The outer frame is at the top, out of the roof, why pull the wall?

Because if the wall part is not set up enough or not set up in time after demolition, it is easy to cause scaffolding collapse accidents.

Section 6.4 of the Technical Code for Safety of Fastening Steel Pipe Scaffolding in Building Construction (JGJ130-2011) stipulates the specification requirements and characteristics of underground diaphragm wall components, which must be able to withstand tension and pressure. Double-row scaffolding with a height of more than 24m should be connected to the building with rigid diaphragm wall. At present, it is convenient to use fasteners to connect the scaffold wall in China. Scaffolding specification stipulates that the design value of anti-sliding bearing capacity of a single fastener is 8kN. Embedded steel pipe method is the most commonly used connection method of wall parts at present, which can play the role of rigid connection. Embedded steel pipe method is to use a vertical short steel pipe to bury the beam about 20cm before concrete pouring, exposing the back of the beam about 20cm. After concrete pouring is completed, connect the vertical pole and the vertical short steel pipe with horizontal steel pipe. The traditional method of connecting wall parts is to fix the connecting wall steel pipe directly through the wall and into the room. After the scaffolding is removed, many holes will be left. When filling holes later, it is necessary to carry out oxygen welding and gas cutting on embedded steel pipes and fasteners. It is not only a waste of materials, but also time-consuming and laborious. The new scaffold wall-connected parts solve the shortcomings of traditional wall-connected parts, and adopt the way of beam side embedding, which is not only convenient to disassemble and assemble, but also reusable without any damage to the wall surface. The labor and cost of repairing holes are saved, and the hidden danger of water seepage is eliminated. The new scaffold wall-connected parts are composed of special plastic pipes embedded with square steel nuts, steel pipes with round steel nuts and stud bolts, which are safe and reliable.