1 General
1.0.1 In order to standardize the maintenance of highway cable-stayed structure system bridges, to improve the level of maintenance technology and operational safety and security, this specification is formulated.
1.0.2 This specification applies to the maintenance of highway cable-stayed bridges and suspension bridges. Public-railway cable-stayed bridges and suspension bridges of the road part can refer to the provisions of this specification.
1.0.3 Highway cable-stayed structure system bridge maintenance work should implement the "planning guidance, prevention-oriented, prevention and control, fine and strict" policy, to ensure the safety, durability and comfort of the bridge.
Article Description
Bridges with cable-stayed structures are characterised by large spans, low overall structural stiffness, high deformation, many fragile elements, complex structures and high operation and maintenance costs. Some important load-bearing elements are difficult to repair and replace once damaged, so the scientific and rational maintenance of such bridges directly determines their service life and maintenance costs. Existing experience shows that under the guidance of scientific maintenance planning, the adoption of a prevention-oriented and combined prevention and control strategy, the establishment of a strict inspection and monitoring system combined with refined routine maintenance and timely maintenance works, is an effective way to ensure the structural safety of these bridges and to reduce the whole life cycle cost of use.
2 Terminology
2.0.1 Cable-supported bridge
A bridge consisting of a combination of towers, girders and cables, where the cables are the main load-bearing structure.
2.0.2 bridge preventive maintenance
A bridge that has good overall performance but is slightly diseased, and is pre-protected in order to slow down the rapid decay of performance and extend its service life.
2.0.3 Bridge repair maintenance
The functional, structural repair or periodic replacement of a bridge that is significantly diseased or partially out of service, in order to restore its technical condition, including major, medium and minor repairs.
2.0.4 Bridge emergency maintenance
The temporary repair and maintenance of a bridge to restore its safety capacity as soon as possible after the bridge has been damaged, interrupted or has become a major safety hazard due to unexpected circumstances. It is a temporary maintenance measure to ensure accessibility.
3 Inspection, monitoring and assessment
3.1 General provisions
3.1.1 The inspection of bridges with cable-stayed structures shall be divided into initial inspection, daily inspection, regular inspection, periodic inspection and special inspection.
3.1.2 The inspection items, methods and frequency of each type of inspection for bridges with cable-stayed structures shall be specified according to the importance of the different components, the difficulty of maintenance and vulnerability and in conjunction with the age of the bridge and the assessment of the technical condition of the bridge. For special designs or bridge components not covered by the current standards, inspection indicators, methods and assessment criteria shall be specified in accordance with the design documents prior to the initial inspection.
4 Maintenance strategy
4.1 General provisions
4.1.1 The maintenance strategy for bridges of the cable-stayed highway system shall be determined in accordance with the principles of strengthening daily maintenance, active preventive maintenance and effective restoration maintenance.
4.1.2 The bridge maintenance plan shall be reasonably prepared and adjusted according to the structural characteristics, operating environment and deterioration of the structural performance of the specific bridge, combined with the initial inspection results and subsequent annual inspections. The maintenance plan shall comply with the following provisions:
l The content of the plan shall be adapted to the actual needs of bridges of the highway cable structure system, mainly including bridge maintenance system and file planning, bridge inspection planning, structural maintenance planning, mechanical and electrical equipment maintenance planning, bridge emergency plan planning, maintenance funds planning period estimation, etc.
2 The planning should adhere to the principle of optimal cost of maintenance over the whole life cycle.
3 The planning period should not be less than 20 years, with a focus on the near term (3-5 years) and medium term (10-15 years), and it is advisable to evaluate and revise the maintenance plan every 3-5 years according to the actual situation.
5 Maintenance of cable-stayed bridges
5.1 Cable-stayed bridges
5.1.1 The maintenance of cable-stayed bridges shall be in accordance with the following provisions:
1 The cable should be in good condition, no defects, normal function, strength, force, line should meet the design requirements.
