According to the requirements of Notice on Printing (JIANBIAO [2002] No.84) issued by the original Ministry of Construction (MOC), the code drafting group revised this code via extensive investigation, careful summarization of practical experience, reference to relevant international and foreign advanced standards, and widely soliciting for opinions.
Main technical contents of this code are: 1. General Provisions; 2. Terms and Symbols; 3. Basic Requirements; 4. Edge-near and Opening Operation; 5. Climbing and Hanging Operation; 6. Operating Platform; 7. Cross Operation; 8. Safety Nets in Building Construction.
Main technical contents revised in this code: 1. The Clause "Terms and Symbols" is added; 2. Requirements for protective railings in edge-near and opening operation are concluded and collated to specify the structure of them uniformly; 3. In the Clause "Climbing and Hanging Operation", safety protection requirements for roof and exterior wall operation are added; 4. The Clause "Operating Platform and Cross Operation" is divided to two Clauses, "Operating Platform" and "Cross Operation", and the requirements for them are proposed respectively; 5. Requirements are respectively proposed for movable operating platform, floor type operating platform and cantilevered operating platform; 6. The Clause "Safety Nets in Building Construction" is added and specific requirements are proposed for the arrangement of safety nets.
In this code, the requirements printed in bold type are compulsory and must be enforced strictly.
The Ministry of Housing and Urban-Rural Development is in charge of the administration of this code and the explanation of the compulsory provisions while Shanghai Construction Design and Research Institute Co., Ltd. is responsible for the explanation of specific technical contents. During the process of implementing this code, the relevant opinions and advice, whenever necessary, can be sent to Shanghai Construction Design and Research Institute Co., Ltd. (Address: No.1 building, No.51 Wuzhong Road, Shanghai, China; postcode: 200235,).
1 General Provisions
1.0.1 This code is formulated with view to standardizing the working at height of building construction and its management as well as realizing safe protection, advanced technology and economic rationality.
1.0.2 This code is applicable to operation like edge-near, opening, climbing, hanging, operating platform, cross operation and safety net erection in working at height of building engineering construction.
This code is also applicable to working at height for constructing other parts such as caves, pits, ditches and grooves.
1.0.3 During working at height of building construction, not only the requirements stipulated in this code but also those stipulated in the current relevant standards of the nation shall be complied with.
2 Terms and Symbols
2.1 Terms
2.1.1 working at height
operation carried out at falling height datum plane of 2m and above with the possibility of falling
2.1.2 edge-near operation
working at height on working face with or without enclosure facilities at edge and less than 800mm in height, including working at height on slab edge, flight of steps edge, roof edge, balcony edge and edges of all kinds of pits, ditches and grooves
2.1.3 opening operation
working at height on ground, floor, roof and wall surface where people or materials may fall from opening with height of 2m or above
2.1.4 climbing operation
working at height carried out by virtue of climbing instruments or facilities
2.1.5 hanging operation
working at height carried out in suspending state where there is no protection facility around or protection facilities fail to meet the protection requirements
2.1.6 operating platform
platform at construction site which is erected by steel tube, profile steel and other materials of equivalent performance and used for working at height and carrying materials, including movable, floor type and cantilevered operating platforms
2.1.7 movable operating platform
movable scaffold operating platform with caster or guide track
2.1.8 floor type operating platform
immovable operating platform erected from ground or floor, which may be a construction platform simply for construction operation or material receiving platform for construction operation and bearing materials
2.1.9 cantilevered operating platform
operating platform placed or fixed on building structure edge with the form of cantilever, including cable-stayed and supported cantilevered operating platforms
2.1.10 cross operation
three-dimensional operation within the range of falling radius carried out at different levels (upper, lower, left and right) under the state of vertical space penetration, which may lead to personnel or object falling
2.1.11 safety protecting facilities
equipment arranged and measures adopted for controlling hazardous and harmful factors in safety range as well as reducing, preventing and eliminating hazards in working at height of construction
2.1.12 safety protecting shed
protecting sheds erected to prevent personnel or materials and equipment within falling radius from being injured or damaged by falling object in fly-over cross operation of working at height
2.2 Symbols
2.2.1 Action and effect of action
Fbk——the standard value of concentrated load born by upper cross bar;
Fck——the standard value of concentrated load on secondary beam;
Fzk——the standard value of concentrated load born by vertical bar;
M——the design value of the maximum bending moment of upper cross bar;
Mc——the design value of the maximum bending moment of secondary beam;
My——the design value of the maximum bending moment of main beam;
Mz——the design value of the maximum bending moment born by vertical bar;
N——the design value of axial pressure of brace;
Nz——the design value of axial pressure of vertical bar;
q——the design value of equivalent uniform load on beam;
——the standard value of equivalent and variable load uniformly distributed on secondary beam;
——the standard value of dead load uniformly distributed on secondary beam;
R——the counter force of support generated by placing secondary beam on outer side of main beam.
