GB 51210-2016Unified standard for safety of scaffold in construction (English PDF)

1.0.2 This standard applies to the design, construction, use, management of scaffolding

for housing construction projects and municipal engineering construction.

1.0.3 In addition to complying with this standard, the design, construction, use, management of construction scaffolding shall also comply with the relevant national standards.

2.1 Terms

2.1.1 Scaffold

It is a structural frame composed of rods or structural units and accessories that are reliably connected, can withstand corresponding loads, has safety protection functions, provides operating conditions for building construction. It includes operation scaffold and shoring scaffold.

2.1.2 Operation scaffold

Scaffolding which is composed of rods or structural units and accessories through reliable connections, supported on the ground, buildings or attached to engineering structures, to provide a working platform and safety protection for construction. It includes floor-standing operation scaffold, cantilever scaffold, attached lifting scaffold, etc. as formed by various types of rods (components), which are referred to as operation scaffold.

3.1 General requirements

3.1.1 Before scaffolding installation and dismantlement, a special construction plan

shall be prepared according to the characteristics of the project; its implementation shall be organized after approval.

3.1.2 The structural design of the scaffolding shall be able to ensure the stability of the scaffolding structural system.

3.1.4 Scaffolding shall be reasonably constructed, firmly connected, easy to erect and dismantle, safe and reliable to use.

3.2 Safety levels and safety factors

5.1 Load classification and normal value

5.1.1 The load acting on the scaffold shall be divided into permanent load and variable load.

5.1.4 The standard value of the permanent load of the scaffold shall comply with the following requirements.

5.1.6 Vibrating and impacting objects on the scaffold shall be calculated into the standard value of variable load, based on their own weight multiplied by the dynamic factor. The possible value of the dynamic factor is 1.35.

5.1.7 The standard value of horizontal wind load acting on the scaffold shall be calculated according to the following formula.

5.2 Load combination

5.2.1 Scaffolding design shall be based on the loads that may occur simultaneously on the scaffold, during normal installation and use. Load combinations shall be carried out according to the load-bearing capacity limit state and the serviceability limit state; the most unfavorable load combination shall be used for design.

5.2.3 When designing the normal serviceability limit state of the scaffolding structure

and accessories, the standard combination of loads shall be adopted in accordance with the following provisions.

6.1 General requirements

6.1.1 Scaffolding design shall adopt the limit state design method based on probability

theory and calculate with partial factor design expressions.

6.1.2 The load-bearing structure of the scaffold shall be designed according to the load-bearing capacity limit state and the serviceability limit state; it shall also comply with the following requirements.

6.1.3 Scaffolding shall be designed according to normal installation and normal use

conditions; temporary effects, accidental effects, seismic loads may not be taken into account.

6.1.7 The design value of the bearing capacity of the scaffolding rod's connection nodes shall comply with the following requirements.

6.1.8 The technical parameters, such as the design value of steel strength of steel pipe scaffold, shall comply with the following requirements.

6.1.9 The technical parameters, such as the design value of wood strength of wooden scaffold, shall comply with the provisions of the current national standard "Code for design of timber structures" GB 50005.

6.2.2 The bearing capacity of scaffolding rod's connection nodes shall meet the following requirements.

6.2.4 Calculation of stable bearing capacity of operation scaffold standards (gate

scaffolding standards) shall comply with the following requirements.

6.3 Serviceability limit state

6.3.1 When the scaffolding structure or accessories are designed according to the serviceability limit state, they shall meet the following requirements.

6.3.2 When designing according to the serviceability limit state, the calculation of the standard value of the permanent load shall comply with the following provisions.

7.1 General requirements

7.1.1 The structural analysis of scaffolding shall include the load effect analysis and resistance analysis of the scaffolding structure, scaffolding structure accessories, rod connection nodes, which can be carried out by simulation calculation, model testing and structural testing.

