Fracture of House Prefabricated Slab

At around 12:00 on April 11, 2024, a house prefabricated slab fracture accident occurred in Fengshou Community, Guanba Town, Zhong County, Chongqing, resulting in 2 deaths and 3 injuries.

Accident Causes

After on-site investigation by experts, it was preliminarily determined that the accident was caused by excessive temporary stacking loads on the second-floor slab, which exceeded the bearing capacity of the prefabricated slab, leading to brittle fracture and falling of the slab. The building involved in the accident was a three-story prefabricated slab house, with a mahjong parlor on the ground floor and a warehouse for storing goods on the second floor. There were five or six people in the house when the accident occurred. As a concrete prefabricated component, the bearing capacity of the prefabricated slab is clearly defined during design. Overloading will directly damage the structural stability and trigger the risk of fracture.

Characteristics and Hidden Dangers of Prefabricated Slabs

Prefabricated slabs are concrete prefabricated components produced and processed using cement, steel bars, etc., and are directly transported to the construction site for installation. Their advantage lies in high construction efficiency, but they have inherent defects:

1. Poor integrity: Prefabricated slabs are connected by splicing, and their earthquake resistance and deformation resistance are weaker than those of cast-in-place reinforced concrete structures;
2. Limited bearing capacity: The load must be strictly calculated during design. If it is overloaded for a long time (such as stacking heavy objects or adding floors through renovation), it will accelerate structural fatigue;
3. Insufficient durability: Cement and steel bars may experience performance degradation due to environmental erosion (such as moisture and corrosive gases) during long-term use, reducing the bearing capacity.

Common Causes of House Damage

In addition to overloading, the following factors may also cause damage to prefabricated slabs during the long-term use of houses:

1. Natural aging: The material properties decay over time, especially for houses that are not regularly maintained;
2. House renovation: Unauthorized removal of load-bearing walls, making holes, and other actions will damage the structural force system;
3. Impact of adjacent construction: Vibrations from pile driving and excavation at nearby construction sites may cause house settlement or cracks;
4. Design defects: Early prefabricated slab houses may have problems such as low design standards and poor construction quality control.

This accident serves as a warning: Prefabricated slab houses need to undergo regular structural safety inspections to avoid overloading or arbitrary renovation. If cracks, deformations, or other abnormalities are found, use should be stopped immediately, and a professional institution should be contacted for evaluation.