Truss support unit made from angles. Calculation and design of truss nodes from paired corners
MANAGEMENT
BY DESIGN
WELDED TRUSSES
FROM SINGLE CORNERS
When compiling the manual, the requirements of the SNiP chapter on the design standards of steel structures were taken into account.
The guide is intended for organizations designing steel structures.
INTRODUCTION
This Guide applies to the design of welded metal trusses from single angles for coatings and floors of industrial and civil buildings, transport overpasses and other similar structures.
Trusses made from single angles, compared to conventional trusses from paired angles, are more corrosion resistant due to the open sections of the elements, which are easily accessible for painting and inspection. The labor intensity of manufacturing these trusses is less than the labor intensity of manufacturing conventional trusses by 30 - 40% due to the fact that they are formed from a smaller number of parts. The weight of trusses from single corners is the same as that of ordinary trusses, or slightly less (5 - 7%).
The appendix to the Manual provides an example of solving a truss with a span of 24 m from single angles with parallel chords, which provides a general view and sketches of the truss nodes.
The manual was developed by the Department of Strength and New Forms of Metal Structures of the TsNIISK named after. V.A. Kucherenko (Doctor of Technical Sciences, Prof. V.A. Baldin, Candidate of Technical Sciences G.G. Golenko).
1. GENERAL PROVISIONS
1.1. Single corner trusses are trusses in which all the elements of the chords and lattice are formed from single corners, one flange located in the plane of the truss, and the other from its plane (see appendix).
1.2. In trusses made from single corners, the chords and saddle brace should be designed from steel class C 46/33 with design resistance R= 2900 kgf/cm2. The remaining truss rods, nodal gussets and linings should be designed from steel class C 38/23.
Note. In some cases, with truss spans of 18 - 24 m and light loads, it is rational to design all truss elements from steel class C 38/23.
2. CALCULATION OF ELEMENTS OF TRUSS FROM SINGLE CORNERS
2.1. Calculation of truss elements from single angles is carried out in accordance with the instructions of chapter SNiP II-B.3-72 “Steel structures. Design Standards" and this Guide.
a) if the rods are attached only at the ends - minimal;
b) in the presence of intermediate fastening (spacers, trusses, connections, etc.), which predetermines the direction of bulging of the angle in a plane parallel to one of the flanges - relative to the axis parallel to the second flange of the angle.
2.3. Compressed elements of trusses: belt, posts, braces, including the support brace, if it does not have intermediate fastenings, are checked for stability as centrally compressed rods. When determining the appropriate flexibility, the design lengths and radii of gyration are taken in accordance with paragraphs of this Manual.
W x(max) - maximum moment of resistance relative to the axis X- X(cm. ).
Designation of the axes of an isosceles angle
When checking for stability between fastening points in the plane of the truss, such braces are calculated as centrally compressed rods. In this case, the minimum radius of gyration is introduced.
2.5. Working conditions factor m when calculating the main compressed elements of the truss lattice, when they are attached to a node by one flange (see), it is taken m = 0,8.
2.6. In the case of a uniformly distributed load located directly along the upper chord of the truss, secured against displacement from the plane of the truss, for example, with a steel profiled deck laid overlapping on the upper chord and attached to it with self-tapping bolts, the upper chord must be checked for strength in the section near the node, and also for stability as an eccentrically compressed element, the bending of which occurs in the plane of the truss, according to the following formulas: when checking the strength in the section near the node
|
|
when checking stability
|
N ≤ φ vn FR |
Where N- longitudinal force;
M- bending moment near the node, taken equal to:
R- design resistance;
W x(min) - minimum value of the moment of resistance relative to the axis X - X(see picture) for the corner of the compressed belt;
With- coefficient equal to 1.2;
φ vn - coefficient determined in the same way as in paragraph of this Manual, but the eccentricity of the application of force
3. DESIGN INSTRUCTIONS
3.1. Truss elements are designed, as a rule, from equilateral angles, but unequal angles can also be used, located with their large flange from the plane of the truss, when the free length from the plane of the truss of the compressed elements is greater than in its plane.
3.2. The vertical planes passing through the center of gravity of the corners of the support brace and the upper chord should not be spaced from each other by more than the thickness of the flange of the thickest corner.
3.3. At the truss nodes, the corners of the support brace and lattice elements are welded to the internal planes of the flanges of the belt corners.
If the size of these shelves is not sufficient for attaching the lattice elements, gussets are welded to them end-to-end (Fig. - appendices).
3.4. The support unit of the truss should be designed in such a way that the center of the support rib is aligned with the axis of the truss (Fig. and appendices), the distance of which from the butt of the upper chord is determined in accordance with paragraphs of this Manual.