7.1.3 The physical and mechanical properties of scaffold accessories shall be determined or verified through tests. During type inspection of scaffold accessories, the following tests shall be carried out.

7.1.5 The test of scaffold structure and scaffold structure accessories shall adopt random sampling method to select test pieces; the sample for testing shall be representative of the technical quality characteristics of the materials and accessories under inspection.

7.2 Frame test and analysis

7.2.1 The basic assumptions and calculation models used in the structural analysis of the scaffold shall be determined based on the structure, construction, stress characteristics of the scaffold in its working state. When the structure and construction of the scaffold change, the calculation parameters of the scaffold shall be re-determined.

7.2.3 The scaffolding structure test shall be carried out using the unit structure test method; the unit structure test results shall be compared and analyzed with the model test results to comprehensively determine the bearing capacity value of the scaffolding structure, which shall comply with the following requirements.

7.3.4 When analyzing the bearing capacity of scaffolding rod's connection nodes, the impact of possible elastic deformation of the scaffold on the node bearing capacity shall be taken into account; corrections shall be made through tests or theoretical analysis when necessary.

8.1 General requirements

8.1.1 The structure and assembly process of the scaffold shall be able to meet the construction needs; the structure shall be ensured to be firm and stable.

8.1.5 Bamboo scaffold shall only be used for operation scaffold and floor-to-ceiling

shoring scaffold, whilst wooden scaffold can be used for operation scaffold and shoring scaffold. The structure and node connection technical requirements of bamboo and wooden scaffold shall comply with the provisions of the current national standards related to scaffold.

8.2 Operation scaffold

8.2.1 The width of the operation scaffold shall not be less than 0.8 m and should not be greater than 1.2 m. The height of the working floor shall not be less than 1.7 m and should not be greater than 2.0 m.

8.2.3 Vertical scissor braces shall be installed on the longitudinal outer facade of the operation scaffold, which shall meet the following requirements.

8.2.5 Vertical and horizontal bottom reinforcing tubes shall be installed on the bottom

standards of the operation scaffold.

8.2.6 The bottom of the cantilever scaffolding standard shall be reliably connected to the cantilever support structure; a longitudinal bottom reinforcing tube shall be set at the bottom of the standard; horizontal scissor braces or horizontal diagonal braces shall be set intermittently.

8.3 Shoring scaffold

8.3.1 The spacing and lift height between standards of shoring scaffold shall be determined according to design calculations; the spacing should not be greater than 1.5 m; the lift height shall not be greater than 2.0 m.

8.3.2 The aspect ratio of the independent scaffold for the shoring scaffold shall not be greater than 3.0.

8.3.13 The length of the adjustable base plate and adjustable base jack of the shoring scaffold, as inserted into the standards, shall not be less than 150 mm; the extension length of the adjustable screw shall not be greater than 300 mm. When the extension length of the adjustment screw of adjustable base jack is relatively large, it should provide limiting measures in the horizontal direction; the extension length of the adjustable screw shall be determined according to calculations.

9.0.1 Scaffold installation and dismantlement operations shall be carried out according

to the special construction plan.

9.0.2 Before scaffold installation operations, safety technical briefings shall be given to the workers.

9.0.5 The installation of tie members of operation scaffold must comply with the following requirements.

9.0.7 After the attached lifting scaffold is assembled in place, it shall be inspected, lifted, and debugged according to requirements. It can be put into use only after meeting the requirements.

9.0.8 The dismantling of scaffold must comply with the following requirements.

9.0.10 Heavy hammering or prying is not allowed during the dismantling of scaffolding.

The dismantled rods and accessories shall be transported to the ground mechanically or manually; throwing is strictly prohibited.

9.0.11 When shoring scaffold is continuously erected on multi-story floors, the impact

of load transfer between multi-story floors on the shoring scaffold and building structure shall be analyzed. The standards of the shoring scaffold on the upper and lower floors should be set in opposite direction.