Reinforcement Drawing of Prefabricated Concrete House

The reinforcement drawing of a prefabricated concrete house should be designed with reference to standard drawing collections or technical specifications, taking into account the specific types of components. Currently, there is no unified complete example for residential buildings, but the key points for reinforcement of common components are as follows:

1. Reinforcement of the bottom plate of laminated slabs
According to the drawing collection of the standard bottom plate for prestressed concrete steel tube truss laminated slabs (part of the series of standard prefabricated concrete components for assembled residential buildings in Sichuan Province), the reinforcement drawing of the bottom plate of laminated slabs should clearly specify the arrangement of steel bars. Key parameters include the diameter, spacing, anchorage length, and position of prestressed bars of the steel bars. For example, the bottom plate may adopt a two-way stressed steel bar mesh, and the spacing of the steel bars should meet the requirements for the load-bearing capacity and crack control of the floor slab. The reinforcement drawing should be used in conjunction with the component template drawing, which indicates the external dimensions of the bottom plate (such as length, width, and thickness) and the positions of embedded parts, but does not directly reflect the arrangement of steel bars.

2. Reinforcement of prefabricated bent frames columns
The reinforcement drawing of columns in a reinforced concrete prefabricated bent frames factory building usually divides the cross-sections according to different parts of the columns (upper column, corbel, column body, and column base) and indicates the following information:

• Stirrup number: Specify the type (such as rectangular or spiral stirrups), diameter, and spacing of the stirrups. For example, the column base may adopt densified stirrups to improve shear resistance.
• Longitudinal steel bar number: Indicate the quantity, diameter, and arrangement of the main steel bars. For example, the column body may be equipped with symmetrically distributed longitudinal steel bars to withstand axial forces.
• Tie bar number: Used to fix the relative positions of stirrups and longitudinal steel bars to prevent displacement of the steel bars.
  All information about the steel bars (grade, diameter, quantity, shape, and detailed dimensions) should be listed in the Steel Bar Table and used in conjunction with the Column Template Drawing, which shows the height of the column, changes in cross-sections, the position of the corbel, and the arrangement of embedded parts, etc.

3. Reinforcement of the steel bar truss floor deck system
The reinforcement characteristic of the prefabricated concrete steel bar truss floor deck system is that the steel bar truss has been processed during factory prefabrication and can be directly used as the stressed steel bars during the service stage of the floor slab. Its reinforcement should comply with standards such as the Technical Specification for the Application of Steel Bar Truss Floor Decks (T/CECS 1069-2022). The concrete non-removable bottom formwork and the steel bar truss work together to bear the load, and it is necessary to ensure that the spacing, height, and connection method of the steel bar truss meet the design requirements. For example, the upper chord steel bars of the truss may serve as negative moment steel bars, the lower chord steel bars as positive moment steel bars, and the web steel bars provide diagonal support.

Design Recommendations
Since the reinforcement of a prefabricated concrete house needs to be customized according to the specific types of components, load conditions, and regulatory requirements, it is recommended to refer to the reinforcement design requirements in corresponding standard drawing collections (such as special drawing collections for laminated slabs, stairs, bent frames columns, etc.) or technical specifications, and have detailed calculations and drawings completed by professional structural engineers.