2 The cable should not be attached to billboards, flags, ribbons and other accessories that are not related to the maintenance of the function of the cable, and when it is necessary to install additional ones due to landscape lighting, a special assessment should be made before installation.
3 When carrying out cable force measurement, monitoring or maintenance and repair, damage to the cable sheath should be avoided.
4Two main types of diagonal cables are parallel wire cables and strand cables, each with matching anchorages, and their protective layers are also different. Therefore, maintenance and repair should be carried out in combination with the respective construction characteristics.
5.1.2 The daily maintenance of the cable shall focus on the cleanliness of the cable elements and shall be carried out no less than once a quarter.
5.1.3 The cleaning of the diagonal cable elements shall be based on the cleaning of the cable anchorage system and the surrounding environment, with regular cleaning of debris and standing water in the vicinity of the anchorage system; the anchorages and the sheathing shall be kept clean and dry.
Article description
The anchorage system of inclined cables is an area prone to disease, prone to water accumulation and difficult to inspect, and the forces in this area are complex. Therefore, it is important to clean up the debris and water in the vicinity of the anchorage system in time to ensure that the cable-stayed wire and its anchorage system are in a dry and clean environment to avoid corrosion diseases.
6 Maintenance of suspension bridges
6.1 Main cable system
6.1.1 The maintenance of the main cable system of suspension bridges shall comply with the following provisions:
1 main cable system maintenance should maintain the normal function of the components and ancillary facilities, no defects, no corrosion. 2 main cable line shape should meet the design requirements, protection is intact, the surface is smooth, steel wire to keep dry, anchor head, anchor rod, tie rod, exposed rope strands without water, water seepage.
3 The cable clamp should be free from slippage, the tightening bolt force should be kept within the range of the cable clamp anti-slip requirements, and the nut should be prevented from rusting and being unable to be adjusted.
4 The main saddle should be stable, and the loose saddle (sleeve) should be able to ensure smooth shifting, and the offset should be within the design allowance.
5 The deviation of the cable force of the boom (rope, cable) shall be within the design allowance and the protection shall be intact. 6 If the main cable is protected by a dehumidification system, the internal relative humidity shall not be greater than 50%.
6.1.2 The daily maintenance of the main cable system shall be mainly clean and shall comply with the following provisions:
1 Main cable and protective layer, rope clamps, boom (rope, rope), rope saddle, handrail rope and cable sleeve and other external surfaces of the cleaning not less than 1 time per year.
2 The cleaning of the main cable system components should be the main content of the work of each component and the surrounding environment, regular cleaning of debris, water, snow, dust, dirt and oil stains.
Article description
The main cause of damage to the main cable and boom (rope and cable) system is rust and corrosion, such as damage to the protective layer, surface coating or gap filler leading to rain or moisture intrusion caused by rust and corrosion, etc. Therefore, the main cable system daily maintenance focus on ensuring that the steel wire from moisture and other external harmful substances erosion and ensure the appearance of clean, beautiful. Frequent or regular cleaning is the basic prerequisite for maintaining its durability.
7 Maintenance of the main beam
7.1 Steel main beams
7.1.1 The maintenance of steel main girders of bridges with cable-structured systems shall be in accordance with the following provisions: l The steel main girders shall be clean and free from water inside and outside.
2 The coating of each member of the steel girder shall be complete and the protective properties shall meet the design requirements.
3 The main steel girder shall be smoothly aligned, the members (including bolting and welding) shall be in good condition, and the strength, stiffness and stability shall meet the design requirements.
4 No abnormal vibration of the steel main beam.
5 Relative humidity in enclosed spaces such as steel box girders is not greater than 50%. Article Description
This article sets out the general requirements for the maintenance of all-steel main girders of bridges with cable-structure systems. According to the provisions of Article 1.0.5 of this specification, the specific content of this section only includes the anchorage part of the steel main girders connected to the main cables and tension (suspension) cables, such as steel anchor boxes, anchor tie plates, self-anchored suspension bridge anchor girders, etc.
