Scaffolding is a commonly used temporary support structure in construction projects, consisting of steel pipes (48.3 * 3.6), fasteners, scaffolding, adjustable supports, and cantilever scaffolding made of steel. It is used to provide a convenient and safe working platform during the construction process, providing conditions for construction workers to stand, work, transport, and also facilitating equipment installation, material transportation, and other work. Therefore, scaffolding plays an irreplaceable role in construction projects..
After the completion of the foundation, before the installation of the frame;.
After the completion of the first step of setting up the large crossbar for large and medium-sized scaffolding;.
After setting up a height of 6-8 meters;.
Before applying load on the work surface;.
After reaching the design height (each layer of scaffolding for structural construction shall undergo one acceptance);.
After encountering wind or heavy rain of level six or above, the frozen area will thaw;.
● Discontinue use for more than a month;.
Before demolition;.
The surface of the steel pipe should be straight and smooth, without cracks, scars, layering, misalignment, hard bending, burrs, indentations, deep slides, and severe rust, and drilling is strictly prohibited; Steel pipes must be coated with anti rust paint before use;.
● Outer diameter 48.3mm, allowable deviation ± 0.5mm; Wall thickness 3.6mm, allowable deviation ± 0.36, minimum wall thickness 3.24mm; Vernier caliper inspection;.
● Should have a production license, quality inspection report, product quality certificate, and retest report;.
Cracks, deformations, and bolt slippage are not allowed; The contact area between the fastener and the steel pipe should not have oxide skin; The moving parts should be able to rotate flexibly, and the gap between the two rotating surfaces of the rotating fastener should be less than 1mm; The surface of the fasteners should be treated with rust prevention;.
The tightening torque value of the fastener bolt should not be less than 40N · m and should not exceed 65N · m;.
The design value of the compressive bearing capacity of adjustable braces should not be less than 40kN. Should have a product quality certificate and quality inspection report;.
The outer diameter of the adjustable support screw shall not be less than 36mm, the length of the adjustable support screw and nut rotation shall not be less than 5 buckles, and the thickness of the nut shall not be less than 30mm. The length inserted into the upright pole shall not be less than 150mm. The thickness of the support plate shall not be less than 5mm, and the deformation shall not be less than 1mm. The welding between the screw and the support plate should be firm, and the weld height should not be less than 6mm;.
Jiuze Construction regards corporate culture as the foundation of strategic implementation, and adheres to the corporate mission of “people-oriented, pursuing excellence, sustainable development, and enriching employees” in the development process. With the corporate purpose of “helping to build a high-quality project for a harmonious society”, we promote customer-centric and striving oriented, achieving sustained, stable, and high-quality rapid growth of the enterprise, and achieving material and spiritual wealth of employees. The effective operation of Jiuze Construction Engineering’s management system and the improvement of the talent training center’s self-evaluation examination system rely on the system to better practice standards and improve management. We carve quality and quality with the spirit of craftsmanship, adhere to the corporate philosophy of “integrity, innovation, cooperation, and win-win”, and sincerely cooperate with friends from all walks of life to achieve mutual benefit and create a better future together. The safety education for the construction of the buckle type scaffolding should consist of a connecting plate welded to the upright pole, a horizontal pole end buckle joint, and a diagonal pole end buckle joint..
1. The height of the template support should not exceed 24m; When it exceeds 24m, it should be specially designed separately..
2. The template support should be selected with fixed length horizontal rods based on the construction plan, and the vertical rod segments, adjustable brackets, and adjustable bases should be combined and inserted according to the support height..
3. The diagonal or diagonal braces of the template support should meet the requirements:.
4. The first layer of scaffolding poles should be arranged in a staggered manner with different lengths of poles. The vertical distance between staggered poles should not be less than 500mm. When a pedestrian walkway is required, an adjustable base should be provided at the bottom of the poles..
5. The diagonal or diagonal braces of double row scaffolding should meet the following requirements:.
6. The hook of the steel scaffold board must be fully fastened to the horizontal pole, and the hook must be in a locked state. The scaffold board on the working layer should be fully laid;.
7. The external side of the scaffolding on the homework layer should be equipped with foot blocking boards and protective railings, and a dense safety net should be hung on the outer facade of the scaffolding..
8. When there is a large gap between the working layer of the scaffold and the outer side of the main structure, a cantilever tripod hanging on the connecting plate should be set up, and a scaffold board that can form a closed inner side of the scaffold should be laid..
