1.0.1 This Code is formulated with a view to implementing the national technical and economic policies in the construction of steel structures and achieving safety and usability, guaranteed quality, advanced technology, and economy and rationality.
1.0.2 This Code is applicable to construction of steel structures in industrial and civil buildings and structures.
1.0.3 The construction of steel structures shall be carried out according to those specified in this Code and quality acceptance shall be carried out for it according to the current national standards of "Unified Standard for Constructional Quality Acceptance of Building Engineering" (GB 50300) and "Code for Acceptance of Construction Quality of Steel Structures" (GB 50205).
1.0.4 The construction of steel structures shall not only meet the requirements of this Code, but also comply with those in the current relevant standards of the nation.
2 Terms and Symbols
2.1 Terms
2.1.1 Design document
A general term for such technical documents as design drawing, design instruction and design change completed by the design organization.
2.1.2 Design drawing
The technical drawing prepared by the design organization as the engineering construction basis.
2.1.3 Detail drawing for construction
The detailed technical drawing drawn according to the technical requirements of the steel structure design drawing and construction processes for direct guidance on fabrication and installation of steel structures.
2.1.4 Temporary structure
The structure that is erected during the construction period and required to be removed at the end of the construction.
2.1.5 Temporary measure
Some necessary structures or temporary parts and member bars, such as lifting hole, connecting plate and auxiliary member that are arranged with a view to meeting the construction demands and guaranteeing engineering safety during the construction period.
2.1.6 Space rigid unit
The basically-stable space system that is composed of members.
2.1.7 Welded hollow spherical node
The node of the pipe that is directly welded to the sphere.
2.1.8 Bolted spherical node
The node that connects the pipe and sphere via -bolts and is composed of parts and components such as the bolted sphere, high strength bolts, sleeve, fastening screw and conical head or closing plate.
2.1.9 Mean slip coefficient
The ratio of the external sliding force to the normal pressure of the connection when high strength bolt’s friction surface sliding.
2.1.10 Structure analysis of construction stage
The structure analysis and calculation carried out in order to meet the requirements of relevant functions during the fabrication, transportation and installation of steel structures.
2.1.11 Preset deformation
The initial deformation set in advance in order to make the structure or member reach the control objectives of the designed geometric positioning after the completion of the construction.
2.1.12 Test assembling
The test assembling carried out in advance to inspect whether the shape and dimension of the member meet the quality requirements.
2.1.13 Ambient temperature
The temperature at the site during the fabrication or installation
2.2 Symbols
2.2.1 Geometric parameters
b - width or free outstanding width of the plate;
d - diameter;
f - deflection and bending rise;
h - section height;
l - length or span;
m - nominal thickness of high strength nut;
n - number of washers;
r - radius;
s - normal thickness of high strength washer;
t - plate and wall thickness;
p - thread pitch;
Δ - gap between contact surfaces or increment;
H - column height;
Ra - surface roughness parameter.
2.2.2 Action and load
P - design pretension force of the high strength bolt;
T - torque of the high strength bolt.
2.2.3 Other
k - coefficient.
3 Basic Requirements
3.0.1 The construction organization of steel structures shall have corresponding construction qualification as well as safety, quality and environmental management system.
3.0.2 Before the construction of the steel structures, technical documents such as construction organization design and its supporting specific construction plan approved by the technical principal of the construction organization shall be provided and submitted to the supervision engineer or the Owner's representative according to the relevant requirements; experts shall be organized to review the technical plan and safety emergency plan for the construction of important steel structures.
3.0.3 In the technical documents and technical contract documents with regard to the construction of steel structures, the construction quality shall at least meet the relevant requirements of the current national standard "Code for Acceptance of Construction Quality of Steel Structures" (GB 50205).
3.0.4 Fabrication and installation of steel structures shall meet the requirements of the design drawing. The construction organization shall carry out process review on the design documents; where it is necessary to change the design, consent from the original design organization shall be obtained and relevant design change documents shall be transacted.