5 The requirement for humidity in enclosed spaces is for cases where a dehumidification system is installed.
7.1.2 Daily maintenance of the anchorage area of the steel main girder cables and cables is advisable to clean the internal and external surfaces of the structure according to the inspection results, which should be done not less than twice a year and once a quarter for the parts exposed to the bridge deck.
8 Maintenance of the bridge deck system and ancillary facilities
8.1 Bridge deck pavement
8.1.1 highway cable structure system bridge deck pavement maintenance shall comply with the following provisions:
1 should be strictly controlled pavement layer thickness. When causing load changes, should be carried out after a special assessment before implementation.
2 bridge deck pavement appears regular or serious cracks, bulging, rutting, pushing and other diseases, after the occurrence of fire, chemical corrosion and other special events, or before the implementation of maintenance should be timely special inspection assessment.
3 After completing the restorative maintenance of the paving and meeting the acceptance criteria, preventive maintenance can be implemented simultaneously. Article Description:
I cable-structure system bridge deck paving relative weight or thickness changes will affect and change the main beam alignment and force conditions, may have an impact on the bridge safety and use performance. Therefore, the thickness of the pavement should be strictly controlled in the pavement maintenance and kept in line with the original design as far as possible. It is not recommended to carry out preventive maintenance of the sealing layer, overlay, etc. too thick; in the milling and resurfacing programme, if the paving thickness and relative weight of the material differs from the original design, the bridge structure should be tested to analyse the impact of the change in permanent load and to assess the impact on the height of the bridge parapet.
9 Technical management of maintenance
9.1 General provisions
9.1.1 The maintenance of bridges and ancillary facilities of the highway cable-stayed structure system shall be strengthened in accordance with the requirements of the relevant standards. Where a bridge crosses a navigation channel, the maintenance of navigation aids and anti-collision facilities attached to the bridge shall also be strengthened.
9.1.2 The administrative leader and specific technical personnel responsible for the technical management of the maintenance of bridges of highway cable-structure system shall be clearly defined, and the scientific configuration of maintenance professionals and technicians shall be constructed to build a talent training mechanism and establish a stable and professional maintenance technical team.
9.1.3 Special maintenance management funds shall be arranged according to individual bridges and maintenance operation categories, and the technical condition of bridges shall be accurately and timely grasped according to relevant regulations.
9.1.4 Where diseases and safety hazards exist, the maintenance and management unit shall promptly commission professional institutions to propose repair and reinforcement plans or maintenance countermeasures, and organise their implementation according to the prescribed procedures after passing the relevant examination.
9.1.5 The mechanised maintenance and rapid repair capacity of bridges with highway cable-structure system shall be gradually enhanced, and fast, convenient and durable techniques shall be encouraged and preventive maintenance shall be actively implemented.
9.1.6 Modern information technology should be used to establish a maintenance information system that meets its own characteristics.
Appendix A Bridge Basic Condition Card
Appendix B Normative Inspection Form
Appendix C Open cable inspection methods for suspension bridge main cables
Explanation of terms used in this specification
1 General
2 Terminology
3 Inspection, monitoring and assessment
4 Maintenance strategy
5 Maintenance of cable-stayed bridges
6 Maintenance of suspension bridges
7 Maintenance of the main beam
8 Maintenance of the bridge deck system and ancillary facilities
9 Technical management of maintenance
Appendix A Bridge Basic Condition Card
Appendix B Normative Inspection Form
Appendix C Open cable inspection methods for suspension bridge main cables
Explanation of terms used in this specification
Standard
JTG/T 5122-2021 Technical Specifications for Maintenance of Highway Cable-supported Bridge (English Version)
Standard No.
JTG/T 5122-2021
Status
valid
Language
English
File Format
PDF
Word Count
60000 words
Price(USD)
1800.0
Implemented on
2022-4-1
Delivery
via email in 1~5 business day
Detail of JTG/T 5122-2021
Standard No.
