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How to Fix and Prevent Roof Leakage in Light Steel Structures

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Roof leakage is one of the most common problems in light steel workshops and warehouses. It not only affects daily use but also causes internal corrosion, shortens the building’s service life, and leads to higher maintenance costs. Most leakage happens at panel joints, screw holes, flashing areas, or around openings. The main reasons are poor waterproof treatment, aging sealant, loose screws, or improper installation. To fix existing leaks, first clean the surface and locate the leakage points. Replace damaged or aging sealing strips. Re-tighten loose screws or replace them with waterproof self-drilling screws. Apply professional waterproof sealant at joints and openings. For serious cases, add a layer of waterproof coating to improve protection. To prevent future leakage, use high-quality roof panels and waterproof materials from the beginning. Ensure professional installation with standard flashing and sealing design. Conduct regular inspections, especially before rainy seasons, and ...
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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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Structural Steel Bolting Balls: Connecting the Future, Securing the Cornerstone

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