3.5. The axis of the truss, aligned with the alignment axis of the row, is taken to be distant from the butt of the upper chord, depending on the size of the flange, located normal to the plane of the truss at a distance:
for an isosceles angle:
for an unequal corner:
3.6. In a truss with a downward (stretched) support brace, the connection point between the support brace and the lower chord (application figure) must be secured against displacement from the plane of the truss.
3.7. The rules for establishing connections in coverings with trusses from single corners are the same as for coverings with trusses from paired corners.
3.8. To attach purlins and connections, strips are welded to the upper chord (see Appendix). The thickness of the strip is assumed to be δ = 12 mm.
4. INSTRUCTIONS FOR PRODUCTION AND INSTALLATION
4.1. Assembly, welding and installation of trusses are carried out in accordance with the instructions in the chapter on the rules for the manufacture, installation and acceptance of metal structures of SNiP and taking into account paragraphs of this Manual.
In trusses made of paired corners made by a brand, the nodes are designed on gussets that are inserted between the corners. The lattice rods are attached to the gusset using flank seams (Fig. 9.17). The force in the element is distributed between the seams along the butt and leg of the angle in inverse proportion to their distances to the axis of the rod. The difference in seam areas is adjusted by the thickness and length of the seams. The ends of the flank seams are brought out to the ends of the rod by 20 mm to reduce stress concentration. The gussets are attached to the belt with continuous seams and
they are released beyond the edge of the waist corners by 10-15 mm.
The seams attaching the gusset to the belt, in the absence of nodal loads, are calculated on the difference in forces in adjacent panels of the belt (Fig. 9.16, V)
Where purlins or roofing slabs rest on the upper belt
(Fig.9.17, V,G) the gussets do not reach the edges of the waist corners by 10-15mm.
To attach the purlins, a corner with holes for bolts is welded to the upper chord of the truss (Fig. 9.17, V). At points of support large panel slabs The upper chord of the truss is reinforced with mm overlays if the thickness of the chord corners is less than 10 mm with a truss pitch of 6 m and less than 14 mm with a truss pitch of 12 m.
To avoid weakening the section of the upper chord, do not weld the linings with transverse seams.
When calculating knots, they are usually set to the value “” and the required seam length is determined.
Truss gussets with a triangular lattice are designed with a rectangular cross-section, and with a diagonal lattice - in the form of a rectangular trapezoid.
To ensure smooth transfer of force and reduce stress concentration, the angle between the edge of the gusset and the grid element must be at least 15 0 (Fig. 9.17, V).
The joints of the belts must be covered with overlays made of
sheets (Fig. 9.18) or corner. To attach the corner trim
it is necessary to cut off the edge and flange of the corner. The reduction in its cross-sectional area is compensated by the gusset.
When installing sheet overlays, the gusset comes into play. The center of gravity of the section at the joint does not coincide with the center of gravity of the belt section, and it works in eccentric tension (or compression), so the belt joint
taken outside the unit to facilitate the work of the gussets.
To ensure that the corners work together, they are connected with gaskets. The distance between gaskets should be no more than 40 i for compressed and 80 i for tension elements, where i- radius of inertia of one corner relative to an axis parallel to the gasket. In this case, at least two gaskets are placed in the compressed elements.
Solutions for the enlarged truss unit when delivered from individual sending elements are shown in Fig. 9.19.
The design of support units depends on the type of support (metal or reinforced concrete columns, brick walls etc.) and the method of coupling (rigid or articulated).
When the trusses are freely supported on the underlying structure, a possible solution for the support unit is shown in Fig. 9.20. Truss Pressure Through Slab
a – centering of the rods; b – unit with a diagonal lattice; c – attaching purlins; d – attaching large-panel slabs
transmitted to the support. The area of the slab is determined by the load-bearing capacity
support material.
where is the calculated compressive resistance of the support material.
The slab bends due to the resistance of the support material in the same way as the column base slab (see Chapter 8).
The pressure of the truss is transmitted to the base plate through the gusset and the support post, which form a rigid cross-section support. The axes of the belt and support brace are centered on the axis of the support post.
The seams welding the gusset and support post to the slab are designed to
ground reaction.
 |
| Rice. 9.18. Factory joint of the belt with a change in section |
Holes for anchors are made in the base plate. The diameter of the holes is made 2-2.5 times larger than the diameter of the anchors, and the washers of the anchor bolts are welded to the slab.
For ease of welding and installation of the unit, the distance between the lower chord and
the base plate is taken to be more than 150mm.
We similarly construct the support unit when supporting the truss at the level of the upper chord (Fig. 9.19.b).
End of work -
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Steel Material Standard resistance of weld metal
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Determination of the design length of the rods
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Ultimate flexibility of rods
Structural elements must be designed from rigid rods. Flexibility is especially important.”
