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Why is steel construction the preferred choice for large-span spatial structures?

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When gazing upon grand stadiums , airport terminals, or exhibition centers, we are often awestruck by their vast spaces. Behind such large-span structures lies a nearly universal choice—steel construction. This is no coincidence, but stems from steel's unparalleled engineering advantages. stadium High Strength, Lightweight: Pushing Boundaries Beyond Limits The core advantage of steel lies in its perfect blend of exceptional strength and lightweight properties. Compared to concrete, steel boasts an outstanding strength-to-weight ratio. This means that for buildings requiring vast column-free spaces, steel structures can achieve greater spans with smaller member cross-sections, significantly reducing the building's self-weight. Consequently, foundation requirements are lowered, enabling the ultimate liberation of space in a cost-effective manner. Exceptional Performance, Conquering Complex Challenges Steel's outstanding toughness and ductility enable it to better withstand dy...
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Disadvantages of prestressed concrete structures

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Concrete Steel Structure
Concrete Steel Structure

1. The process is more complex, high quality requirements, thus requiring a more skilled professional team, and there are problems of interspersed types of work.

2. Sub-stress. Secondary stresses due to prestressing, creep and shrinkage effects, temperature variations, and bearing subsidence can be severe in continuous structures unless these are controlled or accounted for in the design. In prestressed continuous structures, it is interesting to note that these secondary stresses can often be exploited advantageously, and thus the secondary stresses will increase the economy of the structure.

3. Friction losses in continuous force bars. Friction losses can be significant if there are many reverse curves, if the curves have large deflection angles, or if the force bars are too long. In beams with corrugations or added axils, friction losses can be minimised by using straighter cables. The usual methods of over-tensioning and tensioning from both ends can also be used to minimise friction losses.

4. Certain specialised equipment is required, such as tensioning rigs and grouting equipment. Pre-tensioning method requires a tensioning pedestal; post-tensioning method also consumes a larger number of reliable quality of anchorage, etc.. However, now the more widely used slow bond prestressing is a great improvement on this basis.

5. The start-up cost of prestressed concrete structure is larger, and the cost is higher for projects with a small number of members.

6. Prestressed reverse arch is not easy to control. It increases with the increase of concrete creep, causing the structure to finish unevenly. Especially the pre-stressed prefabricated members are more significant, the anti-arch is not coordinated, and the cracking problem of the members brings more difficulties to the site.

7. Under high temperature conditions, the strength of reinforced concrete after applying prestressing will be significantly reduced, leading to a decrease in its fire resistance limit, so there are safety hazards in building fire protection.

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What is a coal bunker?

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Coal bunker , is a structure used for storing coal. Coal bunkers play an important role in thermal power plants, coal mines and coal marshalling stations. Depending on the specific application scenario and design, there are various types of coal bunkers, such as circular coal bunkers, square coal bunkers and open coal yards. Safety Management of coal bunkers Preventing spontaneous combustion of coal: Since coal itself contains certain moisture and volatile substances, long-term exposure to the air may lead to spontaneous combustion, so the safe management of coal bunkers is of great significance in preventing spontaneous combustion of coal. Ensure the quality of coal: coal in the coal bunker usually needs to be stored for a long time, if not managed properly, it may lead to the decline in the quality of coal, such as sulphurisation, weathering and other phenomena, so it is necessary to ensure the quality of coal by strengthening the safety management of the coal bunker. Improve the eco...
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What is the difference between a single-layer reticulated shell and a double-layerreticulated shell?

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  The differences between single-layer reticulated shells and double-layer reticulated shells are as follows: Structural Configuration   Single-layer reticulated shell: Composed of a single layer of members, with the members directly connected to form a grid structure . The node configuration is relatively simple, typically employing rigid connections that allow the members to bear not only axial forces but also bending moments and shear forces.   Double-layer reticulated shell: Consists of upper and lower parallel layers of members connected by web members, forming a truss-like structural system. The nodes are generally hinged, and the members primarily bear axial forces. Its configuration is relatively complex, requiring more members and nodes to ensure structural stability and load-bearing capacity. Structure Single-layer mesh shell: composed of one layer of rods, the rods are directly connected to form a mesh structure, the node structure is relatively simple, usually...
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Suspension structures

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 A suspension structure is a structural form that carries roof loads through a series of high-strength steel cables. Its main load-bearing member is the cables, which are usually steel cables made of high-strength steel wires. The roof of the suspension structure is generally light and thin, and its shape can be very flexible, able to realize the large span across. For example, in the roofs of some large conference centers or exhibition halls, the suspension structure can create unique shapes such as double-curved paraboloid or single-curved paraboloid, which make the building have a strong artistic influence. Suspension structures require a stable support structure to anchor the steel cables, usually using reinforced concrete columns or steel columns as support. And in order to ensure the stability of the structure, it is also necessary to set a certain amount of prestressing, so that the steel cables are in a tensioned state before they are subjected to loads. Scope of applicatio...
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