9. Before the construction of template brackets and scaffolding, a special construction plan should be prepared according to the basic requirements of this regulation, based on the situation of the construction object, the bearing capacity of the foundation, and the installation height. It should be reviewed and approved before implementation..
10. Construction operators must undergo professional technical training and pass professional exams before being certified to work. Before setting up the template support and scaffolding, the construction management personnel should provide technical and safety operation instructions to the operators in accordance with the requirements of the special construction plan..
11. The quality of steel pipe supports and components entering the construction site should be rechecked before use..
12. Qualified components and parts that have been accepted should be classified and stacked according to their varieties and specifications, and should be labeled with quantity and specification tags for future use. The storage area for components should have smooth drainage and no accumulated water..
13. The construction site for template brackets and scaffolding must be flat, solid, and equipped with drainage measures..
14. Demolition work should follow the principle of first erecting and then dismantling, and then erecting and dismantling first. Starting from a high place, it should be carried out layer by layer downwards. It is strictly prohibited to demolish both the upper and lower layers at the same time, and throwing is strictly prohibited..
16. When dismantling scaffolding, a safety zone should be designated, warning signs should be set up, and a dedicated person should be assigned to supervise..
17. Before dismantling, tools, excess materials, and debris on the scaffolding should be cleaned..
1. The personnel responsible for setting up template supports and scaffolding should hold a certificate before taking up their posts..
2. Scaffolding workers should wear safety helmets, seat belts, and anti slip shoes correctly..
3. During the use of template brackets and scaffolding, it is not allowed to dismantle the structural members of the framework without authorization. If demolition is required, it must be reported to the technical director of the engineering project and the chief supervising engineer for approval, and prevention and control measures must be determined before implementation..
4. It is strictly prohibited to carry out excavation operations within the range affected by the excavation depth of template supports and scaffold foundations..
5. The dismantled support components should be safely transmitted to the ground and throwing is strictly prohibited..
6. When conducting electrical welding operations on scaffolding or template supports, fire prevention measures and dedicated personnel must be in place for supervision..
The content of this image and text has been compiled through comprehensive network information. If there is any infringement, please contact us to delete it. Do you still not understand the supervision of scaffolding acceptance? Learn these 48 acceptance criteria for cantilever load embedded parts. Raw material requirements: use a diameter ≥ Φ 20 round steel, the use of threaded steel is strictly prohibited, and the embedded length must meet the load requirements of the special plan;.
Incorrect practice of cantilever load embedded parts: It is strictly prohibited to weld and fix them in the later stage..
Incorrect practice of pre embedded wall components in scaffolding: The pre embedded components are installed on the structural beam surface, leaving a hidden leakage risk for external wall construction..
Requirements for elevator entrance protective fence: guardrail height ≥ 1.6m, vertical steel bar spacing ≤ 100mm, standard floor and warning signs at the top, 180mm high kickboard installed at the bottom, made of ≥ 9mm thick plywood, and low-voltage lighting must be installed on the inside of the elevator shaft..
Requirements for setting up staircase guardrails: detachable water pipe guardrails with a height of ≥ 1.2m shall be used; Stairs with a drop of more than 3m on the edge must have a net hanging and a 180mm high baseboard installed at the bottom. The baseboard should be made of plywood with a thickness of ≥ 9mm..
The length and width of the openings inside the floor are ≥ 400mm х 400mm enclosure protection requirement: Fix the opening with four point expansion screws Φ 6 @ 150 steel mesh, surface sealed with ≥ 10mm thick plywood, covered with 200mm pressed edges all around, and then sealed with mortar..
The length and width of the openings inside the floor are less than 400mm х 400mm enclosed protection requirement: 10mm thick plywood fixed, painted with eye-catching paint markings..
Requirements for setting up edge guardrails: detachable water pipe guardrails with a height of 1.2m should be used. After installation, safety nets should be hung for protection. A 180mm high kickboard should be installed at the bottom, and the kickboard should be made of plywood with a thickness of ≥ 9mm..
Requirements for the installation of foundation pit guardrails: A detachable water pipe guardrail with a height of 1.2m should be used, and a safety net should be hung for protection. A 180mm high kickboard should be installed at the bottom, and the kickboard should be made of plywood with a thickness of ≥ 9mm. It is recommended to use a concrete backflow kickboard..
The requirement for setting up guardrails that cannot be closed with plywood is to use detachable water pipe guardrails with a height of ≥ 1.2m; Beyond the edge, install a 180mm high skirting board at the bottom, which is made of ≥ 9mm thick plywood..
