博文

目前显示的是 五月, 2024的博文

Design of steel structures against corrosion (II)

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  Steel Structure Surface Related Design Anti-corrosion Coating 1. The adhesion between the anti-corrosion coating and steel base should not be lower than 5MPa. 2. For newly designed steel structures , it is not suitable to use rust coating for descaling and painting, and when rust coating is required for repairing the steel structures of existing buildings, it should be used after the demonstration. 3. The fireproof coating on the surface of the steel structure generally does not have an anticorrosive effect, so the fireproof coating should not be used as an anticorrosive coating. The surface of the steel structure should be coated with antirust primer, corrosion-resistant intermediate coating, fireproof coating, and then anticorrosive surface coating according to the structure of protection treatment. 4. Galvanized steel plating amount of micro-corrosive, weak corrosion or corrosive environment in the double-sided galvanized amount should not be less than 180g/m2, 250g/m2, or 280...

Design of steel structures against corrosion (I)

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  Design related to different structural elements Anti-corrosion Coating 1. The friction surface of high-strength bolt connection should be processed strictly according to the design requirements, and ensure that the anti-slip coefficient meets the requirements of the bearing capacity, without special requirements, its rust removal level should be the same as the rust removal level of the main material. 2. When the connection is in the open air or in a moderately corrosive environment, the friction surface after descaling should be coated with inorganic zinc-rich primer or zinc plus primer coating level structure, and the thickness of the coating should not be less than 70μ. 3. Common bolts in moderately corrosive environments shall be galvanized bolts. 4. The buried part of the steel column foot should be wrapped with dense concrete of strength class not less than C20 (the thickness of the protective layer should not be less than 50mm), and not less than 50mm above the indoor grou...

What is a fish-belly steel joist?

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  The structure of this fish-belly steel joist is composed of the upper chord, a web, and a folded lower chord, the ends of the folded lower chord are connected with the ends of the upper chord, and the upper and lower ends of the web are welded between upper chord and folded lower chord in the form of bending moment graphic arrangement, which is like the belly of a fish, and there are also end plates connected with the ends of upper chord. Compared with the existing technology, the fish-belly steel joist has the features of reasonable design, simple structure, easy processing, easy to use, labor-saving and time-saving, and large bearing capacity, and therefore, it has a good value of popularization and use.  fish-belly steel joist One of the characteristics of a fish-belly steel joist is that it is surrounded by a top chord and a folded bottom chord to form an approximate simple bending moment diagram, which is shaped like the belly of a fish. The axial force between chords ...

Design Principle of Fish Belly Beam

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  Fish Belly Beam The design principle of the fish-belly beam is mainly based on its unique structural form, which has a beam with a large middle part of the cross-section and then gradually decreases towards the ends, similar to the shape of a fish's belly. The main purpose of this design is to increase the bending strength of the beam while saving material. Specific applications of fish-belly girders include structures consisting of steel strands and steel trusses with spans that can reach over 60m. By applying prestressing force to the steel strands, a large reaction force can be generated to the supporting bars of the fish-belly girders, which significantly reduces the bending moment acting on the purlins of the fish-belly girders and improves the bending stiffness of the girders. In addition, the prestressed fish-belly girders can be connected together with angle braces or buttress girders through specialized nodes to form a support system for deep foundation pits. Explore the...

Selection of space frame structure (II)

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 Factors affecting the selection of space frames  mainly include space frame  production, installation methods, steel indicators, span size, stiffness requirements, plane shape, support conditions, and so on. space frame 5, the stiffness of the space frame   is much better than the plane roof frame, but between the various kinds of space frame , whether it is the horizontal stiffness or vertical stiffness, the difference is not small. A diagonally placed quadrangular cone space frame , is geometrically variable in itself, in the addition of edge members or a strong ring beam to ensure its geometric invariance. Generally speaking, the number of nodes and the number of rods is larger network frame, such as triangular cone network frame, hexagonal cone network frame, three-way network frame, and positive release quadrangular cone network frame, its stiffness is larger, on the contrary, such as diagonal release quadrangular cone network frame, tessellated quadrangular co...

Selection of space frame structure (I)

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  Factors affecting the selection of space frames  mainly include space frame   production , installation methods, steel indicators, span size, stiffness requirements, plane shape, support conditions, and so on. space frame 1 、 If the nodes are welded, the space frame   composed of a plane truss system is more convenient to make than the space frame   composed of the quadrangular cone; the two-way orthogonal space frame   is more convenient than the two-way diagonal space frame,   and three-way space frame ; the quadrangular cone space frame   is more convenient than the triangular cone space frame . 2, when the installation method of the space frame   is not used as a whole lift or hoisting, but the use of strip or block installation, or the use of high-altitude skidding method, the choice of the two-way orthogonal orthogonal space frame , orthogonal orthogonal cone space frame , orthogonal orthogonal four-cone space frame , four-cone space ...

What type of steel connection is the articulated connection suitable for?

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  articulated connection The articulated connection is mainly used for the connection of beams and columns in steel structures , especially where it is necessary to allow the two structural members to rotate relative to each other within a certain range. This type of connection is usually used for flexible connections, in contrast to rigid and semi-rigid connections. In an articulated connection, the connecting nodes are not subjected to significant deformation of the connection angle, thus maintaining the overall stability and resistance of the structure. Articulated structures usually use double angles, end plates, single shear plates and double shear plates as connectors. In steel structures, it is usually used as a connection structure connecting primary and secondary beams, and can also be applied in the structural splicing of inclined beams. For example, double angles can be welded on both sides of the web of the secondary beam, and at the same time connected with the main be...