3.0.5 During the construction and quality acceptance of steel structures, effective measuring instruments & tools shall be used. The construction organizations and supervision organizations in various professions shall unify the measurement standard.
3.0.6 Special equipment and tool for construction of steel structures shall meet the construction requirements and shall be within the validity of the qualified verification.
3.0.7 For the construction of steel structures, quality process control shall be carried out according to the following requirements:
1 Site acceptance is carried out for the materials and finished products; re-inspection is carried out for the materials and semi-finished products related to the safety and function according to the relevant requirements; witness sampling and sample delivery are adopted;
2 Quality control is carried out for each process according to the requirements of the construction processes and process inspection is carried out;
3 Handing-over inspection is carried out between relevant professions and work types;
4 Quality acceptance is carried out before the closure of the concealed work.
3.0.8 The new technology, process, material and structure not involved in this Code shall be tested before use for the first time, for which necessary supplementary standards shall be determined according to the test results and subject to the expert demonstration.
1 General Provisions 2 Terms and Symbols 2.1 Terms 2.2 Symbols 3 Basic Requirements 4 Design of Construction Stage 4.1 General Requirements 4.2 Structure Analysis of Construction Stage 4.3 Preset Deformation of Structure 4.4 Detail Design 5 Materials 5.1 General Requirements 5.2 Steel Materials 5.3 Welding Materials 5.4 Fasteners 5.5 Steel Castings, Anchorages and Pins 5.6 Coating Materials 5.7 Material Storage 6 Welding 6.1 General Requirements 6.2 Welding Personnel 6.3 Welding Procedure 6.4 Welded Joints 6.5 Welding Quality Inspection 6.6 Repair of Welding Defects 7 Connection of Fasteners 7.1 General Requirements 7.2 Preparation of Connecting Pieces and Friction Surface Treatment 7.3 Connection of Ordinary Fasteners 7.4 Connection of High Strength Bolts 8 Processing of Parts and Components 8.1 General Requirements 8.2 Setting out and Marking-off 8.3 Cutting 8.4 Rectification and Formation 8.5 Trimming of Edges 8.6 Holing 8.7 Processing of Bolted Spheres and Welded Hollow Spheres 8.8 Processing of Cast Steel Node 8.9 Processing of Rope Nodes 9 Assembling and Processing of Members 9.1 General Requirements 9.2 Assembling of Components 9.3 Assembling of Members 9.4 Milling of Member Ends 9.5 Rectification of Members 10 Test Assembling of Steel Structures 10.1 General Requirements 10.2 Test Assembling of Steel Structures 10.3 Test Assembling of Computer Assistance Simulation 11 Installation of Steel Structures 11.1 General Requirements 11.2 Hoisting Equipment and Hoisting Mechanism 11.3 Foundation, Bearing Surface and Embedment Parts 11.4 Installation of Members 11.5 Single-story Steel Structures 11.6 Multi-story and Tall Steel Structures 11.7 Long-span Spatial Steel Structures 11.8 High-rising Steel Structures 12 Profiled Metal Plate 13 Coating 13.1 General Requirements 13.2 Surface Treatment 13.3 Coating of Anticorrosive Paint Layer 13.4 Metal Hot Spraying 13.5 Anticorrosion of Hot Dipping Galvanizing 13.6 Coating of Fire-retardant Coating Layer 14 Construction Survey 14.1 General Requirements 14.2 Plan Control Network Survey 14.3 Elevation Control Network Survey 14.4 Survey of Single-story Steel Structures 14.5 Survey of Multi-story and Tall Steel Structures 14.6 Survey of High-rising Steel Structures 15 Construction Monitoring 15.1 General Requirements 15.2 Construction Monitoring 16 Construction Safety and Environmental Protection 16.1 General Requirements 16.2 Climb Up 16.3 Safety Channel 16.4 Protection of Portals and Sides 16.5 Construction Machinery and Equipment 16.6 Safety of Site Hoisting Area 16.7 Fire Safety Measures 16.8 Environmental Protection Measures Explanation of Wording in This Code List of Quoted Standards
1 General Provisions
1.0.1 This Code is formulated with a view to implementing the national technical and economic policies in the construction of steel structures and achieving safety and usability, guaranteed quality, advanced technology, and economy and rationality.