Requirements for the installation of cantilevered flat and inclined baffles: The material used is 10mm thick plywood, with double-layer hard sealing; It is prohibited to use transparent materials for sealing. The general contractor must provide a special plan, which can only be implemented after confirmation by the supervisor and Party A..
Wrong practice of double-layer protection: The double-layer protection did not use a hard seal and instead used bamboo poles instead of 10mm thick plywood. Scaffolding safety standard atlas, rich in graphics and text, detailed in content, listing correct installation requirements! Due to the limited length of the article, only partial content is displayed here. If you need a complete version, please feel free to contact me directly! The inner roll of the scaffold with a distance of 150mm from the wall… Click on the blue text above to follow and get you a free copy of premium materials.
Is it okay for the general contractor and subcontractors to come over in the midst of a 150mm distance between the scaffolding and the wall? Who will do it? How many times? Who will restore it? What price.
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52. Guidelines for interface management of general contracting projects, available for download. Ten key points for safety inspection of attached lifting scaffolding! Our company’s main business scope is the sales and leasing of climbing frames. The company adheres to the unwavering goal of “integrity-based, quality oriented development”, and always adheres to the service tenet of “quality first, reputation first, and safety first”. We welcome new and old customers to come and discuss cooperation!.
The copyright belongs to the original author and the original source. If the original copyright owner does not agree to reprint, please contact this official account in time so that this account can delete the work immediately. Do you know the key points of scaffolding construction? 1) Before binding the steel bars in the cantilever layer, first place the centerline of the steel foundation beam on the template according to the designed longitudinal distance..
2) Then fix the U-shaped anchor bolt components. Before pouring concrete on the cantilever floor of the I-beam, measure the position of the embedded U-shaped steel reinforcement pull ring with a ruler according to the layout plan of the cantilever I-beam, and mark it properly. Then fix the U-shaped steel reinforcement pull ring and two L=1500mm, HRB400 18 anti pull reinforced steel bars, fixed to the bottom reinforcement of the floor slab/beam; Three U-shaped anchor bolts are pre embedded on each centerline, and plastic tape is used to wrap the bolts above the surface of the board to prevent contamination of the U-shaped anchor bolts during concrete pouring..
1) Before placing the I-beam, first pull wires at both ends of the exterior facade to locate the upright position, to ensure that the upright is in a straight line. The length of the fixed section should not be less than 1.25 times the length of the cantilever section..
2) The cantilever beam must ensure sufficient anchoring strength and section buckling resistance, and the cantilever length should be determined according to the design. When the ordinary main beam is cantilever, the upright pole is directly supported on the cantilever beam, and the longitudinal spacing of the horizontal cantilever beam is the same as the longitudinal spacing of the upper scaffold upright pole;.
3) After the concrete pouring is completed and the strength is increased, the cantilever foundation beam is laid. The foundation beam is made of 18 # I-beam, and the entry and exit positions are corrected. Then, steel pads and double nuts are used to fix it;.
4) Thread the I-beam into the U-shaped steel reinforcement pull ring and use steel pressure plates and bolts to fix the gap between the embedded ring and the I-beam with wooden wedges to ensure the stability of the I-beam..
5) After fixing the I-beam, lay 18 # I-beam longitudinally along the vertical pole of the frame and weld it to fix it;.
6) If the I-beam needs to pass through the wall, a customized wooden box should be installed at the point where the I-beam passes through the wall, so that the I-beam can be recycled after the scaffold is removed;.
7) When the anchorage length of the I-beam at the corner of the building is insufficient, it is necessary to add an I-beam coupling beam and use steel wire ropes to unload the I-beam coupling beam. The end of the I-beam should be welded with steel reinforcement heads to prevent the upright pole from slipping..
8) At the external corners of the structural facade, welding is used to install I-beams. The specific installation location and size are detailed in the cantilever I-beam layout diagram, and the installation method is shown in the following figure:.
9) At local locations, the I-beam should be extended to ensure its anchoring length on the structure. The specific length and position of the I-beam can be found in the attached plan layout of the cantilever scaffold..
1) External corners of the building structure: The cantilever beams should be arranged in a fan-shaped manner. If the cantilever beams intersect at the external corners, the length of the extended end cannot be guaranteed. At the intersection, the cantilever beams on both sides should be welded to the external corners, with -200 × 200 × 10mm steel plates added on both sides. All contact points must be fully welded, and the height of the welding feet should not be less than 8mm, and there should be no air holes, slag inclusions, or missed welding; If there are too many steel bars in the external corners of the structure and holes cannot be left, measures such as setting up embedded parts and welding steel triangular frames can be taken..