JTG/T 5122-2021
English Name
Technical Specifications for Maintenance of Highway Cable-supported Bridge
1 General
1.0.1 In order to standardize the maintenance of highway cable-stayed structure system bridges, to improve the level of maintenance technology and operational safety and security, this specification is formulated.
1.0.2 This specification applies to the maintenance of highway cable-stayed bridges and suspension bridges. Public-railway cable-stayed bridges and suspension bridges of the road part can refer to the provisions of this specification.
1.0.3 Highway cable-stayed structure system bridge maintenance work should implement the "planning guidance, prevention-oriented, prevention and control, fine and strict" policy, to ensure the safety, durability and comfort of the bridge.
Article Description
Bridges with cable-stayed structures are characterised by large spans, low overall structural stiffness, high deformation, many fragile elements, complex structures and high operation and maintenance costs. Some important load-bearing elements are difficult to repair and replace once damaged, so the scientific and rational maintenance of such bridges directly determines their service life and maintenance costs. Existing experience shows that under the guidance of scientific maintenance planning, the adoption of a prevention-oriented and combined prevention and control strategy, the establishment of a strict inspection and monitoring system combined with refined routine maintenance and timely maintenance works, is an effective way to ensure the structural safety of these bridges and to reduce the whole life cycle cost of use.
2 Terminology
2.0.1 Cable-supported bridge
A bridge consisting of a combination of towers, girders and cables, where the cables are the main load-bearing structure.
2.0.2 bridge preventive maintenance
A bridge that has good overall performance but is slightly diseased, and is pre-protected in order to slow down the rapid decay of performance and extend its service life.
2.0.3 Bridge repair maintenance
The functional, structural repair or periodic replacement of a bridge that is significantly diseased or partially out of service, in order to restore its technical condition, including major, medium and minor repairs.
2.0.4 Bridge emergency maintenance
The temporary repair and maintenance of a bridge to restore its safety capacity as soon as possible after the bridge has been damaged, interrupted or has become a major safety hazard due to unexpected circumstances. It is a temporary maintenance measure to ensure accessibility.
3 Inspection, monitoring and assessment
3.1 General provisions
3.1.1 The inspection of bridges with cable-stayed structures shall be divided into initial inspection, daily inspection, regular inspection, periodic inspection and special inspection.
3.1.2 The inspection items, methods and frequency of each type of inspection for bridges with cable-stayed structures shall be specified according to the importance of the different components, the difficulty of maintenance and vulnerability and in conjunction with the age of the bridge and the assessment of the technical condition of the bridge. For special designs or bridge components not covered by the current standards, inspection indicators, methods and assessment criteria shall be specified in accordance with the design documents prior to the initial inspection.
4 Maintenance strategy
4.1 General provisions
4.1.1 The maintenance strategy for bridges of the cable-stayed highway system shall be determined in accordance with the principles of strengthening daily maintenance, active preventive maintenance and effective restoration maintenance.
4.1.2 The bridge maintenance plan shall be reasonably prepared and adjusted according to the structural characteristics, operating environment and deterioration of the structural performance of the specific bridge, combined with the initial inspection results and subsequent annual inspections. The maintenance plan shall comply with the following provisions:
l The content of the plan shall be adapted to the actual needs of bridges of the highway cable structure system, mainly including bridge maintenance system and file planning, bridge inspection planning, structural maintenance planning, mechanical and electrical equipment maintenance planning, bridge emergency plan planning, maintenance funds planning period estimation, etc.
2 The planning should adhere to the principle of optimal cost of maintenance over the whole life cycle.
3 The planning period should not be less than 20 years, with a focus on the near term (3-5 years) and medium term (10-15 years), and it is advisable to evaluate and revise the maintenance plan every 3-5 years according to the actual situation.
