Prefabricated Panel House Materials
The main materials for prefabricated panel houses include cement, steel bars, lightweight aggregates, and auxiliary materials such as additives and waterproofing agents. These materials, through scientific proportioning and process combination, jointly endow the prefabricated panels with structural strength, durability, and construction convenience.
Cement is the core binding material for prefabricated panels. As an inorganic cementitious material, cement undergoes a hydration reaction when mixed with water, forming a hardened mass with binding ability that firmly combines steel bars and aggregates. Ordinary Portland cement, due to its high early strength and good durability, has become the mainstream choice for prefabricated panel production. The strength grade of cement directly affects the compressive strength of the prefabricated panels. For example, cement with a grade of C30 or above can meet the load-bearing requirements of residential floor slabs. The hardened cement matrix can also effectively resist environmental erosion, ensuring the stability of the prefabricated panels in humid or freeze-thaw environments.
Steel bars are the key materials for enhancing the mechanical properties of prefabricated panels. Hot-rolled ribbed steel bars or threaded steel bars are commonly used, and the raised ribs on their surfaces significantly improve the bonding force with the cement matrix. After precise calculation of the reinforcement ratio, the steel bars are arranged inside the prefabricated panels to form a load-bearing framework. When the prefabricated panels bear loads, the steel bars bear tensile stress, while the cement matrix bears compressive stress. The two work together to prevent structural deformation or fracture. For example, 8mm-diameter HRB400-grade steel bars can have a reinforcement spacing of 150-200mm in common floor slabs, meeting load-bearing requirements while controlling costs.
The application of lightweight aggregates optimizes the physical properties of prefabricated panels. Materials such as polystyrene foam particles and expanded perlite, by partially replacing traditional aggregates, can reduce the self-weight of the prefabricated panels by 20%-30%. This not only reduces the difficulty of transportation and hoisting but also lowers the overall load of the building, making it particularly suitable for sites with low foundation bearing capacity. The porous structure of lightweight aggregates also improves the thermal insulation performance of the prefabricated panels. For example, a prefabricated panel containing 15% expanded perlite can have a thermal conductivity of less than 0.2W/(m·K).
Auxiliary materials such as additives and waterproofing agents further enhance the comprehensive performance of prefabricated panels. Water reducers can reduce water consumption by 10%-15%, improving the concrete density while maintaining workability. Air-entraining agents can introduce uniformly distributed tiny bubbles, enhancing freeze-thaw resistance. Waterproofing agents, through chemical reactions or physical barrier mechanisms, reduce the water absorption rate of the prefabricated panels to below 5%, effectively preventing leakage problems. These materials are usually added at a proportion of 0.5%-2% and must strictly follow the mix design requirements.