Ss——the breaking force of steel wire rope;
T——the standard value of tension born by steel wire rope;
σ1——the bending stress of member bar;
σ2——the compression stress of vertical bar.
2.2.2 Calculation indexes
E——the elastic modulus of member bar;
f1——the design value of bending strength of member bar;
f2——the design value of compressive strength of vertical bar;
f3——the design value of compressive strength of brace.
2.2.3 Calculated coefficients
[K]——the permissible safety coefficient of steel wire rope used as catenary wire;
——the stability coefficient of axial compressive member.
2.2.4 Geometrical factors
A——the gross section area of vertical bar;
An——the net section area of vertical bar;
Ac——the gross section area of brace;
a——the length of cantilever;
h——the height of vertical bar;
I——the inertia moment of member bar section;
L0——the calculated length of upper cross bar;
L0C——the calculated span of secondary beam;
Lx——the span between supporting points on both ends of secondary beam;
L0y——the calculated span of main beam;
Wn——the resisting moment of net section of upper bar;
Wzn——the resisting moment of net section of vertical bar;
α——the included angle between steel wire rope and platform surface;
η——the length ratio of cantilever;
v——the calculated deflection value of bending member;
[v]——the permissible deflection value of bending member.
3 Basic Requirements
3.0.1 For building construction involving edge-near and opening operation, climbing and hanging operation, operating platform, cross operation and erection of safety net, technical safety measures for working at height shall be formulated in construction organization design or construction scheme.
3.0.2 Before construction of working at height, inspection and acceptance shall be carried out for safety protecting facilities according to types and the operation may be carried out after passing the acceptance. The acceptance shall be recorded and may be carried out by levels or by phases.
3.0.3 Before construction of working at height, safety technical disclosure shall be carried out for operation personnel and shall be recorded. Training shall be carried out for personnel operating for the first time.
3.0.4 Various safety warning signs shall be hung at corresponding positions in construction site as required and red warning light shall be arranged at night. Before the construction of working at height, safety signs, tools, instruments, electrical facilities and equipment for working at height shall be inspected and construction may be conducted after they are confirmed as intact.
3.0.5 Personnel working at height shall be equipped with corresponding safety protection articles according to the actual operation situation of as well as wear and use corresponding safety protection articles and instruments as required.
3.0.6 Materials at construction operation site with the possibility of falling shall be dismantled or fixed in time. Materials for working at height shall be stacked stably and shall not obstruct traffic, loading and unloading. Tools shall be placed in tool bag when they are not be used; walkway, channel plate and climbing instruments in operation shall be cleaned up when they are not be used; materials from dismantlement, residual materials and waste materials shall be cleared and carried away timely and shall not be placed or discarded downward without permission. It is forbidden to transmit materials by throwing.
3.0.7 Fire control measures shall be adopted for working at height according to those specified in the current national standard GB 50720 Technical code for fire safety of construction site.
3.0.8 When working at height and at weather like rain, frost, fog and snow, anti-skidding, anti-freezing and anti-lightning measures shall be taken, and the water, ice, snow or frost on working face shall be cleaned up timely.
If atrocious weather like strong wind of Grade 6 and above, thick fog and sandstorm is encountered, the climbing and hanging operation at height in open air shall not be carried out. After rain & snow, safety facilities for working at height shall be inspected; if any phenomenon such as looseness, deformation, damage or shedding is found, repair shall be carried out timely and these facilities may not be used until they are qualified after repair.
3.0.9 Safety protecting facilities required to be dismantled or moved temporarily shall be provided with reliable measures and restored immediately after operation.
3.0.10 The acceptance for safety protecting facilities shall include the following main contents:
1 Arrangement and erection of protective railings;
2 Erection of instruments and facilities for climbing and hanging operation;
3 Erection of operating platform and platform protection facilities;
4 Erection of protecting shed;
5 Arrangement of safety net;
6 Performance and quality of safety protecting facilities and equipment, specification of materials and accessories used;
7 Joint construction of facilities, specification of materials and accessories and the fixation and connection states with building.