5 Maintenance of cable-stayed bridges
5.1 Cable-stayed bridges
5.1.1 The maintenance of cable-stayed bridges shall be in accordance with the following provisions:
1 The cable should be in good condition, no defects, normal function, strength, force, line should meet the design requirements.
2 The cable should not be attached to billboards, flags, ribbons and other accessories that are not related to the maintenance of the function of the cable, and when it is necessary to install additional ones due to landscape lighting, a special assessment should be made before installation.
3 When carrying out cable force measurement, monitoring or maintenance and repair, damage to the cable sheath should be avoided.
4Two main types of diagonal cables are parallel wire cables and strand cables, each with matching anchorages, and their protective layers are also different. Therefore, maintenance and repair should be carried out in combination with the respective construction characteristics.
5.1.2 The daily maintenance of the cable shall focus on the cleanliness of the cable elements and shall be carried out no less than once a quarter.
5.1.3 The cleaning of the diagonal cable elements shall be based on the cleaning of the cable anchorage system and the surrounding environment, with regular cleaning of debris and standing water in the vicinity of the anchorage system; the anchorages and the sheathing shall be kept clean and dry.
Article description
The anchorage system of inclined cables is an area prone to disease, prone to water accumulation and difficult to inspect, and the forces in this area are complex. Therefore, it is important to clean up the debris and water in the vicinity of the anchorage system in time to ensure that the cable-stayed wire and its anchorage system are in a dry and clean environment to avoid corrosion diseases.
6 Maintenance of suspension bridges
6.1 Main cable system
6.1.1 The maintenance of the main cable system of suspension bridges shall comply with the following provisions:
1 main cable system maintenance should maintain the normal function of the components and ancillary facilities, no defects, no corrosion. 2 main cable line shape should meet the design requirements, protection is intact, the surface is smooth, steel wire to keep dry, anchor head, anchor rod, tie rod, exposed rope strands without water, water seepage.
3 The cable clamp should be free from slippage, the tightening bolt force should be kept within the range of the cable clamp anti-slip requirements, and the nut should be prevented from rusting and being unable to be adjusted.
4 The main saddle should be stable, and the loose saddle (sleeve) should be able to ensure smooth shifting, and the offset should be within the design allowance.
5 The deviation of the cable force of the boom (rope, cable) shall be within the design allowance and the protection shall be intact. 6 If the main cable is protected by a dehumidification system, the internal relative humidity shall not be greater than 50%.
6.1.2 The daily maintenance of the main cable system shall be mainly clean and shall comply with the following provisions:
1 Main cable and protective layer, rope clamps, boom (rope, rope), rope saddle, handrail rope and cable sleeve and other external surfaces of the cleaning not less than 1 time per year.
2 The cleaning of the main cable system components should be the main content of the work of each component and the surrounding environment, regular cleaning of debris, water, snow, dust, dirt and oil stains.
Article description
The main cause of damage to the main cable and boom (rope and cable) system is rust and corrosion, such as damage to the protective layer, surface coating or gap filler leading to rain or moisture intrusion caused by rust and corrosion, etc. Therefore, the main cable system daily maintenance focus on ensuring that the steel wire from moisture and other external harmful substances erosion and ensure the appearance of clean, beautiful. Frequent or regular cleaning is the basic prerequisite for maintaining its durability.
7 Maintenance of the main beam
7.1 Steel main beams
7.1.1 The maintenance of steel main girders of bridges with cable-structured systems shall be in accordance with the following provisions: l The steel main girders shall be clean and free from water inside and outside.
2 The coating of each member of the steel girder shall be complete and the protective properties shall meet the design requirements.
3 The main steel girder shall be smoothly aligned, the members (including bolting and welding) shall be in good condition, and the strength, stiffness and stability shall meet the design requirements.
