1 General
1.0.1 In order to adapt to the development needs of road maintenance, standardize the preventive maintenance of highway asphalt pavement, improve the technical level of asphalt pavement preventive maintenance, develop this specification.
1.0.2 This specification applies to all levels of highway asphalt pavement preventive maintenance.
1.0.3 should carry out the prevention-oriented, prevention and control combined with the road maintenance policy, and actively implement asphalt pavement preventive maintenance. On the premise of satisfying the pavement performance, safe and reliable, economical and applicable, convenient construction and green preventive maintenance technology should be selected.
1.0.4 Preventive maintenance of asphalt pavement should actively and steadily adopt new technologies, new materials, new techniques and new equipment, and if there is no national or industry standard basis, experimental research, engineering inspection and full demonstration should be conducted before large-scale application.
1.0.5 In addition to the provisions of this specification, the preventive maintenance of asphalt pavements shall also conform to the provisions of the relevant national and industry standards in force.
2 Terminology and symbols
2.1 Terminology
2.1.1 Asphalt pavement preventive maintenance asphalt pavement preventive maintenance
Pavement maintenance measures taken in advance to prevent the occurrence of disease or the extension of minor disease, to slow down the decay of pavement performance and to enhance service functions.
Article description
According to the Measures for the Management of Road Maintenance Works, preventive maintenance refers to the preemptive protective works taken to delay the rapid deterioration of performance and prolong the service life of a road with good overall performance but with minor defects. It is important to note that works where preventive maintenance techniques are used are not necessarily preventive maintenance works. In contrast to other pavement maintenance techniques, the basic feature of pavement preventive maintenance techniques is the thin thickness, which generally does not exceed 40mm.
3 Basic requirements
3.1 General requirements
3.1.1 Preventive maintenance planning for asphalt pavements shall be carried out in accordance with the scientific decision-making requirements for road maintenance.
3.1.2 An annual plan for preventive maintenance of asphalt pavements shall be prepared, taking into account all factors, determining the investment and scale of preventive maintenance, and actively implementing preventive maintenance on the road sections that meet the conditions for implementation of preventive maintenance.
3.1.3 Preventive maintenance of asphalt pavement shall include basic information collection, road condition survey and evaluation, decision making, design, construction, project quality control, post-evaluation and other work contents.
4 Preventive maintenance decision making
4.1 General provisions that
4.1.1 Scientific preventive maintenance decisions shall be made based on road condition inspection data and checks, maintenance funds, maintenance objectives, etc.
Article description
Scientific maintenance decision making is a prerequisite for ensuring maintenance effectiveness and maintenance economy, and is also an important basis for the design of maintenance works, which is very crucial. Maintenance decisions are generally made by road maintenance management departments or road operating enterprises, or by consultancy organisations commissioned by them.
4.1.2 The selection of preventive maintenance techniques should follow the following principles:
1 Targeted techniques should be selected according to the purpose of maintenance and the characteristics of the disease, etc.
2 Preference shall be given to techniques that have been proven in local engineering practice, are experienced in application and have good implementation results.
3 When applied to special sections such as urban transit sections, sections with restricted clearances and tunnels, the applicability of the technology should be confirmed.
4 When multiple preventive maintenance techniques are applied at the same time and there is no experience to judge the advantages and disadvantages, a technical and economic comparison should be made.
5 Classification of preventive maintenance techniques
5.1 General provisions
5.1.1 Preventive maintenance techniques for asphalt pavements can be classified into different types such as sealing, overlay and in-situ thermal regeneration.
5.1.2 Material innovation, equipment innovation and process innovation of preventive maintenance techniques shall be actively carried out to continuously improve their technical performance, construction efficiency and economy and to reduce the impact of maintenance construction on traffic.