Selection of sections of truss elements
In trusses made of rolled and bent profiles, for the convenience of metal assembly, no more than 5-6 profile calibers are accepted. To ensure the quality of welding and increase corrosion resistance
Selection of sections of compressed elements
The limiting state of compressed truss elements is determined by their stability, therefore the load-bearing capacity of the elements is checked using the formula
Selection of the section of tensile elements
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Selection of rod cross-sections for maximum flexibility
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V): V),
44.49. Design of heavy truss units.
In heavy trusses, it is necessary to more strictly maintain the centering of the rods in the nodes along the axes passing through the centers of gravity, since even with small eccentricities, large forces in the rods cause significant moments that must be taken into account when calculating the trusses. Installation connections in welded trusses, especially when the trusses operate under dynamic loads, are often designed with high-strength bolts (Fig. 9.30, A), which greatly simplifies installation work and ensures high reliability of the design. Due to the presence of a node in the center increased voltages It is useful to have a thickening of the belt within the knot. This thickening is obtained in knots on rivets or bolts thanks to knotted gussets and overlays (see Fig. 9.30); 
45. Truss nodes from paired corners Design and calculation. Support node.
In trusses with rods made of two corners, assembled by a brand, the nodes are designed on packages that are inserted between the corners. The lattice rods are attached to the gusset using flank seams. The seams attaching the gusset to the belt are calculated on the difference in forces in adjacent panels of the belt (Fig. 9.18, V): To attach the purlins, a corner with holes for bolts is welded to the upper chord of the trusses (Fig. 9.18, V),
46. Truss nodes from paired angles Design and calculation. Ridge knot.
In trusses with rods made of two corners, assembled by a brand, the nodes are designed on packages that are inserted between the corners. The lattice rods are attached to the gusset using flank seams. The seams attaching the gusset to the belt are calculated on the difference in forces in adjacent panels of the belt (Fig. 9.18, V): To attach the purlins, a corner with holes for bolts is welded to the upper chord of the trusses (Fig. 9.18, V),
47. Truss units from the brand. Design and calculation. Node for changing the section of the belt
. I-beams with parallel flange edges are obtained by longitudinally unraveling wide-flange I-beams. Brands are used in truss belts; the lattice is made of paired or single hot-rolled or cold-formed corners. Compared to trusses with rods made from paired corners, trusses with belts made from T-bars are 10-12°/o more economical in terms of metal weight, 15-20% less in labor intensity, and 10-15% more cost-effective. Savings are achieved by reducing the number of parts, gusset sizes and lengths welds. With lattice rods made of paired corners and with a typical truss lattice design, as a rule, it is necessary to have nodal widening in order to obtain the required length of welds (Fig. 9.22, A). 
48. Design of truss units from bent profiles. Trusses made of bent-welded closed profiles are designed with non-facing units and with non-running roof support (Fig. 9.27) -. To simplify the design of nodes, truss diagrams should be adopted with a sparse lattice, in which no more than two lattice elements are adjacent to the chords at the nodes.
To include a compressed rod in the calculation of its full cross-section, it is necessary to satisfy the condition to ensure the stability of the wall: The wall thickness of the truss rods is recommended to be at least 3 mm. Profiles of the same cross-sectional dimensions, differing in wall thickness by less than 2 mm, should not be used in one truss. To ensure the density of the weld sections on the side of the acute angle, the angles at which the braces join the chord must be at least 30°. To avoid double cutting of the ends of the bars, avoid crossing the lattice bars at the nodes. 
50.Frame of a one-story industrial building. Layout of columns in plan. Frame, i.e. a complex of load-bearing structures that receives and transfers to the foundations loads from the weight of enclosing structures, technological equipment, atmospheric loads and influences, loads from intra-shop transport (bridge, overhead, jib cranes), temperature technological influences, etc. , can be made of reinforced concrete, mixed (i.e., part of the structures are reinforced concrete, part is steel) and steel. The choice of frame material is an important technical and economic task. The structural designs of frames are quite diverse. In frames with equal column spacing along all rows, the simplest structural design is transverse frames on which crane structures, as well as covering panels or purlins, rest (Fig. 10.2, a, b)
51Vertical connections in the frame of an industrial building. Basic diagrams of the installation site . 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 (while accepting some loads), as well as the stability of the columns from the plane of the transverse frames. Upper vertical braces should be placed not only in the end panels of the building, but also in the panels adjacent to the expansion joints, as this increases the longitudinal rigidity of the upper part of the frame; In addition, during the construction of a workshop, each temperature block can for some time constitute an independent structural complex.
Vertical_connections_between_columns are installed along all rows of columns of the building; their location should be between~ the same axes.
52. Connections along the tent of a one-story industrial building. Installation diagrams. Structural forms
. Elements of tent connections are calculated, as a rule, based on flexibility. The maximum flexibility for compressed elements of these connections is 200, for stretched ones - 400 (for cranes with a number of cycles of 2X10 6 or more - 300). You can determine whether a link element is stretched or compressed by taking into account What connections perceive conditional transverse forces Q yca (both during operation and during installation), wind influences on the end of the building F BT ,
longitudinal and transverse forces of overhead cranes and that all these forces can be directed in one direction or the other (see Fig. 11.12). 
