Heshan Prefabricated Houses

Currently, no direct and comprehensive information about 'Heshan Prefabricated Houses' has been found, but relevant popular science can be conducted by combining the current situation of some prefabricated panel structure residences in Heshan.

Current Situation of Some Prefabricated Panel Structure Residences in Heshan

Among the brick-concrete structure buildings built before 1990 in Heshan City, some prefabricated panel structure residences have shown signs of steel bar corrosion and concrete carbonation. Prefabricated panel structure residences were a common form of architecture in the early days. The prefabricated panels are floor components pre-made in factories and then transported to construction sites for installation and assembly. This construction method had the advantages of fast construction speed and high efficiency at that time, meeting the needs of rapid construction.

Impacts of Steel Bar Corrosion and Concrete Carbonation

• Steel Bar Corrosion: Steel bars are key components that bear tensile forces in prefabricated panel structures. When steel bars corrode, their effective cross-sectional area gradually decreases, leading to a decline in their mechanical properties and load-bearing capacity. At the same time, the volume expansion of the rust produced by steel bar corrosion exerts pressure on the surrounding concrete, causing cracks in the concrete. This further accelerates the corrosion process of steel bars, forming a vicious cycle and seriously affecting the safety and durability of prefabricated panel structures.
• Concrete Carbonation: Concrete carbonation refers to the chemical reaction between carbon dioxide in the air and calcium hydroxide in the concrete, producing calcium carbonate and water. Carbonation reduces the alkalinity of the concrete. When the carbonation depth reaches the surface of the steel bars, it destroys the passive film on the surface of the steel bars, leaving the steel bars unprotected and more prone to corrosion. In addition, carbonation also leads to an increase in concrete shrinkage, causing cracks and reducing the strength and durability of the concrete.

Suggested Countermeasures

For prefabricated panel structure residences that show signs of steel bar corrosion and concrete carbonation, timely detection and assessment should be carried out, and corresponding repair and reinforcement measures should be taken according to the specific situation. For example, perform rust removal treatment on corroded steel bars and apply anti-rust coatings; repair or replace severely carbonated concrete; strengthen the overall integrity and stability of the structure and improve the seismic performance of the building to ensure the safety of residents' living.