Safety Hazards of Prefabricated Houses
The safety hazards of prefabricated houses mainly include issues related to structural integrity and foundation, core components, unauthorized modifications and usage environments, as well as other aspects.
Structural Integrity and Foundation Issues: If problems arise with the foundation, there will be noticeable settlement marks around the house, with differences in elevation between indoor and outdoor floors. Slanting cracks may appear at the bottom of walls due to uneven foundation settlement. Additionally, the entire house may exhibit visible tilting or twisting phenomena. Poor foundation treatment and uneven settlement can be fatal to prefabricated houses, leading to tilting and cracking that are difficult to rectify.
Core Component Issues: Regarding prefabricated floor slabs, transverse through-cracks may appear at the bottom of the slabs, or significant cracking may occur at the joints between slabs. There may be noticeable downward bending or sinking in the middle of the slabs. At the positions where the prefabricated slabs rest on the walls, the concrete may be loose, crumbling, with exposed and rusted steel bars. Cracks, both vertical and diagonal, may appear on load-bearing walls, or cracking and downward deformation may occur above door and window openings on lintels. At the base of walls on the ground floor, bricks or masonry may be severely weathered, flaking, or crumbling. For three-story or higher brick-and-concrete prefabricated slab houses, if ring beams and structural columns are not installed, the overall seismic resistance and safety will be significantly compromised. In terms of node connections, the support of prefabricated slabs on walls may be insecure, showing signs of looseness, with detachment or cracking at wall corners and intersections.
Unauthorized Modifications and Usage Environment Issues: Unauthorized modifications to load-bearing walls, such as removing load-bearing walls without permission, opening door and window openings in load-bearing walls, or enlarging opening sizes; unauthorized additions (increased loads), such as privately adding floors on rooftops, adding mezzanines, or stacking heavy items on floor slabs; changing the purpose, such as converting a house originally designed as a residence into a densely populated business premises, significantly increasing live loads and easily triggering safety accidents.
Other Issues: The house has low structural strength and is not earthquake-resistant; it has a short service life, with high repair difficulty and cost; wall cracks and susceptibility to water leakage; poor thermal insulation, being cold in winter and hot in summer; in terms of construction height, the higher the house, the greater the load borne by the prefabricated parts at the bottom. If the bottom is not reinforced, it is easily crushed, triggering continuous collapses; if the joints of prefabricated拼接 (here it should be 'prefabricated components') are not properly treated, water leakage problems will persist, affecting both the roof and walls.
