Prefabricated House Frame Beam

The prefabrication of house frame beams is a crucial step in prefabricated concrete frame structures, with core processes including design preparation, mold making, steel bar processing and binding, concrete pouring and vibration, and demolding and transportation.

1. Design Preparation
   It is necessary to clarify the dimensions, shapes, and steel bar configuration requirements of the prefabricated beams based on the design drawings, and complete technical disclosures and process planning. For example, the Qingdao Metro Line 7 project optimized design parameters using BIM technology to ensure precise alignment between the prefabricated beams and on-site assembly. This stage strictly adheres to the load calculation specifications in the Technical Standard for Prestressed Prefabricated Concrete Frame Structures (JGJ/T502-2024).

2. Mold Making
   Molds should be selected as steel or wooden molds based on project requirements, with priority given to steel molds reinforced with 5mm-thick steel plates to enhance reusability. For instance, the Shanmei Expressway project achieved uniform and dense concrete in box girder prefabrication by arranging external vibrators on the side molds. Mold design should include provisions for demolding slopes and positioning pins to ensure assembly accuracy over multiple uses.

3. Steel Bar Processing and Binding
   Steel bars undergo cutting, bending, and welding processes, with intelligent circular production lines enabling automated processing and an error margin controlled within ±2mm. During binding, guide bar clips are used to fix spacing, and magnetic positioning plates control the thickness of the protective layer. Some projects have introduced robotic welding technology to enhance joint connection strength.

4. Concrete Pouring and Vibration
   Ready-mixed concrete is poured in layers, complemented by intelligent vibration systems or immersion vibrators to eliminate air bubbles. For example, the Qingdao Metro project increased concrete density to over 98% using a high-frequency vibration table. Steam curing technology can shorten the cycle to 1 day, but the temperature gradient must be controlled at ≤15℃/h to prevent cracking.

5. Demolding and Transportation
   Demolding can only occur after the curing strength reaches 75% of the design value, using specialized lifting devices to avoid surface damage. During transportation, the beams must be secured on specialized trailers with shock absorption devices. For example, the first lifting piece of Qingdao Metro Line 7 adopted a 'factory prefabrication + on-site assembly' model, improving transportation efficiency for single beams by 40%.

Technical Characteristics:

• Standardized Production: Adheres to JGJ/T502-2024 specifications, with digital twin technology enabling full-process automated monitoring.
• Material Innovation: LUHPC material achieves a compressive strength of 150MPa, with durability increased by three times.
• Green Sustainability: Microalgae carbon fixation technology absorbs CO₂ generated by concrete carbonation, enabling waste gas resource utilization.