53.54. Covering structures. Coverings by purlins. Sections of continuous purlins. Design and calculation
. The covering of an industrial building can be done with or without purlins. In the first case, between the trusses, purlins are installed every 1.5-3 m, on which small-sized roofing slabs, sheets, and decking are laid. In the second case, large slabs or panels 1.5-3 m wide and 6 or 12 m long are laid directly on the trusses, combining the functions of load-bearing and enclosing structures | Roofing along purlins is lighter due to the short span of enclosing elements, but requires greater metal consumption (for purlins) and is more labor-intensive to install. The purlins are installed on the upper chord of the trusses at their nodes. Rolled beams, bent sections or light through structures (with truss spacing greater than 6 m) are used as purlins. Roof coverings can be warm (with insulation) in heated industrial buildings and cold without insulation (for unheated buildings) 
55. Crane structures. Compound. Basic structural forms
. Crane structures perceive impacts from various lifting and transport equipment. The main type of such equipment is overhead support and overhead cranes. Crane structures for overhead supporting cranes (Fig. 15.1) consist of crane beams or trusses 1,
absorbing vertical loads from cranes; brake beams (trusses) 2,
perceiving transverse horizontal impacts; connections 3,
ensuring rigidity and immutability of crane structures; attachment points for crane structures that transmit crane impacts to columns; crane rails 4
with elements of their fastening and stops. The main load-bearing elements of crane structures, crane beams, can have different structural shapes. Most often, solid crane beams are used as split beams (Fig. 15.2, A), and continuous (Fig. 15.2, b)..
56.Load collection, determination of forces in a continuous crane beam . Loads from the crane are transferred to the crane structure through the wheels (rollers) of the crane located on the end beam of the crane bridge. Depending on the lifting capacity of the crane, there may be two, four or more rollers on each side of the bridge (Fig. 15.6, a, b).
Crane structures are designed, as a rule, for loads from two closely spaced cranes of the highest lifting capacity (Fig. 15.6, e) with trolleys close to one of the rows of columns, i.e. in a position in which the greatest vertical forces act on the crane structures. At the same time, maximum transverse horizontal forces are applied to the beam. 
The calculated values of vertical and horizontal forces are determined by the formulas: 
When calculating crane structures for cranes of heavy and very heavy operating modes, the horizontal load caused by crane misalignment is taken into account, therefore the force Г" is determined by the formula 
57. System for checking a continuous crane beam
.
Checking the strength of crane beams. Under under the action of vertical and horizontal crane loads, the crane beam and the brake structure work as a single thin-walled rod for oblique bending with torsion (Fig. 1.5.11, A), 
the upper chord of the beam is subject to both vertical and horizontal loads, and the maximum stresses at the point A(Fig. 15.11.6) can be determined by the formula 
Deflection check crane beams are made according to the rules of structural mechanics or an approximate method. With sufficient accuracy, the deflection of split crane beams can be defined by the formula where M- bending moment in the beam from the load of one crane with u=1.0; in continuous beams where M l , Mer, M P r - respectively, the moments on the left support, in the middle of the span and on the right support. Local resistance crane beam elements are checked in the same way as conventional beams.
58. Columns industrial buildings. Columns of constant cross-section. Design and calculation. In columns of constant height section (Fig. 14.1, A) the load from the overhead cranes is transferred to the column core through the consoles on which the crane beams rest. The column core can be of solid or through section. The great advantage of columns of constant cross-section (especially solid ones) is their structural simplicity, which ensures low manufacturing complexity. These columns are used when the cranes have a relatively small lifting capacity (Q up to 15-20 tons) and a small workshop height (H up to 8-10 m).
N, M X M at ) and shear force Q x
59Stepped columns. Calculation and design .
For large-capacity cranes, it is more profitable to switch to stepped columns (Fig. 14.1, b, c, d), which are the main type of columns for one-story industrial buildings. The crane beam in this case rests on the ledge of the lower section of the column and is located along the axis of the crane branch. In buildings with cranes located in two tiers, the columns can have three sections with different sections in height (two-stage columns), additional consoles, etc.
Columns industrial buildings work on eccentric compression. Design force values: longitudinal force N, bending moment in the plane of the frame M X (in some cases, the bending moment acting in another plane is M at ) and shear force Q x determined based on the results of static calculations of the frame (see Chapter 12). When calculating a column, it is necessary to check its strength, general and local stability of the elements. To ensure normal operating conditions, columns must also have the necessary rigidity.
