Prefabrication Construction of Factory Building Roof Truss Beams
The prefabrication construction of factory building roof truss beams adopts the method of factory prefabrication and on-site hoisting, which offers advantages such as saving space and improving mold utilization. During construction, it is necessary to make good preparations in terms of technology, personnel, and equipment, follow regulations, and pay attention to the limitations of stacked prefabrication.
Construction Preparation:
In terms of technical preparation, it is required to organize drawing review sessions to familiarize with the structural form and dimensional parameters of the roof truss beams, prepare hoisting construction plans and organize expert demonstrations, verify factory quality certificates such as concrete strength reports and steel bar retest reports, and use measuring instruments to accurately measure and set out the hoisting operation area. For personnel preparation, a special management team should be established to be responsible for overall management, technical guidance, and safety supervision. Hoisting operators should possess special operation certificates and have rich experience, and sufficient auxiliary personnel should be equipped with clearly defined responsibilities. Equipment preparation involves selecting appropriate hoisting equipment, such as truck cranes, based on the weight and span of the roof truss beams as well as the on-site working space, and conducting a comprehensive inspection of their performance.
Production Process:
The production process in the prefabricated beam yard includes standardized procedures such as steel bar processing, steel bar binding, formwork installation and adjustment, and concrete pouring. Modern prefabricated beam production introduces intelligent circular production lines and digital twin technology to achieve full-process automation, such as using mobile pedestals, hydraulic formworks, intelligent vibration systems, and steam curing processes to improve production efficiency and quality.
Limitations of Stacked Prefabrication:
When using the stacked method to produce prefabricated roof truss beams, it is generally recommended to stack a maximum of 3 - 4 layers. If more than 4 layers are stacked, the load borne by the bottom components increases sharply, and the risks of component deformation and adhesion increase significantly, while also imposing extremely high requirements on the hoisting process. The specific number of layers should be determined through calculations based on parameters such as the self-weight of the components, concrete strength grade, formwork stiffness, standard value of foundation bearing capacity, and component shape.
Industry Regulations and Standards:
Throughout the construction process, industry regulations such as the Technical Specification for Construction Process of Building Engineering should be followed, and hoisting operations should comply with standards such as the Technical Specification for Safety of Hoisting Engineering in Building Construction (JGJ276 - 2012) to ensure construction safety and quality. For example, the Beian Depot project of Qingdao Metro Line 7 adopted the assembled construction method of "factory prefabrication + on-site assembly" and completed the precise hoisting of the first prefabricated beam, providing practical reference for the prefabrication construction of factory building roof truss beams.