1.0.2 This Code is applicable to construction of steel structures in industrial and civil buildings and structures.
1.0.3 The construction of steel structures shall be carried out according to those specified in this Code and quality acceptance shall be carried out for it according to the current national standards of "Unified Standard for Constructional Quality Acceptance of Building Engineering" (GB 50300) and "Code for Acceptance of Construction Quality of Steel Structures" (GB 50205).
1.0.4 The construction of steel structures shall not only meet the requirements of this Code, but also comply with those in the current relevant standards of the nation.
2 Terms and Symbols
2.1 Terms
2.1.1 Design document
A general term for such technical documents as design drawing, design instruction and design change completed by the design organization.
2.1.2 Design drawing
The technical drawing prepared by the design organization as the engineering construction basis.
2.1.3 Detail drawing for construction
The detailed technical drawing drawn according to the technical requirements of the steel structure design drawing and construction processes for direct guidance on fabrication and installation of steel structures.
2.1.4 Temporary structure
The structure that is erected during the construction period and required to be removed at the end of the construction.
2.1.5 Temporary measure
Some necessary structures or temporary parts and member bars, such as lifting hole, connecting plate and auxiliary member that are arranged with a view to meeting the construction demands and guaranteeing engineering safety during the construction period.
2.1.6 Space rigid unit
The basically-stable space system that is composed of members.
2.1.7 Welded hollow spherical node
The node of the pipe that is directly welded to the sphere.
2.1.8 Bolted spherical node
The node that connects the pipe and sphere via -bolts and is composed of parts and components such as the bolted sphere, high strength bolts, sleeve, fastening screw and conical head or closing plate.
2.1.9 Mean slip coefficient
The ratio of the external sliding force to the normal pressure of the connection when high strength bolt’s friction surface sliding.
2.1.10 Structure analysis of construction stage
The structure analysis and calculation carried out in order to meet the requirements of relevant functions during the fabrication, transportation and installation of steel structures.
2.1.11 Preset deformation
The initial deformation set in advance in order to make the structure or member reach the control objectives of the designed geometric positioning after the completion of the construction.
2.1.12 Test assembling
The test assembling carried out in advance to inspect whether the shape and dimension of the member meet the quality requirements.
2.1.13 Ambient temperature
The temperature at the site during the fabrication or installation
2.2 Symbols
2.2.1 Geometric parameters
b - width or free outstanding width of the plate;
d - diameter;
f - deflection and bending rise;
h - section height;
l - length or span;
m - nominal thickness of high strength nut;
n - number of washers;
r - radius;
s - normal thickness of high strength washer;
t - plate and wall thickness;
p - thread pitch;
Δ - gap between contact surfaces or increment;
H - column height;
Ra - surface roughness parameter.
2.2.2 Action and load
P - design pretension force of the high strength bolt;
T - torque of the high strength bolt.
2.2.3 Other
k - coefficient.
3 Basic Requirements
3.0.1 The construction organization of steel structures shall have corresponding construction qualification as well as safety, quality and environmental management system.
3.0.2 Before the construction of the steel structures, technical documents such as construction organization design and its supporting specific construction plan approved by the technical principal of the construction organization shall be provided and submitted to the supervision engineer or the Owner's representative according to the relevant requirements; experts shall be organized to review the technical plan and safety emergency plan for the construction of important steel structures.
3.0.3 In the technical documents and technical contract documents with regard to the construction of steel structures, the construction quality shall at least meet the relevant requirements of the current national standard "Code for Acceptance of Construction Quality of Steel Structures" (GB 50205).
3.0.4 Fabrication and installation of steel structures shall meet the requirements of the design drawing. The construction organization shall carry out process review on the design documents; where it is necessary to change the design, consent from the original design organization shall be obtained and relevant design change documents shall be transacted.