Article description
In recent years, preventive maintenance of asphalt pavements in China has continued to innovate and new technologies have emerged. For example, the fibre seal layer made by adding a layer of fibres and modified emulsified asphalt on top of the crushed stone seal layer, the composite seal layer made by the combination of crushed stone seal layer or fibre seal layer plus micro-surface area, crushed stone seal layer plus thin slurry seal layer; and then for example, the use of special construction equipment to sequentially sprinkle/spread the interlayer interface agent, emulsified high viscosity asphalt, aggregate, second emulsified high viscosity asphalt, surface protection agent and other materials into the original pavement in multiple layers simultaneously "Although the new technologies vary, they are generally based on the technologies specified in this specification. Material improvements, process improvements or combinations of different technologies on top of each other provide more technical options for preventive maintenance.
6 Design of preventive maintenance works
6.1 General provisions
6.1.1 The design of preventive maintenance works for asphalt pavements shall include investigation and testing and evaluation, technical design, material composition design, traffic organisation design, etc.
6.1.2 The design of preventive maintenance works shall conform to the relevant provisions of the current Specification for the Design of Asphalt Pavement Maintenance of Highways (JTG 5421), follow the principle of sectional design and classification treatment, and carry out the design as a design unit.
6.1.3 Detailed investigation and testing of the technical condition of the pavement shall be carried out as required, and the causes of pavement distress shall be accurately judged and analysed.
6.1.4 One-stage construction drawing design is appropriate for preventive maintenance works. Dynamic design should be implemented, and the design should be changed in time when the technical condition of the pavement, material condition, etc. change significantly compared with the design phase.
7 Grouting and jointing
7.1 General provisions
7.1.1 The performance of the sealant for grouting and the adhesive for sticking joints shall meet the requirements of the design and the relevant specifications.
7.1.2 The construction site should be cleaned up before grouting and jointing to ensure that the cracks and the surrounding area are dry and clean to avoid bonding failure.
There should be no loose, gnawed edges in the slotted construction.
7.1.3 Slotting and grouting is recommended for transverse cracks in pavements, and sticking is recommended for longitudinal cracks in pavements.
7.1.4 Grouting and jointing should be carried out in temperatures above 5 "C and not in rainy weather.
7.1.5 Where not provided for in this specification, the relevant provisions of the current Technical Specification for Maintenance of Asphalt Pavements on Highways (JTG5142) shall apply.
8 Fog seal layer
8.1 General provisions
8.1.1 The fog seal layer shall be selected from emulsified asphalt or reductant materials according to the original pavement condition.
Article Description:
Reducing agent materials are mainly composed of saturated aromatic hydrocarbons and can improve the performance of ageing asphalt. Emulsified asphalt fog seal materials consist of emulsified asphalt, modifiers, additives and fine aggregates; depending on the situation, the emulsified asphalt, modifiers and additives can be mixed together in advance to form an emulsified asphalt mixture.
9 Gravel seal and fibre seal
9.1 General provisions
9.1.1 The crushed stone seal shall be constructed at an ambient temperature above 10°C and shall be applied in a dry condition on the road surface.
Article Description
When the crushed stone seal binder is emulsified bitumen, the road surface may be wet but there must be no water.
9.1.2 According to different construction techniques, crushed stone seal can be divided into synchronous crushed stone seal and asynchronous crushed stone seal. According to the different particle sizes of the aggregates, the crushed stone seal can be divided into sand type, fine type and medium type, and the corresponding maximum particle sizes of the crushed stone are 5mm, 10mm and 15mm respectively.
9.1.3 Aggregate mud content and needle flake content shall be strictly controlled in gravel seal.
9.1.4 Material requirements, design, construction and construction quality control of fibre sealing layer shall conform to the relevant provisions of the current Technical Specification for Maintenance of Asphalt Pavements on Highways (JTG 5142).
10 Micro-surface and thin slurry sealing layer
10.1 General provisions
10.1.1 Micro-surfacing can be divided into MS-2, MS-3 and MS-4 types according to the grade of minerals, and into two grades A and B according to the performance. Grade A microsurfacing is recommended for tunnel road surfaces, night construction and sections with higher performance requirements.
Article Description
Compared with the Technical Specification for Maintenance of Asphalt Pavements on Highways (JTG 5142-2019) and the Technical Guideline for Microsurfacing and Diluted Slurry Seal, this article distinguishes between Class A and Class B microsurfacing, and also adds the MS-4 type of grading.
