusses. Cross braces connect the upper chords of the truss into unified system and become the “closing edge”. The spacers prevent the trusses from shifting, and the transverse horizontal trusses/braces prevent the spacers from shifting.

Vertical truss connections are necessary during the construction of a building or structure. They are often called installation connections. Vertical connections help maintain the stability of trusses due to the displacement of their center of gravity above the supports. Together with intermediate trusses, they form a spatially rigid block at the ends of the building. Structurally, vertical truss connections are disks consisting of struts and trusses, which are located between the posts of trusses along the entire length of the building.

Vertical connections of columns and trusses

Metal bracing structures of steel frame

By design, metal connections can also be:

    cross connections, when elements of connections intersect and connect together in the middle

    corner connections, which are arranged in several parts in a row; mainly used for the construction of short-span frames

    portal connections for frames U-shaped(with openings) have large area surfaces

The main type of connection of metal connections is bolted, since this type of fastening is most effective, reliable and convenient during the installation process.

Specialists of the Saratov Reservoir Plant will design and manufacture metal connections from any profile in accordance with the mechanical requirements for physical and chemical properties material depending on technical and operational conditions.

The reliability, stability and rigidity of the metal frame of your building or structure largely depends on high quality workmanship metal bonds.

How to order the production of metal connections at the Saratov Reservoir Plant?

To calculate the cost of our metal structures, you can:

  • contact us by phone 8-800-555-9480
  • write to email technical requirements to metal structures
  • use the form " ", provide contact information, and our specialist will contact you

The Plant’s specialists offer comprehensive services:

  • engineering surveys at the operation site
  • design of oil and gas complex facilities
  • production and installation of various metal structures

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