2) Suspended structural parts: The support points of the cantilever beam should be set on the structural beam, and should not be set on the extended balcony or cantilever plate, otherwise reinforcement measures should be taken; The layout diagram of the cantilever beam at the cantilever structure is detailed in the following figure..
1) After the I-beam is laid and fixed on the steel foundation beam, the bottom upright pole is placed on the I-beam using a top support for welding, and then the upright pole is overlapped with the horizontal pole through socket joints; At the bottom layer, the spacing between long and short upright poles is set to ensure that the bearing points of the upper and lower upright poles are misaligned, no longer on the same horizontal plane, and vertical diagonal pull rods are set according to requirements;.
2) Adjust the height of the bottom upright pole and adjust the first horizontal pole at the bottom to the same elevation;.
3) Weld and fix the bottom of the upright pole to the I-beam, and then select the corresponding specifications of steel pedals for laying according to the longitudinal spacing of the upright pole;.
4) The upright pole should be connected by a dedicated sleeve socket and inserted with a pin. The first floor upright pole of the scaffold should be arranged in a staggered manner with different lengths of upright poles, and the vertical distance between staggered poles should not be less than 500mm. Requirements and precautions for the installation and installation of new type of buckle scaffolding. The new type of buckle scaffolding is one of the more advanced scaffolding at present, and it is a new type of scaffolding that replaces ordinary steel pipes, fasteners, and bowl buckles. The buckle type scaffolding plays an important role in modern architecture and is a major trend in the use of scaffolding on construction sites. Therefore, it is necessary to fully understand and recognize its installation and erection requirements..
When using a buckle type scaffold to set up a double row outer scaffold, the height should not exceed 24m. If it exceeds 24m, additional design calculations must be carried out. Users can choose the geometric dimensions of the frame according to their usage requirements. The step distance between adjacent horizontal poles should be 2m, the longitudinal distance between upright poles should be 1.5m or 1.8m, and should not exceed 2.1m. The transverse distance between upright poles should be 0.9m or 1.2m..
Pole: The bottom of the pole should be equipped with an adjustable base, and the first floor pole should be arranged in a staggered manner with different lengths of poles. The vertical distance between staggered poles should be greater than or equal to 500mm..
Diagonal rod or diagonal brace: A vertical diagonal rod should be installed on each layer of the frame with no more than 5 steps longitudinally along the outer side of the frame, or a fastener steel pipe diagonal brace should be installed on every 5 steps. A vertical diagonal rod should be installed on each layer of the end span horizontally..
Wall connection: The setting of the wall connection should meet the following requirements. The wall connection components must be rigid rods that can withstand tensile and compressive loads. The wall connection components should be perpendicular to the scaffolding and wall. The wall connection components on the same floor should be in the same plane, with a horizontal spacing of no more than 3 spans and a distance of no more than 300mm from the outer surface of the main structure..
(1) Internal support step distance requirement: When the installation height does not exceed 8 meters, the step distance should not exceed 1.5m. When the installation height exceeds 8 meters, the step distance should not exceed 1.5m..
(2) Independent high support formwork height requirement: For elongated independent high support formwork frames, the ratio H/B of the total height of the frame to the width of the frame should not be greater than 3..
(3) Adjustable bracket requirements: The exposed length of the screw of the adjustable bracket shall not exceed 400mm, and the length of the bracket inserted into the upright pole or double channel steel beam shall not be less than 150mm..
(4) Adjustable base requirements: The exposed length of the adjustable screw rod on the adjustable base should not exceed 300mm, and the height of the bottom horizontal rod of the sweeping rod from the ground should not exceed 550mm..
(5) The continuous erection height requirement for double row external scaffolding should not exceed 24 meters..
(6) The step distance and span requirements for the double row external scaffold: the step distance should be 2m, the longitudinal distance of the upright pole should be 1.5m or 1.8m, and should not exceed 2.1m. The transverse distance of the upright pole should be 0.9m or 1.2m..
(7) Requirements for the arrangement of diagonal braces: Within 24 meters of the allowable height required by the specifications, a vertical diagonal brace should be installed every 5 spans per layer along the outer longitudinal direction of the frame, or a steel pipe diagonal brace with fasteners should be installed every 5 spans..
