Prefabricated Three-Story House
The construction speed, structural materials, prices, and accident cases of prefabricated three-story houses are as follows:
Construction Speed: The construction speed of prefabricated three-story houses is relatively fast. At a construction site in Qixian, Henan, the main structure of a three-story villa made of prefabricated concrete houses was installed in just 4 hours, and a 100㎡ house could be ready for occupancy in only 5 days from an empty lot. Additionally, some prefabricated houses can complete the main structure of a three-story building in 14 days. Factors such as different construction conditions, house sizes, and designs can lead to variations in construction time. However, overall, compared to traditional construction methods, prefabricated houses have a significant advantage in construction speed, greatly shortening the construction period and improving construction efficiency.
Structure and Materials: In terms of structure, most prefabricated three-story houses adopt a full-frame shear wall structure. For example, they use C35 concrete paired with Φ14 threaded steel bars, with a single-module reinforcement ratio of 1.2%. The wall thickness is 200mm, and the compressive strength reaches 30MPa, equivalent to being able to withstand 3,000 tons per square meter, indicating high structural strength. The connection methods between modules are diverse and robust, combining pre-stressed bolts (with a tensile strength of 25 tons) with traditional Chinese mortise-and-tenon joints from ancient architecture. In a simulated Wenchuan earthquake test, the overall displacement was only 3cm under a 9-degree intensity shake, demonstrating good seismic performance. Regarding material usage, some prefabricated houses lay plastic sheets on the foundation to lock in concrete moisture. The load-bearing columns and beams use mortise-and-tenon joints with precisely fitting protrusions and recesses, secured with nuts. The gaps are filled with expanding foam, the nut areas are sealed with cement, and after backfilling with soil, a 10cm-thick foam board is laid, followed by secondary concrete pouring with steel bars, further enhancing the stability and durability of the house.
Price: The prices of three-story prefabricated houses vary by region, brand, and configuration. For example, a three-story light steel house assembled from prefabricated拼接 (should be 'prefabricated modular') components for rural use in Cangzhou, Hebei, costs 480.00 yuan per square meter. A prefabricated integrated bathroom with a shower unit in Linyi, Shandong, costs 2,500.00 yuan per set. Prices are influenced by various factors, such as material quality, the complexity of house design, and construction techniques.
Accident Case: On April 11, 2024, an accident occurred in a three-story prefabricated slab house in Fengshouchang, Guanba Town, Zhongxian County, Chongqing. The temporary accumulation of excessive load on the second-floor slab exceeded the bearing capacity of the prefabricated slab, causing brittle fracture and collapse of the slab, resulting in 2 deaths and 3 injuries. This reminds us to strictly follow design requirements when using prefabricated houses and avoid overloading and other situations.