60. Columns of separate type. Calculation and design. In separate columns (Fig. 14.2), the crane pillar and the tent branch are connected by horizontal strips that are flexible in the vertical plane. Thanks to this, the crane rack absorbs only the vertical force from the cranes, while the tent rack works in the transverse frame system and absorbs all other loads, including the horizontal lateral force from the cranes.
Separate-type columns are rational for low locations of heavy-duty cranes and for reconstruction of workshops (for example, during expansion). 
1. Beam structures. Beam classification .
Beams are the basic and simplest structural element, working on bending. 
The wide distribution of beams is determined by the simplicity of the design of manufacture and reliability in operation. In the structures of small spans up to 15-20 m long, it is most rational to use solid beams. As the load increases, the length of the spans increases; there are known examples of the use of continuous spans that are smaller than average to maintain a constant cross-section, then their structures are non-mass (individual), and their use is relatively rare.
2. Types of beam cells. Layout of beam structures
. Beam cells are divided into three main types: simplified, normal and complicated (Fig. 7.3). 
In a simplified beam cage (see Fig. 7.3, A) the load on the floor is transferred through the flooring to the floor beams, which are usually located parallel to the smaller side of the floor at distances A(beam pitch) and through them onto walls or other bearing structures, limiting the site. Due to the small load-bearing capacity of the deck, the beams supporting it have to be installed frequently, which is rational only for small spans. in a normal type of beam cage (see Fig. 7.3.6), the load from the flooring is transferred to the flooring beams, which in turn transfer it to the main beams resting on columns, walls or other load-bearing structures that limit the site. Flooring beams are usually accepted as rolled ones. In a complicated beam cage (see Fig. 7.3, e), additional, auxiliary beams are introduced, located between the floor beams and the main beams that transfer the load to the columns. In this type of beam cage, the load is transmitted to the supports for the longest time. To reduce the labor intensity of flooring, deck beams and auxiliary beams are usually adopted as rolled steel.
3. Calculation and design of beam joints (floor-by-floor on one level) . The pairing of beams can be storey, at the same level, or lower.
When connecting floors (Fig. 7.4, A) beams directly supporting the flooring are laid on the main or auxiliary ones. This is the simplest and most convenient installation method for connecting beams, but it requires the greatest building height. When paired at the same level (see Fig. 7.4,6), the upper flanges of the flooring beams and the main beams are located at the same level, and the flooring rests on them. This method allows you to increase the height of the main beam at a given construction height of the floor, but significantly complicates the design of supporting the beams.
Reduced coupling (see Fig. 7.4, c) is used in beam cages of a complicated type. In it, auxiliary beams are adjacent to the main one below the level of the upper chord of the main one, and beams with flooring are laid on them floor by floor, which are located above the main beam. This type of coupling, as well as coupling at one level, allows you to have the greatest height of the main beam for a given construction height of the floor.
4. Flooring of beam cages. Calculation and design . The flooring of beam cages can be very diverse depending on the purpose and design of the floor. Very often, a protective deck is installed on top of the load-bearing deck, which can be made of wood, asphalt, brick and other materials.
Flat steel sheets or precast concrete slabs are most often used as load-bearing decking. 
from the condition of a given maximum deflection 
Strength N, the effect of which it is necessary to check the welds attaching the decking and its supporting structure can be determined by the approximate formula 
5. Selection of cross-section for elastic and elastoplastic operation of rolled beams .
Calculation of the strength of rolled beams bent in one of the main planes is carried out using the bending moment according to the formula. Therefore, the required moment of resistance of the “net” beam can be determined by the formula. Having selected the type of beam profile according to the required moment of resistance, the nearest larger number of the beam is selected according to the assortment. For split beams of continuous section made of steel with a yield strength of up to 580 MPa, under the influence of static load, ensured against loss of overall stability and a limited amount of tangential stresses in one section with the most unfavorable combination M and Q, you should use the elastoplastic work of the material and check their strength using the formulas: For the case of taking into account the elastoplastic work when bending a beam in one of the main planes, the selection of sections can be made according to the required net moment of resistance using the formula 
6. Verification of rolled beams for the first and second groups of limit states .
first group- loss of load-bearing capacity and (or) complete unsuitability for use of structures; second group- due to difficulties in the normal operation of structures. The selected section is checked for strength under the action of tangential stresses using the formula. The second limit state (providing conditions for normal operation of the structure) is checked by determining the deflection of the beam under the action of standard loads, assuming elastic operation of the material. The resulting relative deflection is a measure of the beam’s rigidity and should not exceed the standard value, depending on the purpose of the beam. For a single-span beam loaded with a uniformly distributed load, the deformability check is carried out according to the formula
In trusses with rods made of two angles formed by a brand, the nodes are designed on gussets that are inserted between the angles. The lattice rods are attached to the gusset by welding the corners along the contour or using continuous flank seams. In the latter case, the ends of the flank seams are brought out to the ends of the element to a length of 20 mm (Fig. 27).