3.0.11 Acceptance data of safety protecting facilities shall include the following main contents:
1 Technical safety measures or construction scheme in construction organization design;
2 Product qualification certificates of safety protection articles, instruments, materials and equipment;
3 Acceptance records of safety protecting facilities;
4 Acceptance records of concealed embedment parts;
5 Change records of safety protecting facilities.
3.0.12 Inspection, repair and maintenance for all kinds of safety protecting facilities shall be carried out by specific personnel and rectification measures shall be adopted timely after finding potential hazards.
3.0.13 Finalized and mechanized facilities should be adopted as safety protecting facilities; protective railings shall be marked with black and yellow or red and white streak; covering parts shall have yellow or red mark.
4 Edge-near and Opening Operation
4.1 Edge-near Operation
4.1.1 When the edge-near operation is carried out at the datum plane with falling height of 2m or above, protective railings shall be set at the suspending side and the fine mesh safety vertical net or tool-typed breast board shall be adopted to close the datum plane.
4.1.2 Protective railings shall be installed at the stairway, stair landing and stair flight edge; fine mesh safety vertical net shall be installed at outer stairway, stair landing and stair flight edge as enclosure.
4.1.3 For the outer side and edge of building, protective railings shall be set for engineering without external scaffold; fine mesh safety vertical net shall be adopted for engineering with external scaffold as enclosure. The fine mesh safety vertical net shall be set on the vertical bar at the outer side of scaffold and shall be connected firmly with scaffold bar.
4.1.4 For stop layer platforms of construction hoist, gantry frame and headframe hoist arranged between buildings, protective railings and toe board shall be set on both sides of them, and fine mesh safety vertical net or tool-typed breast board shall be adopted as enclosure.
4.1.5 Storey protective door with height not less than 1.80m and devices to prevent outward opening shall be set at the platform interface of stop layer. Isolation facilities shall be set respectively in the middle of channel of headframe hoist.
4.2 Opening Operation
4.2.1 Anti-falling measures shall be taken during opening operation and shall meet the following requirements:
1 Blocking measures shall be taken if the length of short side of vertical opening is less than 500mm; if the length of short side of vertical opening is larger than or equal to 500mm, protective railings with height not less than 1.2m shall be arranged at the suspending side, fine mesh safety vertical net or tool-typed breast board shall be adopted as enclosure, and toe board shall be arranged.
2 If the length of short side of non-vertical opening is 25mm~500mm, cover plate complying with the use requirements of bearing capacity shall be adopted, the cover plate shall be balanced during placement and prevented from displacement.
3 If the length of short side of non-vertical opening is 500mm~1,500mm, measures like covering cover plate or arranging protective railings shall be adopted and the cover plate or protective railings shall be firmly fixed.
4 If the length of short side of non-vertical opening is larger than or equal to 1,500mm, protective railings with height not less than 1.2m shall be arranged at the opening operation side, horizontal safety net shall be adopted to close the opening.
4.2.2 Protective door with height not less than 1.5m and bottom not greater than 50mm away from ground shall be set at elevator shaft opening, and toe board shall be set.
4.2.3 Horizontal safety net shall be arranged every 2 storeys (not greater than 10m) in elevator shaft before the construction of elevator. Isolation and protection facilities shall be set at the upper part of construction layer in elevator shaft.
4.2.4 Opening cover plate shall be able to bear concentrated load not less than 1kN and uniformly distributed load not less than 2kN/m2; cover plate with special requirements shall be designed separately.
4.2.5 For vertical openings leading to ground at positions like wall surface, with sill height lower than 800mm, and opening of frame structure after pouring concrete without masonry wall, protective railings shall be arranged in accordance with the requirements of edge-near protection.
Foreword i
1 General Provisions
2 Terms and Symbols
2.1 Terms
2.2 Symbols
3 Basic Requirements
4 Edge-near and Opening Operation
4.1 Edge-near Operation
4.2 Opening Operation
4.3 Protective Railings
5 Climbing and Hanging Operation
5.1 Climbing Operation
5.2 Hanging Operation
6 Operating Platform
6.1 General Requirements
6.2 Movable Operating Platform
6.3 Floor Type Operating Platform
6.4 Cantilevered Operating Platform
7 Cross Operation
7.1 General Requirements
7.2 Safety Precautions
8 Safety Nets in Building Construction
8.1 General Requirements
8.2 Erection of Safety Nets
Annex A Protective Railings Calculation for Design
Annex B Movable Operating Platform Calculation for Design
Annex C Cantilevered Operating Platform Calculation for Design
Explanation of Wording in This Code
List of Quoted Standards