10.1.2 Diluted slurry seal can be divided into ES-1, ES-2 and ES-3 types according to the grade of mineral materials, and into fast open traffic type and slow open traffic type according to the speed of open traffic.
10.1.3 The temperature during the construction and maintenance period of the micro-surface and thin slurry seal shall be higher than 10C.
11 Thin overlays and ultra-thin overlays
11.1 General provisions
11.1.1 SMA-10/13, AC-10/13, OGFC hot mix or warm mix asphalt mixtures matching the thickness of the pavement may be used for thin overlays; the binder shall be high viscosity modified asphalt, polymer modified asphalt, rubber modified asphalt or road petroleum asphalt depending on the application.
Article description
In engineering practice, SMA and AC type mixes are used in thin layer overlays, while OGFC type mixes are used to achieve drainage and noise reduction effects. The Technical Specification for Maintenance of Asphalt Pavements (JTG 5142-2019) also gives a BPA-type mix for a skeleton-void type gradation with a void ratio of 10-15%, which is relatively little used in engineering practice.
11.1.2 ultra-thin overlay can be used to match the thickness of the pavement void type ultra-thin overlay UTO-5/10/13 type and dense ultra-thin overlay UTOD-5, SMA-5/10, AC-5/10 type of hot mix asphalt mixture or warm mix asphalt mixture, binder should be selected according to the use of high viscosity modified asphalt, polymer modified asphalt, rubber modified asphalt, Sticky layer should be used SBS modified emulsified asphalt, high viscosity modified emulsified asphalt or non-stick wheel modified emulsified asphalt.
12 Sealer coverings
12.1 General provisions
12.1.1 The construction environment and temperature requirements of the gravel seal, thin layer cover and ultra-thin cover shall conform to the requirements of sections 9.1 and 11.1 of this specification.
12.1.2 After the construction of the crushed stone seal is completed, timely rolling is desirable and excess crushed stone shall be recycled before overlaying or sealing.
13 Post preventive maintenance assessment
13.0.1 It is desirable to establish a post-preventive maintenance assessment mechanism for asphalt pavements, which may achieve all or some of the following objectives through post-assessment, as required:
1 Summarise the effectiveness of preventive maintenance techniques and develop a realistic list of pavement maintenance techniques;
2 To summarise the complete chain of evidence of pavement distress;
3 Modify pavement preventive maintenance decision making methods;
4 Establish a realistic decay model of pavement conditions to determine the expected life of preventive maintenance techniques;
5 Develop a practical guide to pavement preventive maintenance techniques.
Appendix A Maintenance Benefit Cost Analysis Methodology
Appendix B Initial Wear Loss Test for Mix Maintenance at Micro Surface
1 General
2 Terminology and symbols
3 Basic requirements
4 Preventive maintenance decision making
5 Classification of preventive maintenance techniques
6 Design of preventive maintenance works
7 Grouting and jointing
8 Fog seal layer
9 Gravel seal and fibre seal
10 Micro-surface and thin slurry sealing layer
11 Thin overlays and ultra-thin overlays
12 Sealer coverings
Appendix A Maintenance Benefit Cost Analysis Methodology
Appendix B Initial Wear Loss Test for Mix Maintenance at Micro Surface
Standard
JTG/T 5142-01-2021 Technical Specifications for Preventive Maintenance of Highway Asphalt Pavement (English Version)
Standard No.
JTG/T 5142-01-2021
Status
valid
Language
English
File Format
PDF
Word Count
30000 words
Price(USD)
900.0
Implemented on
2021-12-1
Delivery
via email in 1~5 business day
Detail of JTG/T 5142-01-2021
Standard No.
JTG/T 5142-01-2021
English Name
Technical Specifications for Preventive Maintenance of Highway Asphalt Pavement
1 General
1.0.1 In order to adapt to the development needs of road maintenance, standardize the preventive maintenance of highway asphalt pavement, improve the technical level of asphalt pavement preventive maintenance, develop this specification.