4 No abnormal vibration of the steel main beam.
5 Relative humidity in enclosed spaces such as steel box girders is not greater than 50%. Article Description
This article sets out the general requirements for the maintenance of all-steel main girders of bridges with cable-structure systems. According to the provisions of Article 1.0.5 of this specification, the specific content of this section only includes the anchorage part of the steel main girders connected to the main cables and tension (suspension) cables, such as steel anchor boxes, anchor tie plates, self-anchored suspension bridge anchor girders, etc.
5 The requirement for humidity in enclosed spaces is for cases where a dehumidification system is installed.
7.1.2 Daily maintenance of the anchorage area of the steel main girder cables and cables is advisable to clean the internal and external surfaces of the structure according to the inspection results, which should be done not less than twice a year and once a quarter for the parts exposed to the bridge deck.
8 Maintenance of the bridge deck system and ancillary facilities
8.1 Bridge deck pavement
8.1.1 highway cable structure system bridge deck pavement maintenance shall comply with the following provisions:
1 should be strictly controlled pavement layer thickness. When causing load changes, should be carried out after a special assessment before implementation.
2 bridge deck pavement appears regular or serious cracks, bulging, rutting, pushing and other diseases, after the occurrence of fire, chemical corrosion and other special events, or before the implementation of maintenance should be timely special inspection assessment.
3 After completing the restorative maintenance of the paving and meeting the acceptance criteria, preventive maintenance can be implemented simultaneously. Article Description:
I cable-structure system bridge deck paving relative weight or thickness changes will affect and change the main beam alignment and force conditions, may have an impact on the bridge safety and use performance. Therefore, the thickness of the pavement should be strictly controlled in the pavement maintenance and kept in line with the original design as far as possible. It is not recommended to carry out preventive maintenance of the sealing layer, overlay, etc. too thick; in the milling and resurfacing programme, if the paving thickness and relative weight of the material differs from the original design, the bridge structure should be tested to analyse the impact of the change in permanent load and to assess the impact on the height of the bridge parapet.
9 Technical management of maintenance
9.1 General provisions
9.1.1 The maintenance of bridges and ancillary facilities of the highway cable-stayed structure system shall be strengthened in accordance with the requirements of the relevant standards. Where a bridge crosses a navigation channel, the maintenance of navigation aids and anti-collision facilities attached to the bridge shall also be strengthened.
9.1.2 The administrative leader and specific technical personnel responsible for the technical management of the maintenance of bridges of highway cable-structure system shall be clearly defined, and the scientific configuration of maintenance professionals and technicians shall be constructed to build a talent training mechanism and establish a stable and professional maintenance technical team.
9.1.3 Special maintenance management funds shall be arranged according to individual bridges and maintenance operation categories, and the technical condition of bridges shall be accurately and timely grasped according to relevant regulations.
9.1.4 Where diseases and safety hazards exist, the maintenance and management unit shall promptly commission professional institutions to propose repair and reinforcement plans or maintenance countermeasures, and organise their implementation according to the prescribed procedures after passing the relevant examination.
9.1.5 The mechanised maintenance and rapid repair capacity of bridges with highway cable-structure system shall be gradually enhanced, and fast, convenient and durable techniques shall be encouraged and preventive maintenance shall be actively implemented.
9.1.6 Modern information technology should be used to establish a maintenance information system that meets its own characteristics.
Appendix A Bridge Basic Condition Card
Appendix B Normative Inspection Form
Appendix C Open cable inspection methods for suspension bridge main cables
Explanation of terms used in this specification
Contents of JTG/T 5122-2021
1 General
2 Terminology
3 Inspection, monitoring and assessment
4 Maintenance strategy
5 Maintenance of cable-stayed bridges
6 Maintenance of suspension bridges
7 Maintenance of the main beam
8 Maintenance of the bridge deck system and ancillary facilities
9 Technical management of maintenance
Appendix A Bridge Basic Condition Card
Appendix B Normative Inspection Form
Appendix C Open cable inspection methods for suspension bridge main cables
Explanation of terms used in this specification
