GB 50205-2020 Standard for acceptance of construction quality of steel structures English
1 General provisions
1.0.1 This standard is developed with a view to strengthening the quality management of construction projects, standardizing the acceptance of construction quality of steel structures, and ensuring the quality of steel structures.
1.0.2 This standard is applicable to the acceptance of construction quality of steel structures for industrial and civil buildings and structures.
1.0.3 This standard shall be used together with the current national standard GB 50300 Unified standard for constructional quality acceptance of building engineering.
1.0.4 In addition to this standard, acceptance of construction quality of steel structures shall also comply with those stipulated in the current relevant standards of the nation.
2 Terms and symbols
2.1 Terms
2.1.1
part
smallest unit of a component or element, e.g. gusset plate, flange plate, etc.
2.1.2
component
unit consisting of several parts, e.g. welded H-beam and steel bracket
2.1.3
element
basic unit of steel structure composed of parts or parts and components, e.g. beam, column, support, etc.
2.1.4
the smallest assembled rigid unit
smallest installation unit except for loose items in the installation engineering of steel grid and reticulated shell structures, generally divided into two types, i.e. plane truss and cone
2.1.5
assembly of high strength bolt
generic term of high-strength bolt, nut and washer
2.1.6
anti-slip coefficient
ratio of the external force making the friction surface of the connector slide to the sum of the pretension of the high-strength bolt perpendicular to the friction surface in high-strength bolt connection
2.1.7
test assembling
assembling to test whether the elements meet the installation quality requirements
2.1.8
space rigid unit
spatially stable structure composed of elements
2.1.9
stud welding
welding process of subjecting one end of stud (welding nail) and the surface of plate (or piping) components to electrifying and arc striking until the faying surface melted, and applying a certain pressure on the stud (welding nail)
2.1.10
ambient temperature
site temperature during fabrication or installation
2.1.11
membrane structure
building (structure) consisting of membrane and its supporting element
2.1.12
PVC membrane
cloth-like material formed by coating polyvinyl chloride resin on woven fabric
2.1.13
PTFE membrane
cloth-like material formed by coating polytetrafluoroethylene resin on woven fabric
2.1.14
ETFE membrane
single cloth-like polyester material directly made of ethylene-tetra-fluoro-ethylene material
2.1.15
overlapping adjacent metal sheet
profiled metal sheet with longitudinal profiled edge that can be overlapped, attached to the structure with fasteners after being overlapped
2.1.16
up standing seam metal sheet
profiled metal sheet with longitudinal profiled edge that can be overlapped, curled and seamed with special machine along its length, and attached to the structure with fixed bracket after being overlapped
2.1.17
clip-lock metal sheet
profiled metal sheet with longitudinal profiled edge that can be overlapped, attached to the structure by locking and with fixed bracket
2.1.18
flashing
element of a certain shape formed of metal sheet by rolling or mechanical bending, which is used to seal the gap of the profiled metal sheet on the roof and wall against seepage of rainwater
2.1.19
metal roofing system
generic term of roof enclosure system composed of metal cover fixed bracket, bottom plate, fasteners, thermal insulation materials, barrier materials, acoustic materials, etc.
2.2 Symbols
2.2.1 Action and effect of action:
P——the design value of pretension of a high-strength bolt;
ΔP——the loss value of pretension of a high-strength bolt;
Tch——the checked torque of a high-strength bolt;
Tc——the final torque of a high-strength bolt;
T0——the initial torque of a high-strength bolt.
2.2.2 Geometric parameters:
a——the spacing;
b——the width or free outstanding width of a plate;
d——the diameter;
d0——the hole diameter;
e——the eccentricity;
f——the deflection or the bending rise;
H——the height;
Hi——the height of each structural floor;
h——the section height;
he——the calculated thickness of fillet weld;
l——the length or the span;
r——the radius;
t——the thickness of plate or wall;
Δ——the variable.
2.2.3 Others:
K——the wind resistance coefficient;
μ——the anti-slip coefficient;
Ra——the arithmetical mean deviation of the profile (surface roughness parameter).
3 Basic requirements
3.0.1 Any construction organization of steel structures shall have corresponding construction technology standards, quality management system, and quality control and inspection system. Approved construction organization design, construction scheme and other technical documents shall be available at the construction site.
3.0.2 The acceptance of construction quality of steel structures must be carried out with the measuring instruments that have passed the metrological verification and calibration. Witness sampling and delivery of steel structure work shall be completed by the testing organization.