If possible, the gussets extend beyond the edges of the waist corners by 10...15 mm and are attached to them with continuous seams. In the place of support of the rolling purlins (with a truss pitch of 6 m), the gussets are not brought to the butts by 10...15 mm and this place is not welded. To attach the purlins to the upper chord of the truss, a corner with holes is welded at the nodes (see Fig. 27).
If possible, the gussets of the units should be given a rectangular or trapezoidal shape.
When the belt is continuous in the node, calculations are usually made for attaching the lattice rods to the gusset of the node. In the case of using the same grade of steel for all rods, the required length of the weld is determined by its strength according to the formula: 
,
where N is the design force in the rod; – coefficient of penetration of the root of a fillet weld (for manual welding it is equal to 0.7); k f – leg of the weld, usually taken to be equal to the thickness of the corner flange (and the same for the feather and butt); – coefficient of operating conditions of the structure (for roof trusses it can be taken equal to 0.95); - weld operating condition coefficient equal to 0.85, during construction in I 1, I 2, II 2 and II 3 climatic regions and the use of E42 type electrodes and - in other cases; - design resistance of fillet weld metal.
The length of the seam along the hem and feather of one corner is determined accordingly by the formulas: and . The length of the flank seam must be at least 40 mm and not less. In the case of designating a seam leg along the butt that is larger than along the feather, the length of the seam along the butt and feather of one corner will be determined accordingly according to the formulas: 
And 
.
Trusses with a span of more than 18 m are manufactured in factories in sending parts (two or more). A variant of the enlarged joint of semi-trusses is shown in Fig. 28. At the joint, the total cross-sectional area of the linings is taken to be no less than the cross-sectional area of the two waist (joined) corners. The length of the weld seams for attaching each pad (on one side of the joint) is determined by a force equal to its load-bearing capacity. A detailed calculation of the butt joints of the semi-trusses is given in.
The design of the corner truss support units is shown in Fig. 29. The calculation and design of these units is given in.
Literature
1. Metal constructions. Volume 1. Structural elements. Ed. prof. V.V. Goreva. M.: Higher school. 2001, 1997. –528 p.
2. SNIP P-23.81*. Steel structures. M.: CITP. 2001. -96 p.
3. GOST 21.501-93. Rules for the execution of architectural and construction drawings. M.: State Unitary Enterprise TsPP. 1998. -58 p.
4. Metal structures. Volume 2. Building structures. Ed. prof. V.V. Goreva. M.: Higher school. 2001, 1999. –528 p.
5. Section “Metal structures” in the folder “Student – PGS” of the “Z” drive on the computer server of the department “Building structures”.
6. Likhtarnikov Ya.M. Variant design and optimization of steel structures. M.: Stroyizdat. 1979. -319 p.
7. Mandrikov A.P. Examples of calculations of metal structures. M.: Stroyizdat. 1991. -431 p.
8. Vasilchenko V.T. and others. Handbook of steel structures designer. Kyiv. Budivelnik. 1990. –312 p.
9. SNIP 2.01.07-85*. Loads and impacts. M.: State Unitary Enterprise TsPP. 2001. -43 p.
10. Metal structures. Ed. prof. E.I. Belenya. M.: Stroyizdat. 1986. –560 p.
11. Likhtarnikov Ya. M. et al. Calculation of steel structures: Reference manual. -Kiev: Budivelnik, 1984. -366 p.
12. Biryulev V. V. et al. Design of metal structures. Special course. -L.: Stroyizdat, 1990. –432 p.
13. Designer's Handbook. Metal structures: In 3 t / Ed. prof. V. V. Kuznetsova. Place publishing house ASV, 1998. T. 2. –504 p.
14. Nilov A. A. et al. Steel structures of industrial buildings: Handbook. –Kiev: Budivelnik, 1986. –272 p.
15. GOST 16350-80. Climate of the USSR. Zoning and statistical parameters of climatic factors for technical products. -M.: USSR State Committee for Standards, 1981. -140 p.
16. Endzhievsky L.V. et al. Building frames made of light metal structures and their elements. -M.: Publishing House ASV, 1998. -246 p.
17. Designer's Handbook. Metal structures: In 3 t / Ed. prof. V. V. Kuznetsova. -M.: Publishing house ASV, 1998. T. 1. –575 p.
