Hangzhou Prefabricated Slab House Design

In the design of prefabricated slab houses in Hangzhou, the prefabricated concrete steel bar truss floor deck (non-removable formwork) system is a key technology with significant advantages and wide applications.

Technical Principles and Structural Features

This system involves pre-processing the steel bars in the floor slab into steel bar trusses in a factory and prefabricating them together with a fine aggregate concrete base plate through industrial means to form a non-removable formwork steel bar truss floor deck. During construction, the floor deck is directly laid on the beam surface system, and only necessary connecting structural steel bars (such as distribution bars and negative moment bars) need to be additionally arranged on site. Then, concrete is poured to form a complete reinforced concrete floor slab system. Its core structural features include:

• Factory-prefabricated Standardization: The steel bar trusses and base plates are integrally produced in the factory, ensuring high dimensional accuracy and strong quality controllability.
• Non-removable Formwork Design: The fine aggregate concrete base plate serves as a permanent formwork, eliminating the need for on-site removal and reducing construction procedures and construction waste.
• Optimized Load-bearing Performance: The steel bar trusses provide bidirectional load-bearing support and work in conjunction with the cast-in-place concrete, significantly enhancing the overall stiffness and load-bearing capacity of the floor slab.

Technical Advantages

1. High Construction Efficiency: The direct laying of the floor deck eliminates the need for traditional formwork erection and removal, shortening the construction period by approximately 30%-50%.
2. Stable Quality: Factory prefabrication avoids on-site manual operation errors, making it easier to control the concrete compactness and the thickness of the steel bar protective layer.
3. Green and Low-carbon: It reduces the consumption of formwork turnover materials and lowers construction noise and dust pollution, meeting the requirements for green building development in Hangzhou.
4. Good Economic Performance: The overall cost is approximately 15%-20% lower than that of traditional cast-in-place floor slabs, making it particularly suitable for large-scale residential construction.
5. Strong Decorative Adaptability: The floor slab has a high surface flatness and can be directly plastered and painted, meeting the needs of refined residential decoration.

Application Scope

This system is applicable to the design of residential floor slabs with various structural forms in Hangzhou:

• Steel Structure Residences: It works in conjunction with steel beams to solve the fire protection and sound insulation problems of steel structure floor slabs.
• Concrete Structure Residences: It replaces traditional wooden or aluminum formworks, improving construction efficiency and floor slab quality.
• Prefabricated Buildings: As part of prefabricated components, it is combined with prefabricated wall panels, stairs, etc., to achieve the goal of building industrialization.

Design Considerations

It is necessary to optimize the design of the floor deck connection joints in combination with the seismic fortification requirements (such as 6-degree or 7-degree fortification) and climatic characteristics (humid and rainy) in Hangzhou to ensure waterproofing and durability. At the same time, it should coordinate with the architectural and mechanical and electrical disciplines to reserve space for pipeline insertion and avoid damaging the structure through later slotting.