Detail of JTG 5120-2021

Introduction of JTG 5120-2021

1 General 1.0.1 for the standardization of highway bridge maintenance work, unified highway bridge maintenance technical standards, keep the bridge in normal use, the development of this specification. 1.0.2 This specification applies to the maintenance of highway bridges and culverts of all levels. There are special maintenance needs of the bridge, should develop special maintenance technical procedures. 1.0.3 highway bridge maintenance should follow the "prevention and control, scientific maintenance, safe operation, to ensure smooth" principle, and should meet the following requirements: 1 to ensure structural integrity, neat and tidy appearance and ancillary facilities complete and intact. 2 Equipped with the necessary testing and maintenance equipment and facilities. 3 actively and steadily adopt advanced inspection equipment, maintenance techniques and scientific management methods. 4 Keep abreast of changes in the technical condition of bridges and culverts and take corresponding maintenance countermeasures. 5Effectively carry out preventive maintenance to ensure structural durability. 6Ensure the safety of maintenance operations and reduce the impact on traffic. 7 Pay attention to resource conservation and environmental protection. 2 Terminology 2.0.1 Bridge technical condition A comprehensive technical index of the components or elements of a bridge structure, reflecting the degree of structural integrity, safety and perfection of its use. 2.0.2 initial inspection The first comprehensive inspection of the technical condition of a bridge structure and its ancillary components after a newly constructed or altered bridge has been put into use, the results of which are the benchmark for later bridge inspection and assessment work. 2.0.3 daily inspection Daily inspection and visual inspection of the bridge deck and above, of the bridge components, abnormal structural displacements and the bridge safety zone. 2.0.4 Routine inspection A periodic inspection of the bridge deck system, superstructure, substructure and ancillary facilities using visual inspection combined with auxiliary tools, close to the bridge structure. 3 Bridge inspection, monitoring and assessment 3.1 General provisions 3.1.1 Highway bridge maintenance inspection grade shall be divided into I, II, II, grading standards shall be in accordance with the following provisions: 1 single hole span diameter greater than 150m of special bridges, particularly important bridge maintenance inspection level for I level. 2 single hole span diameter less than or equal to 150m special bridge, bridge, as well as highway or -, the second level of highway in the bridge, small bridge maintenance inspection level for II level. 3 three, four highways on the bridge, small bridge maintenance inspection level I. 4 The technical condition of large, medium and small bridges rated as class 3 should be raised one level for inspection. 5 technical condition assessment for 4 types of bridges in the reinforcement and repair before the I level should be inspected. 3.1.2 Bridge inspection shall be divided into initial inspection, daily inspection, regular inspection, periodic inspection and special inspection. 3.1.3 Bridges with a maintenance inspection rating of Class I should be fitted with a structural monitoring system to monitor the structural condition and response under all types of external loads, and the monitoring results should be compared and analysed with the bridge inspection results on a regular basis. 3.1.4 Bridge assessment should include technical condition assessment and suitability assessment. 4 Bridge maintenance and repair 4.1 General provisions 4.1.1 Bridge maintenance work shall be carried out in conjunction with the maintenance inspection level of the bridge, and the corresponding maintenance and repair plan shall be formulated and treated in a timely manner for any defects found during the bridge inspection. 4.1.2 Bridge maintenance shall meet the following requirements: 1 Neat and tidy appearance of the bridge. 2 structure without damage, no abnormal deformation, good stability. 3 bridge deck pavement solid and smooth, vertical and horizontal slope moderate, smooth bridge head. 4 bridge deck system components, bearings and ancillary facilities in good condition, normal function, reasonable layout. 5 foundation without erosion. 4.1.3 If the bridge is found to have insufficient load-bearing capacity, stiffness or stability, it shall be repaired and strengthened in accordance with the relevant technical standards, specifications and procedures. 4.1.4 Bridges shall be provided with access or facilities for observation, inspection and maintenance. 4.1.5 Where the protective layer of reinforcement cannot meet the requirements of the Code or where the bridge is in a corrosive environment, additional anti-corrosion measures should be provided to ensure 4.1.4 Bridges shall be provided with access or facilities for observation, inspection and maintenance. 5 Bridge disaster prevention and repair 5.1 General provisions 5.1.1 A comprehensive analysis shall be carried out to assess the bridge's resistance to disasters based on the hydrogeological conditions, meteorological characteristics and operational conditions of the bridge, combined with technical inspections of the bridge. 