Featured Articles

Under the Dome, Defining New Landmarks in East Africa: Empowering Public Spaces with Our Bespoke Design

-
图片
  On the skylines of Nairobi, Addis Ababa, and Dar es Salaam, modern municipal buildings are rising. With East Africa’s economic growth and the preparation for major international events and cultural festivals, stadiums, museums, and convention centers are no longer just functional structures – they have become the “calling cards” that showcase a city’s ambition and vitality.   However, when developing such large-scale public buildings, owners and government bodies often face a key challenge: how to achieve unobstructed, large-span spaces while balancing aesthetics and safety? Traditional concrete structures struggle to meet the open-view requirements of stadiums or the artistic fluidity of museums. That is exactly where our expertise comes in. As a team specialized in steel structure design with multiple successfully delivered municipal projects in East Africa, we deeply understand the social significance of these buildings. We provide not just steel structures, but fully tai...
发表评论

Disadvantages of prestressed concrete structures

-

 

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.

评论

发表评论

此博客中的热门博文

What is a coal bunker?

-
图片
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...
阅读全文

What is the difference between a single-layer reticulated shell and a double-layerreticulated shell?

-
图片
  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...
阅读全文

What are the differences between bolted ball grids and welded ball grids?

-
图片
 There are a number of differences between bolted ball grids and welded ball grids in terms of fabrication, construction and design. The following are specific comparisons: 1. Manufacturing process: The manufacturing of bolted ball net frame is mainly carried out in the factory, using mechanical shot blasting to remove rust, and then spraying paint, plastic spraying or zinc spraying treatment to enhance corrosion resistance.  The steel pipe and welded seam of welded ball mesh frame can only be descaled manually on site, and then paint or fireproof coating is brushed. For the welded part, it needs to be descaled and brushed at a stage to maintain, which increases the cost of later use and affects the safety of the structure. 2. Construction process: 70% of the workload of bolted ball grid frame is prefabricated in the factory, 30% of the workload is installed at the site, only a wrench is needed to tighten the bolts at the site, which is easy and fast, and can be constructed ...
阅读全文