(8) For each horizontal pole layer of double row scaffolding, when there is no hook steel scaffold board to strengthen the stiffness of the horizontal layer: horizontal diagonal poles should be set every 5 spans..
(9) Regarding the requirements for wall connectors: The distance from the connection point between the wall connector and the frame to the buckle node should not exceed 300mm..
1. The degree of quality defects exceeds the requirements of Table 9.3.4 of this specification and cannot be repaired or modified..
6. The verticality deviation between the connecting plate and the outer surface of the steel pipe is greater than 3mm..
7. The wall thickness of the vertical pole is less than 3.05mm, the wall thickness of the horizontal pole is less than 2.35mm, and the wall thickness of the diagonal pole is less than 2.15mm..
8. The service life of hot-dip galvanized surface treated components exceeds 20 years in coastal and humid southern regions, and 25 years in other regions..
The buckle type scaffolding has strong functionality and can be used to set up vertical and horizontal poles into different shapes, structures, and heights of internal and external scaffolding according to different construction requirements and project types in different regions. It can also be used for single and double row scaffolding, bridge frames, and subway tunnel frames. Due to the connection of the upright pole being inserted in the same axis, and the nodes of the horizontal pole being in the same plane, this ensures the stability and load-bearing capacity of the buckle frame. Why does the country constantly require construction units to prohibit bamboo scaffolding, wooden scaffolding, and single row fastener type steel pipe scaffolding?.
I believe everyone should know that the occurrence of construction safety accidents is not only related to factors such as defects in construction technology plans, non-standard installation, illegal operations, and incomplete protective facilities, but also to the poor quality of traditional scaffolding. These traditional scaffolding structures have many drawbacks such as individual differences, poor materials, weak bearing capacity, and broken fasteners. The safety factor is too low, causing significant harm and losses to construction personnel and units..
With the emergence of new types of scaffolding, the country has begun to strongly demand the prohibition of traditional scaffolding and vigorously promote new types of scaffolding. In some large or special engineering projects, the country even forcibly requires the use of new type of buckle scaffolding..
The model of the buckle scaffold is in accordance with the safety technical specification JGJ231-2010 for construction socket type buckle type steel pipe supports,.
Z-type: It is commonly referred to as the 60 series in the market, which means that the diameter of the upright pole is 60.3mm, mainly used for heavy support, such as in bridge engineering..
Type B: also known as the 48 series, with a vertical pole diameter of 48.3mm, mainly used in the fields of building construction and decoration..
In addition, according to the connection method of the buckle type scaffolding pole, it can be divided into two forms: outer shell connection and inner connecting rod connection..
At present, the 60 series buckle scaffolding on the market generally adopts internal connection, which means that the connecting rod is connected inside the upright pole..
The 48 series buckle scaffolding is generally connected by outer sleeves, and there are also internal connecting rods, especially in the fields of stage frames, lighting frames, etc..
Up to now, the new type of buckle scaffolding has been well promoted and applied. It is understood that the current market volume of buckle scaffolding in China has exceeded 38 million tons. In the future, buckle scaffolding will inevitably occupy the mainstream of the scaffolding market. Many construction projects such as buildings, bridges, railways, petroleum and petrochemical industries, and nuclear power projects use buckle scaffolding..
So, what are the benefits of buckle scaffolding? Why are many large-scale projects being used?.
Benefit 1: Improved construction efficiency. One person, one hammer can quickly complete the construction, saving time and labor costs!.
Benefit 2: The construction site has become “tall and upscale”. With the installation of interlocking scaffolding, the construction site has rid itself of “dirty, messy, and poor”!.
Benefit three: The cost of fasteners is reduced, and the frame is more sturdy and stable. Don’t worry about the breakage of the fasteners anymore. The buckle socket type node is welded to the upright pole as a whole, without the need for fasteners, and will not slide or break!.
Benefit 4: The safety of construction personnel is more guaranteed. The high-strength Q345 pole with a buckle can bear a load of up to 200KN, and with the addition of diagonal braces at each node, the load-bearing capacity and stability of the frame are better!.
Benefit 5: More than half of the steel consumption is saved compared to traditional scaffolding!.
Benefit 6: With a lifespan of over 15 years, the cost of single use is definitely lower than that of bamboo scaffolding. The inside and outside of the buckle scaffold are uniformly hot-dip galvanized, waterproof, fireproof, and rust proof, without the need for deliberate maintenance, saving money and trouble!.