18. Metal structures / Ed. Yu.I.Kudishina. M:, ACADEMA. 2006- -681 p.
APPLICATIONS
Annex 1
lifting capacity from 12.5 to 50/12.5 t normal type
regime group 5K (extract from GOST 25711-83)
Table 1.1
| , T | , m | , kN | , T | , T | , m | ,m |
| 12,5 | 16,5 | 3,0 | 16,0 | 1,9 | 5,5/4,4 | |
| 22,5 | 20,5 | |||||
| 28,5 | 26,0 | 6,1/5,0 | ||||
| 34,5 | 32,0 | 6,7/5,6 | ||||
| 16,5 | 3,7 | 18,7 | 2,2 | 5,6/4,4 | ||
| 22,5 | 21,7 | |||||
| 28,5 | 28,5 | 6,2/5,0 | ||||
| 34,5 | 39,0 | 6,8/5,6 | ||||
| 16/3,2 | 16,5 | 4,7 | 20,0 | 5,6/4,4 | ||
| 22,5 | 23,0 | |||||
| 28,5 | 29,0 | 6,2/5,0 | ||||
| 34,5 | 40,3 | 6,8/5,6 | ||||
| 20/5 | 16,5 | 6,3 | 22,0 | 2,4 | 5,6/4,4 | |
| 22,5 | 25,5 | |||||
| 28,5 | 33,2 | 6,2/5,0 | ||||
| 34,5 | 46,5 | 6,8/5,6 | ||||
| 32/5 | 16,5 | 8,7 | 28,0 | 2,75 | 6,3/5,1 | |
| 22,5 | 35,0 | |||||
| 28,5 | 41,0 | |||||
| 34,5 | 56,5 | 6,8/5,6 | ||||
| 50/12,5 | 16,5 | 13,5 | 41,5 | 3,15 | 6,86/5,6 | |
| 22,5 | 48,5 | |||||
| 28,5 | 59,5 | |||||
| 34,5 | 73,1 |
Required parameters and dimensions of electric bridge cranes
with a lifting capacity from 12.5 to 50 tons of lightweight type
regime group 3K (extract from GOST 25711-83)
Table 1.2
| , T | , m | , kN | , T | , T | , m | ,m |
| 12,5 | 16,5 | 3,0 | 10,3 | 1,9 | 5,5/4,4 | |
| 22,5 | 14,1 | |||||
| 28,5 | 17,8 | 6,1/5,0 | ||||
| 34,5 | 21,6 | 6,7/5,6 | ||||
| 16,5 | 6,3 | 14,9 | 2,4 | 5,6/4,4 | ||
| 22,5 | 20,3 | |||||
| 28,5 | 25,7 | 6,2/5,0 | ||||
| 34,5 | 31,1 | 6,8/5,6 | ||||
| 16,5 | 8,7 | 21,1 | 2,75 | 6,3/5,1 | ||
| 22,5 | 28,8 | |||||
| 28,5 | 36,5 | |||||
| 34,5 | 44,2 | 6,8/5,6 | ||||
| 16,5 | 13,5 | 28,9 | 3,15 | 6,86/5,6 | ||
| 22,5 | 39,4 | |||||
| 28,5 | 49,9 | |||||
| 34,5 | 60,4 |
Required parameters and dimensions of electric bridge cranes
with a lifting capacity from 12.5 to 50 tons heavy type
regime group 7K (extract from GOST 25711-83)
Table 1.3
| , T | , M | , kN | , T | , T | , m | ,m |
| 12,5 | 16,5 | 3,0 | 23,0 | 1,9 | 5,5/4,4 | |
| 22,5 | 29,5 | |||||
| 28,5 | 38,0 | 6,1/5,0 | ||||
| 34,5 | 48,0 | 6,7/5,6 | ||||
| 16,5 | 6,3 | 28,5 | 2,4 | 5,6/4,4 | ||
| 22,5 | 36,0 | |||||
| 28,5 | 46,5 | 6,2/5,0 | ||||
| 34,5 | 57,5 | 6,8/5,6 | ||||
| 16,5 | 8,7 | 42,5 | 2,75 | 6,3/5,1 | ||
| 22,5 | 52,0 | |||||
| 28,5 | 62,0 | |||||
| 34,5 | 73,0 | 6,8/5,6 | ||||
| 16,5 | 13,5 | 58,0 | 3,15 | 6,86/5,6 | ||
| 22,5 | 69,0 | |||||
| 28,5 | 79,0 | |||||
| 34,5 | 86,0 |
Appendix 2
Snow, wind and climatic regions of some cities
Far East
| City (Construction area) | Districts (by and | ||
| Snow | Wind | Climatic | |
| 1. Anadyr | V | VII | II 4 |
| 2. Alexandrovsk-Sakhalin. | V1 | V | II 4 |
| 3. Birobidzhan | II | III | II 4 |
| 4. Blagoveshchensk | I | III | II 4 |
| 5. Vladivostok | II | IV | II 6 |
| 6. Komsomolsk-on-Amur | IV | III | II 4 |
| 7. Magadan | V | V | II 4 |
| 8. Nikolaevsk-on-Amur | V | IV | II 4 |
| 9. Petropavlovsk-Kamchat. | VI1 | VII | II 6 |
| 10. Pevek | IV | IV | II 2 |
| 11. Khabarovsk | II | III | II 4 |
| 12. Yuzhno-Sakhalinsk | VI | VI | II 4 |
Appendix 3
The sum of the ordinates of the line of influence of the support reaction of a split crane beam during joint operation of two overhead cranes
| Crane characteristics | at column spacing | |||
| , T | Work mode | , m | 6 m | 12 m |
| 12,5 | 3K, 5K, 7K | 16,5; 22,5 28,5 34,5 | 2,167 1,983 1,883 | 3,083 2,983 2,883 |
| 16; 16/3,2 | 5K | 16,5; 22,5 28,5 34,5 | 2,133 1,967 1,867 | 3,067 2,967 2,867 |
| 3K, 7K | 16,5; 22,5 28,5 34,5 | 2,133 1,967 1,867 | 3,067 2,967 2,867 | |
| 20/5 | 5K | 16,5; 22,5 28,5 34,5 | 2,133 1,967 1,867 | 3,067 2,967 2,867 |
| 3K, 7K | 16,5…28,5 34,5 | 1,950 1,867 | 2,950 2,867 | |
| 32/5 | 5K | 16,5…28,5 34,5 | 1,950 1,867 | 2,950 2,867 |
| 3K, 7K | 16,5…34,5 | 1,857 | 2,857 | |
