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Color steel plate storage

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  Color steel plate Color steel plate , despite the double protection of galvanized layer and organic coating on the surface of the steel plate, if it is in a humid state for a long time, the water accumulated on the surface (including water produced by condensation in the air) will gradually infiltrate through the organic coating, thus causing corrosion of the zinc layer under the film of the organic coating, so attention must be paid to it when it is stored: (1) Not to be wet by water, stored indoors, avoiding open stacking. (2) The room should be dry and ventilated, without corrosive gases, and must avoid being placed in a place that is prone to condensation as well as the big temperature difference between cold and warm. Forced to temporarily store outdoors, underneath must have a square sleeper for cushion wood, and pay attention to good ventilation, choose flat ground, cushion wood above should also be horizontal, to make the steel plate stacked at the same height, to prevent the
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What is the difference between a girder, rafter, and purlin in steel structures?

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  In steel structures , girders, rafters, and purlins are all structural components that play different roles in supporting the building's load and providing stability. Here's a breakdown of each: 1. Girder:     - A girder is a large horizontal beam that supports other beams or loads across an open space, such as a roof or floor.     - Girders are typically placed perpendicular to the beams they support and are designed to carry heavy loads over long spans.     - In steel construction, girders are often used in building frames and bridges to distribute loads from the beams to the columns or supports. 2. Rafter:     - A rafter is a sloped structural member that supports the roof covering and transfers its load to the walls or other supporting elements.     - Rafters are commonly used in roof framing to provide structural support and to create the pitched shape of the roof.     - In steel construction, rafters are often made from steel beams or trusses and are spaced at regular i
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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 280g/m2
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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 ground.
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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 tends to
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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
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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 cone network frame, p
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