3.0.3 The engineering and technology documents, contract documents, etc. used in the steel structures construction shall not be inferior to this standard with regard to construction quality acceptance requirements.
3.0.4 Steel structure work shall be subjected to construction quality control according to the following requirements:
1 The raw materials and finished products used shall be subjected to site acceptance; those related to safety and function shall be reinspected according to the requirements of subclause 14.0.2 of this standard and then subjected to witness sampling and delivery by the Supervision Engineer (Technical Director of development organization).
2 Each process shall be subjected to the quality control according to the technical standard for construction, and the construction inspection shall be carried out at the end of each process;
3 Handing over inspection shall be carried out between relevant specialties and shall be checked and approved by the Supervision Engineer (Technical Director of development organization).
3.0.5 Acceptance of construction quality of steel structures shall be carried out by inspection lot, subitem work, subsection (sub-subsection) work, after the steel structures pass the self-inspection made by the construction organization. Among subsection (sub-subsection) work, subitem work shall be divided according to the requirements of the current national standard GB 50300 Unified standard for constructional quality acceptance of building engineering. Subitem work of steel structures shall consist of one or several inspection lots; the inspection lot of each subitem work shall be divided according to the requirements of this standard, and confirmed by the Supervisor (or development organization).
1 General provisions
2 Terms and symbols
2.1 Terms
2.2 Symbols
3 Basic requirements
4 Acceptance of raw materials and finished products
4.1 General requirements
4.2 Steel plate
4.3 Profiles and pipes
4.4 Steel castings
4.5 Stay cables, tie rods and anchors
4.6 Welding consumables
4.7 Standard fasteners for connection
4.8 Material of spherical joint
4.9 Profiled metal sheet
4.10 Membrane materials of membrane structures
4.11 Coating materials
4.12 Finished products and others
5 Welding engineering
5.1 General requirements
5.2 Welding engineering of steel elements
5.3 Stud (welding nail) welding engineering
6 Connection engineering of fasteners
6.1 General requirements
6.2 Connection of ordinary fasteners
6.3 Connection of high strength bolts
7 Processing of steel parts and steel components
7.1 General requirements
7.2 Cutting
7.3 Rectification and formation
7.4 Trimming of edges
7.5 Processing of spherical joints
7.6 Processing of steel castings
7.7 Holing
8 Assembling engineering of steel elements
8.1 General requirements
8.2 Assembling and butting of components
8.3 Assembling
8.4 Milling of element ends and compacting of faying surface
8.5 Shapes and sizes of steel elements
9 Test assembling engineering of steel elements
9.1 General requirements
9.2 Entity test assembling
9.3 Simulation test assembling
10 Installation engineering of single-storey/multi-storey steel frame structures
10.1 General requirements
10.2 Foundation and anchor bolt (anchor)
10.3 Installation of steel columns
10.4 Installation of steel roof truss (shelves) and beams (truss)
10.5 Installation of connection joints
10.6 Installation of steel plate shear wall
10.7 Installation of supports, purlins, wall frames and secondary structures
10.8 Installation of steel platforms and stairs
10.9 Overall steel structures
11 Installation engineering of space structures
11.1 General requirements
11.2 Installation of bearing and anchor bolt (anchor)
11.3 Installation of steel grid structure and reticulated shell
11.4 Steel pipe truss structure
11.5 Making of cable and member
11.6 Making of membrane elements
11.7 Installation of cable and member
11.8 Installation of membrane structure
12 Profiled metal sheet engineering
12.1 General requirements
12.2 Making of profiled metal sheet
12.3 Installation of profiled metal sheet
12.4 Installation of fixed bracket
12.5 Connection construction and joints
12.6 Metal roofing system
13 Coating engineering
13.1 General requirements
13.2 Anticorrosive coating painting
13.3 Coating of connection parts and repairing of coating defects
13.4 Fire resistive coating
14 Subsection completion acceptance of steel structures
Annex A Inspection items and methods of steel products
Annex B Inspection items of fastener connection engineering
Annex C Wind resistance performance testing methods of metal roofing system
Annex D Process assessment of anticorrosive coating
Annex E Determination methods of thick-layered fire resistant paint coating thickness
Annex F Inspection and witness inspection items related to safety and function of steel structure works
Annex G Visual quality inspection items related to steel structure works
Annex H Quality acceptance record of inspection lot of steel structure subitem works
Annex J Measurement method of steel structure works
Explanation of wording in this standard
List of quoted standards