| 50/12,5 | 5K | 16,5…34,5 | 1,857 | 2,857 |
Introduction……………………………………………………………………3
1. Composition of the course work……………………………………...........…4
1.2.1. Sheet1 (KM)…………………………….…..…............................ .. ......5
1.2.2. Sheet 2 (KMD)…………………………………………...........................5
1.2.3. Sheet 3 KM)………………………………………………………………5
2. Instructions for performing calculations…………………...................... ...........6
2.1. Calculation of the flooring and rolled beams of the beam cage……………..…..6
2.1.1. Calculation of steel flooring………………………………………………………...........6
2.1.2. Calculation of flooring beams………………………………………….……..7
2.1.3. Calculation of the auxiliary beam………………………………………………………9
2.2. Calculation of the welded main beam…………………………………...……..10
2.2.1. Calculation scheme. Loads. Efforts…………………………..............11
2.2.2. Selection of section……………………………………………………......12
3.2.3. Changing the section………………………………………………………......15
2.2.4. Supporting part……………………………………………………………………...16
2.2.5. Structural support for wall stability………………17
2.2.6. Checking the strength, stiffness and stability of the beam
and its elements…….................................................. ........................... .......….118
2.3. Calculation of a solid section column……………………………………22
2.3.1. Calculation scheme. Efforts……………………………………………………………22
2.3.2. Selection of the section of the column rod……………… ...........................23
2.3.3. Checking rigidity, general and local strength
stability of the column and its elements…………………................................25
2.3.4. Design and calculation of the head………………...…...... ...…...26
2.3.5. Design and calculation of the base…………………........................... .........27
2.4. Design and calculation of element interface nodes
beam cage……………................................................... ............... ..… 29
2.4.1. Calculation of flooring attachment……………....……............................29
2.4.2. Calculation of the floor support unit for the flooring beam on
auxiliary beam…………................................................... ........... .... .. thirty
2.4.3. Calculation and design of a unit for reduced support of beams....31
2.4.4. Design of equal-strength mounting (enlargement)
main beam assembly…………………............................................ ...... .. ..... 32
3. Frame layout……………………………………………..33
3.1. Column grid…………………………………………………………….. 33
3.2. Cross frame layout …………………………………………34
3.2.1. Determination of vertical dimensions……………………………..34
3.2.2. Determination of horizontal dimensions ………………………….35
3.3. Crossbar layout……………………………………………..……….36
3.4. Layout of connections between columns ………………………………….36
3.5. Layout of connections on the coating…………………………………….37
3.6. Layout of the end half-timbering ………………………………………38
4. Determination of design forces in the frame strut……………………….39
4.1. Calculation scheme……………………………………………………….39
4.2. Loads on cross frame ………………………………………..39
4.2.1. Constant loads………………………………………………………40
4.2.3. Crane loads……………………………………………………………42
4.2.4. Wind loads…………………………………………….43
4.3. Static calculation of the frame………………………………………………………..44
5. Calculation of the roof truss………………………………………………………46
5.1. Determination of the design load of forces in the truss rods……..46
5.2. Selection of rod sections ………………………………………………………47
5.3. Calculation and design of truss nodes from paired angles…….49
Literature……………………………………………………51
Appendix 1. Parameters of overhead cranes ………………… .....52
Appendix 2. Zoning of cities of the Far East ... 54
Appendix 3. Sum of ordinates of the influence line of the reference
reactions of a split crane beam……………………… … 54
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