3.0.5 During the construction and quality acceptance of steel structures, effective measuring instruments & tools shall be used. The construction organizations and supervision organizations in various professions shall unify the measurement standard.
3.0.6 Special equipment and tool for construction of steel structures shall meet the construction requirements and shall be within the validity of the qualified verification.
3.0.7 For the construction of steel structures, quality process control shall be carried out according to the following requirements:
1 Site acceptance is carried out for the materials and finished products; re-inspection is carried out for the materials and semi-finished products related to the safety and function according to the relevant requirements; witness sampling and sample delivery are adopted;
2 Quality control is carried out for each process according to the requirements of the construction processes and process inspection is carried out;
3 Handing-over inspection is carried out between relevant professions and work types;
4 Quality acceptance is carried out before the closure of the concealed work.
3.0.8 The new technology, process, material and structure not involved in this Code shall be tested before use for the first time, for which necessary supplementary standards shall be determined according to the test results and subject to the expert demonstration.
Contents of GB 50755-2012
1 General Provisions
2 Terms and Symbols
2.1 Terms
2.2 Symbols
3 Basic Requirements
4 Design of Construction Stage
4.1 General Requirements
4.2 Structure Analysis of Construction Stage
4.3 Preset Deformation of Structure
4.4 Detail Design
5 Materials
5.1 General Requirements
5.2 Steel Materials
5.3 Welding Materials
5.4 Fasteners
5.5 Steel Castings, Anchorages and Pins
5.6 Coating Materials
5.7 Material Storage
6 Welding
6.1 General Requirements
6.2 Welding Personnel
6.3 Welding Procedure
6.4 Welded Joints
6.5 Welding Quality Inspection
6.6 Repair of Welding Defects
7 Connection of Fasteners
7.1 General Requirements
7.2 Preparation of Connecting Pieces and Friction Surface Treatment
7.3 Connection of Ordinary Fasteners
7.4 Connection of High Strength Bolts
8 Processing of Parts and Components
8.1 General Requirements
8.2 Setting out and Marking-off
8.3 Cutting
8.4 Rectification and Formation
8.5 Trimming of Edges
8.6 Holing
8.7 Processing of Bolted Spheres and Welded Hollow Spheres
8.8 Processing of Cast Steel Node
8.9 Processing of Rope Nodes
9 Assembling and Processing of Members
9.1 General Requirements
9.2 Assembling of Components
9.3 Assembling of Members
9.4 Milling of Member Ends
9.5 Rectification of Members
10 Test Assembling of Steel Structures
10.1 General Requirements
10.2 Test Assembling of Steel Structures
10.3 Test Assembling of Computer Assistance Simulation
11 Installation of Steel Structures
11.1 General Requirements
11.2 Hoisting Equipment and Hoisting Mechanism
11.3 Foundation, Bearing Surface and Embedment Parts
11.4 Installation of Members
11.5 Single-story Steel Structures
11.6 Multi-story and Tall Steel Structures
11.7 Long-span Spatial Steel Structures
11.8 High-rising Steel Structures
12 Profiled Metal Plate
13 Coating
13.1 General Requirements
13.2 Surface Treatment
13.3 Coating of Anticorrosive Paint Layer
13.4 Metal Hot Spraying
13.5 Anticorrosion of Hot Dipping Galvanizing
13.6 Coating of Fire-retardant Coating Layer
14 Construction Survey
14.1 General Requirements
14.2 Plan Control Network Survey
14.3 Elevation Control Network Survey
14.4 Survey of Single-story Steel Structures
14.5 Survey of Multi-story and Tall Steel Structures
14.6 Survey of High-rising Steel Structures
15 Construction Monitoring
15.1 General Requirements
15.2 Construction Monitoring
16 Construction Safety and Environmental Protection
16.1 General Requirements
16.2 Climb Up
16.3 Safety Channel
16.4 Protection of Portals and Sides
16.5 Construction Machinery and Equipment
16.6 Safety of Site Hoisting Area
16.7 Fire Safety Measures
16.8 Environmental Protection Measures
Explanation of Wording in This Code
List of Quoted Standards
