System, anti-falling system, synchronous load control system and other auxiliary systems. As shown in figure 2- 1 1.
I. Vertical main frame
The vertical main frame is an important load-bearing mechanism connected with the auxiliary supporting structure, which undertakes and transmits vertical and horizontal loads.
It not only bears the downward construction load, but also has a large horizontal force. Therefore, there must be enough
The spatial stiffness of scaffolding can meet the good stress state of scaffolding in construction. The vertical main frame consists of external vertical poles and horizontal poles.
Rod, corridor diagonal rod and guide rail inner rod; The main forms are plate frame, lattice guide rail combination frame and so on. be listed
Similarly, the main frame is designed as a special-shaped space welded frame, and its standard section height is 1.8m, which is used at the end of each special-shaped space truss.
Flanged connection. Special-shaped welded joint combined structure is adopted, which is convenient for installation, transportation and storage, as well as installation and attachment.
Connecting, lifting and safety devices. draw
Second, the horizontal support truss
The horizontal support truss takes the vertical main frame as the bearing support, its two ends are connected with the node plate of the vertical main frame, and its upper part is connected with the steel pipe of the operation frame. The horizontal support truss consists of a middle frame, a cross bar and a diagonal bar. Generally, 48mm×3.5mm steel pipes are used and welded plates are bolted for assembly.
When the truss beam structure assembled by foot bars is adopted and connected with the operating frame into a whole, it can be called "bottom structural beam"
Framework "; When the fixed welded truss structure is adopted, it can be called "bottom truss" or "bottom frame". In recent years, the main progress in the design of frame bottom structure is: the beam frame of frame bottom structure has tended to be finalized; In order to ensure construction safety and convenient operation, a truss (frame) frame with fixed welded structure (steel or steel pipe) was tried out. The bottom truss (frame) frame is composed of two pieces, each member is welded to ensure greater stiffness of the joint, and the connection between the two pieces is flexible bolts to facilitate on-site assembly. The horizontal truss is connected with the vertical main frame through a rotatable hinge, which eliminates the secondary stress generated in the process of scaffold stress and makes it more reasonable. In addition, in order to solve the hanging problem of cantilever section, diagonal tie rods can be symmetrically arranged on the main frame in groups. The load from the upper frame is transferred to the vertical main frame through diagonal braces, which can greatly improve the stress condition of the horizontal support structure, virtually reduce the span of the horizontal support structure and effectively reduce its deflection.
Third, the frame structure
Frame structure refers to the part between the vertical main frames and above the horizontal supporting truss, including the inner and outer rows of uprights and feet.
Plate, connecting rod. In the process of construction, the frame members bear the construction load and transfer it to the horizontal supporting truss and the vertical main frame. A traditional attached lifting scaffold is equipped with scissors in the inner and outer rows to enhance the rigidity of the frame, which is also a part of the frame structure.
Fourth, the fall prevention system.
Overturning and falling is the "killer" that leads to safety accidents in the construction of attached lifting scaffolding. From the stress of scaffolding, overturning resistance is to solve the stability problem of scaffolding from the horizontal constraint. During construction, scaffolding should not be tilted in principle, and the overall scaffolding should keep a certain distance from the building to ensure smooth operation. However, in actual construction, the load unevenness of scaffolding in South China is generally eccentric, including front and back eccentricity and left and right eccentricity, especially in the construction of super high-rise structures. There are many uncertain factors in scaffold construction, and there are even potential safety hazards in high-rise or super-high-rise construction. Therefore, the scaffold system must be equipped with anti-falling devices, and it is not appropriate to combine the anti-falling devices with the attachment and support devices of the lifting frame. These two devices act on the same structure, which easily leads to the failure of the anti-fall system.
According to the different trigger modes, fall arresters can be divided into two types: speed trigger and spring tension trigger.