Safety of Prefabricated Panel Houses
There are many hidden dangers in the safety of prefabricated panel houses, and their overall safety is relatively low, requiring caution.
Poor Earthquake Resistance
Prefabricated panel houses have poor integrity, similar to being built with building blocks. The various parts lack firm steel bar connections, making it difficult to form an overall structure. When encountering earthquakes or shaking, the floor slabs and walls are highly likely to separate instantly and collapse suddenly, without any time for crack warnings or deformation buffering. In earthquakes, the collapse of such houses is severe, resulting in a high casualty rate.
Vulnerable Connection Points
The connections between prefabricated panels and walls are mostly simple overlaps, and the connections between panels are simply filled with seams, lacking rigid frame structures such as ring beams and structural columns. When the foundation settles or the walls crack, the prefabricated panels will shift and loosen. Over time, the connection points will weather, the steel bars will rust, and their strength will gradually decrease, potentially triggering a chain collapse accident.
Material Issues
The steel bars used in regular prefabricated panels are relatively thin. However, some small workshops, in pursuit of profit, use thin steel wires instead of steel bars, and the concrete grades do not meet the standards and the thickness is insufficient, resulting in reduced material quality and lack of quality assurance. Prefabricated panels are brittle. Once their load-bearing capacity is exceeded, they will break instantly without any warning. Daily situations such as stacking heavy objects, renovating and hitting the floor, and the aging of the house over time may all cause sudden collapses.
Crack Issues
Prefabricated panels are most prone to cracking at the joints, especially in large-span areas such as the center of the living room. Rusty steel bars become brittle, just like a rusty clothes hanger, and can break with a little force.
Other Hidden Dangers
- Floor Slab Issues: There may be cracks at the bottom of the slabs, deflection and deformation, etc. At the positions where the prefabricated panels are placed on the walls, the concrete is prone to loosening and dropping debris, and the steel bars are exposed and rusted.
- Load-Bearing Wall Issues: Load-bearing walls may have vertical cracks, diagonal cracks, etc. The lintels above door and window openings may crack and deform under pressure. The bricks or masonry at the bottom of the walls on the ground floor may severely weather, peel off, and become loose. If brick-concrete prefabricated panel houses of three stories or more do not have ring beams and structural columns, their overall earthquake resistance and safety will be greatly reduced.
- Node Connection Issues: The supports of the prefabricated panels on the walls may not be firm, showing signs of looseness. The corners and intersections of the walls may separate or have cracks.
- Illegal Renovation and Usage Environment Issues: Later improper renovations, such as removing or altering load-bearing walls, illegal additions (increasing the load), and changing the purpose, will greatly increase the safety hazards of the house.
