First, the types of scaffolding commonly used on construction sites
(i) Ground-type scaffolding
(ii) Door-type scaffolding
(iii) Bowl-type scaffolding
(iv) Socket-type scaffolding
(v) Full-floor scaffolding
(vi) Cantilever scaffolding
(vii) Attached lifting scaffolding (commonly used in high-rise buildings, especially super-high-rise buildings)
(viii) High-altitude working hanging basket
Second, ground-type scaffolding:
1. Before the scaffolding is erected, a special construction plan and safety technical measures should be prepared. After the scaffolding is erected, it must be inspected and accepted before it can be put into use.
2. Floor-mounted scaffolding can be divided into bamboo scaffolding (prohibited from use), wooden scaffolding and fastener-type steel pipe and fastener scaffolding according to material; it can be divided into masonry frame and decoration frame according to use function; it can be divided into single-row and double-row scaffolding, inner scaffolding, and outer scaffolding, full-height frame, ramp, horse, etc. according to structure; it can be divided into three types according to frame shape: straight type; open type; closed type.
(1) Single-row scaffolding is not suitable for the following situations:
1) Single-row scaffolding shall not be used if the building height exceeds 24m.
2) The horizontal bars of the single-row scaffolding should not be set in the following locations:
① Locations where scaffolding eyes are not allowed in the design;
②) The triangle range of 60° between the lintel and the two ends of the lintel and the height range of 1/2 of the clear span of the lintel;
③ Window walls with a width of less than 1m;
④ Within the range of 500mm on each side of the beam or under the beam;
⑤ Within the range of 200mm on both sides of the brickwork and door and window openings and 450mm at the corners, or within the range of 300mm on both sides of the door and window openings of other walls and 600mm at the corners;
⑥ Wall thickness is less than or equal to 180mm;
⑦ Lightweight walls such as independent or attached brick columns, hollow brick walls, aerated blocks, etc.;
⑧ Brick walls with masonry mortar strength less than or equal to M2.5.
(2) Classification of double-row ground-type scaffolding:
1) General type (the height of the frame is greater than 24m and not more than 40m;)
2) Super high type (the height of the frame is greater than 40m).
Third, material requirements
(1) Steel pipe: Generally, 48.3mmx3.6mm welded steel pipe or ф51mmx3mm seamless steel pipe is used. The material must comply with the provisions of Q235A grade steel. The weight of each steel pipe shall not exceed 25.8kg, and steel pipes of different diameters shall not be mixed; the steel pipe must be painted with anti-rust paint. When the degree of rust is greater than 0.5mm, the steel pipe reaches the scrap standard and shall not be used.
(2) Fasteners:
1) Cast iron components should be used, and the material must comply with the KTH330-80 forgeable cast iron casting standard.
2) The manufacturer’s production license, product certificate, and quality qualification certificate must be available.
3) Fasteners must not have cracks, bubbles, deformation, thread slip, etc., and should not have rust, sand holes, or other cast iron defects that affect the use function. Sand sticking, pouring risers, residual burrs, oxide scale, etc. that affect the appearance quality should be cleaned up.
4) The fastener and the steel pipe should fit tightly together and have a good bond when fastened to the steel pipe. When the screw tightening torque reaches 65N·m, the fastener shall not break.
5) The surface of the fastener shall be treated with rust prevention.
(3) Scaffolding
1) The thickness of the bamboo scaffolding shall not be less than 5cm, the length shall be 3.2m, and the width shall be 30cm. The bamboo pieces shall be connected into a whole by tensioning screws not larger than 10mm at 100mm at both ends and every 500mm in the middle. The bolts must be tightened.
2) The wooden scaffolding shall be made of fir or red pine boards with a thickness of not less than 5cm, a width of 20~30cm, and a length of 4~5m. The material shall be one material. A 4mm galvanized steel wire hoop shall be wrapped around 2~3 times at 8cm at both ends of the scaffolding, or nailed with iron sheets. Scaffolding boards that are rusted, twisted, cracked, broken, or have large knots shall not be used.
3) Steel scaffolding boards should be made of 2~3mm thick Grade I steel, 1.3~3.6m long, 23~25cm wide, 3~5cm high, with connection devices at both ends and anti-slip holes drilled on the board surface. Cracked and twisted scaffolding boards shall not be used.
Fourth, requirements for the erection of scaffolding poles
(1) The foundation must meet the load requirements of the entire scaffolding frame and be 50mm~100m above the natural ground. Drainage measures should be taken around it.
(2) A pole pad should be placed on the upper part of the foundation, which should be more than 50mm above the foundation; when using a wooden pad, a metal base must be added.
(3) The step distance of the scaffolding bottom layer shall not exceed 2 meters, and the poles must be reliably connected to the building structure with wall connecting rods.
(4) For the extension of vertical poles, except for the top step of the top floor, which can be overlapped, the joints of other parts must be connected by butt fasteners. The specific regulations are as follows: The butt fasteners on the vertical poles should be staggered, and the joints of two adjacent vertical poles should not be set in the same direction. The two joints separated by one vertical pole should be staggered in height by no less than 500m, and the distance from the center of each joint to the main node should not be greater than 1/3 of the step.
(5) The top of the vertical pole should be no less than 1m above the parapet skin and 1.5m above the eaves.
Post time: Nov-26-2024