5.1.2 During periods of frequent natural disasters such as floods, typhoons, snowstorms and freezing temperatures, safety hazard inspections should be strengthened. Traffic control should be implemented when necessary and public announcement information should be issued in a timely manner. When there are natural disaster hazards such as falling rocks and landslides in the vicinity of the bridge area, they should be reported to the competent authorities in a timely manner and appropriate measures should be taken to deal with them. 5.1.3 Important bridges and bridges prone to disasters should have an emergency plan and be equipped with the necessary emergency personnel, repair materials and mechanical equipment. 5.1.4 After a bridge has been affected, the damage to all bridge components should be fully inspected and the necessary temporary support measures should be taken for bridges that are likely to fracture, collapse and become unstable. At the same time, a vehicle detour should be arranged, and the organisation of repair of the right-of-way bridge and right-of-way should be carried out to restore traffic as soon as possible. 6 Overweight vehicles crossing bridges 6.1 General provisions 6.1.1 The necessary technical and management measures shall be taken for overweight vehicles crossing bridges. 6.1.2 Technical measures for overweight vehicles crossing bridges shall comply with the following provisions: 1 The strength, stiffness and stability of the bridge structure shall be tested according to the actual load of the overweight vehicle, based on the results of the site survey and the technical data of the bridge. 2 Load tests shall be carried out, if necessary, to determine the load carrying capacity of the bridge. 3 Bridges that cannot meet the needs of traffic should be strengthened and treated. 4 When more than one route is available, the route with good technical condition, high load-bearing capacity and low reinforcement cost should be selected. 7 Inspection, maintenance and repair of culverts 7.1 General provisions 7.1.1 The maintenance of culverts shall comply with the following provisions: 1 Normal function, smooth drainage and proper discharge; 2 All components and ancillary structures are in good condition; 3 The surface of the culvert is clean and free from water leakage. 7.1.2 The culvert maintenance work shall include frequent and regular inspection, daily maintenance, repair, reinforcement and alteration. 7.1.3 When the culvert needs to be excavated for maintenance and reinforcement, the work shall be carried out according to the requirements of the current "Highway Maintenance Safety Practice" (JTG H30). 7.2 Culvert inspection 7.2.1 Regular inspection shall comply with the following provisions: 1 Regular inspection shall be carried out not less than once a quarter, and the frequency of inspection shall be increased during the flood season and before and after snow and ice. 8 Technical management 8.1 General provisions 8.1.1 Highway bridge and culvert maintenance should strengthen technical management, strictly comply with and implement the technical standards, norms and regulations of highway bridge and culvert, establish and improve the technical management system of bridge and culvert maintenance, improve the acceptance of bridge and culvert inspection and assessment results and maintenance project decision-making, design, construction, acceptance and post-evaluation mechanism, improve the quality of highway bridge and culvert maintenance and service level. 8.1.2 The technical management of highway bridge and culvert maintenance shall include technical file management, database management, information management, etc. 8.1.3 should follow the principle of "unified management, graded responsibility", establish and improve the technical file management system of bridge culverts, standardize the technical file management of bridge culverts. 8.1.4 should be in accordance with the "highway bridge maintenance management system" requirements, with dedicated personnel responsible for bridge maintenance technical management, should be configured bridge maintenance equipment, instruments and information management needs of computer hardware and software systems, network facilities and data acquisition and other equipment. 8.1.5 Medium bridges and above shall set up information disclosure signs, and achieve "one bridge one sign". Bridge information shall include the bridge name, route number, route name, bridge type, central pile number, maintenance unit, management unit, supervision unit, contact information, etc. Appendix A Bridge Basic Condition Card Appendix B Bridge Initial Inspection Record Form Appendix C Bridge Periodic Inspection Record Form Appendix D Bridge Frequent Inspection Record Form Appendix E Bridge Special Inspection Record Form Appendix F Culvert Recurring Inspection Record Form Appendix G Culvert Basic Condition Card Appendix H Culvert Periodic Inspection Record Sheet Explanation of terms used in this specification

Contents of JTG 5120-2021

1 General 2 Terminology 3 Bridge inspection, monitoring and assessment 4 Bridge maintenance and repair 5 Bridge disaster prevention and repair 6 Overweight vehicles crossing bridges 7 Inspection, maintenance and repair of culverts 8 Technical management Appendix A Bridge Basic Condition Card Appendix B Bridge Initial Inspection Record Form Appendix C Bridge Periodic Inspection Record Form Appendix D Bridge Frequent Inspection Record Form Appendix E Bridge Special Inspection Record Form Appendix F Culvert Recurring Inspection Record Form Appendix G Culvert Basic Condition Card Appendix H Culvert Periodic Inspection Record Sheet Explanation of terms used in this specification