For the steel pipes of the fastener-type steel pipe scaffolding, it is advisable to use steel pipes with an outer diameter of 48.3±0.36mm and without serious corrosion, bending, flattening, or cracks. A special construction plan should be prepared for the erection of the frame, and the structural design should be calculated reviewed, and approved by regulations. For ground-type steel pipe scaffolding with a height of 24m or above, a special safety construction plan must be prepared before construction. When the frame is erected beyond the height allowed by the specification (the erection height exceeds 50m, experts should be organized to demonstrate the special construction plan. The erection height of a single-row scaffolding shall not exceed 20m general terms), steel pipes of different specifications shall not be mixed.
1. Foundation treatment of ground-type scaffolding
(1) The foundation of the erection frame must be flat and solid, with sufficient bearing capacity; there must be no water accumulation in the erection site.
(2) During the erection, drainage ditches or other drainage measures should be set up on the outside and periphery of the scaffolding.
(3) The support pole pads should meet the bearing capacity requirements, and the pad thickness should not be less than 50mm.
(4) The support pole pads should meet the bearing capacity requirements, and the bottom elevation of the base should be 50~100mm higher than the natural floor.
2. Sweeping rods for ground-type scaffolding
The frame must be equipped with longitudinal and transverse sweeping rods. The longitudinal sweeping rod must be fixed on the pole no more than 200mm from the bottom end of the steel pipe with right-angle fasteners. The transverse sweeping rod must be fixed on the pole close to the bottom of the longitudinal sweeping rod with right-angle fasteners.
3. Wall ties for ground-type scaffolding
The wall ties should be arranged close to the main node and the distance from the main node should not be greater than 300mm. The wall ties of double-row steel pipe scaffolding should be connected to the inner and outer rows of poles.
For double-row scaffolding with a height of more than 24m, rigid wall ties are also used to reliably connect with the building structure. The vertical spacing of the wall ties should not be greater than the floor height of the building, and should not be greater than 4m, and the horizontal distance should not exceed 6m. Wall ties must be set at both ends of the open double-row scaffolding.
Scissor braces and wall ties must be erected and dismantled simultaneously with the external scaffolding. It is strictly forbidden to erect them later or dismantle them first.
4. Scissor braces of ground-type scaffolding
Scaffolding should be continuously set up on the entire facade of the outside. The span of the scissor brace is 5 to 7 vertical poles. The extension of the diagonal rod of the scissor brace can be achieved by butt joint or overlap. The overlap length should not be less than 1m, and it should be fixed with no less than 3 rotating fasteners. For external frames below 24m, scissor braces are set up on the outer ends of the wall, corners, and vertical surfaces with a spacing of no more than 15m in the middle. For frames above 24m, continuous scissor braces must be set up on the outside.
The scissor brace and the vertical pole should be firmly connected to form a whole. The bottom end of the scissor brace rod should be tightly against the ground, and the angle of the scissor brace should be between 45” and -60”. Horizontal diagonal braces must be set up at both ends of the open scaffolding.
Horizontal diagonal braces must be set at both ends of the straight-line and open-type double-row scaffolding. For frames above 24m, a horizontal diagonal brace should be set at the corners of the frame and every six spans in the middle; the horizontal diagonal braces should be arranged in a zigzag shape from bottom to top in the same interval, and the diagonal braces should be crossed and connected to the top with the inner and outer large cross bars.
5. Working layer and safety protection of ground-type scaffolding
The scaffolding board (bamboo fence, iron fence) of the working layer should be full, precise, stable, and solid, and should not be more than 200m away from the wall. There should be no space, probe board, or flying board. The scaffolding board should be set on no less than three horizontal bars. When the length of the scaffolding board is less than 2m, two horizontal bars can be used for support. The two ends of the scaffolding board should be reliably fixed with the horizontal bars to prevent tipping.
A guardrail and a footboard not less than 180mm high should be installed on the outside of the operating surface.
The frame must be closed with a dense safety net sliding on the inside of the outer frame. The safety nets must be firmly connected, tightly closed, and fixed to the frame.
A horizontal safety net must be installed within a clearance distance of 3m below the operating surface of the scaffolding construction layer. A horizontal safety net should be installed every 10m or less below the first horizontal net. Horizontal safety nets should also be used for protection between the frame and the structure, and all safety nets must be tied with special ropes.
Post time: Oct-25-2024