1.0.2 This specification applies to all levels of highway asphalt pavement preventive maintenance.
1.0.3 should carry out the prevention-oriented, prevention and control combined with the road maintenance policy, and actively implement asphalt pavement preventive maintenance. On the premise of satisfying the pavement performance, safe and reliable, economical and applicable, convenient construction and green preventive maintenance technology should be selected.
1.0.4 Preventive maintenance of asphalt pavement should actively and steadily adopt new technologies, new materials, new techniques and new equipment, and if there is no national or industry standard basis, experimental research, engineering inspection and full demonstration should be conducted before large-scale application.
1.0.5 In addition to the provisions of this specification, the preventive maintenance of asphalt pavements shall also conform to the provisions of the relevant national and industry standards in force.
2 Terminology and symbols
2.1 Terminology
2.1.1 Asphalt pavement preventive maintenance asphalt pavement preventive maintenance
Pavement maintenance measures taken in advance to prevent the occurrence of disease or the extension of minor disease, to slow down the decay of pavement performance and to enhance service functions.
Article description
According to the Measures for the Management of Road Maintenance Works, preventive maintenance refers to the preemptive protective works taken to delay the rapid deterioration of performance and prolong the service life of a road with good overall performance but with minor defects. It is important to note that works where preventive maintenance techniques are used are not necessarily preventive maintenance works. In contrast to other pavement maintenance techniques, the basic feature of pavement preventive maintenance techniques is the thin thickness, which generally does not exceed 40mm.
3 Basic requirements
3.1 General requirements
3.1.1 Preventive maintenance planning for asphalt pavements shall be carried out in accordance with the scientific decision-making requirements for road maintenance.
3.1.2 An annual plan for preventive maintenance of asphalt pavements shall be prepared, taking into account all factors, determining the investment and scale of preventive maintenance, and actively implementing preventive maintenance on the road sections that meet the conditions for implementation of preventive maintenance.
3.1.3 Preventive maintenance of asphalt pavement shall include basic information collection, road condition survey and evaluation, decision making, design, construction, project quality control, post-evaluation and other work contents.
4 Preventive maintenance decision making
4.1 General provisions that
4.1.1 Scientific preventive maintenance decisions shall be made based on road condition inspection data and checks, maintenance funds, maintenance objectives, etc.
Article description
Scientific maintenance decision making is a prerequisite for ensuring maintenance effectiveness and maintenance economy, and is also an important basis for the design of maintenance works, which is very crucial. Maintenance decisions are generally made by road maintenance management departments or road operating enterprises, or by consultancy organisations commissioned by them.
4.1.2 The selection of preventive maintenance techniques should follow the following principles:
1 Targeted techniques should be selected according to the purpose of maintenance and the characteristics of the disease, etc.
2 Preference shall be given to techniques that have been proven in local engineering practice, are experienced in application and have good implementation results.
3 When applied to special sections such as urban transit sections, sections with restricted clearances and tunnels, the applicability of the technology should be confirmed.
4 When multiple preventive maintenance techniques are applied at the same time and there is no experience to judge the advantages and disadvantages, a technical and economic comparison should be made.
5 Classification of preventive maintenance techniques
5.1 General provisions
5.1.1 Preventive maintenance techniques for asphalt pavements can be classified into different types such as sealing, overlay and in-situ thermal regeneration.
5.1.2 Material innovation, equipment innovation and process innovation of preventive maintenance techniques shall be actively carried out to continuously improve their technical performance, construction efficiency and economy and to reduce the impact of maintenance construction on traffic.
Article description
In recent years, preventive maintenance of asphalt pavements in China has continued to innovate and new technologies have emerged. For example, the fibre seal layer made by adding a layer of fibres and modified emulsified asphalt on top of the crushed stone seal layer, the composite seal layer made by the combination of crushed stone seal layer or fibre seal layer plus micro-surface area, crushed stone seal layer plus thin slurry seal layer; and then for example, the use of special construction equipment to sequentially sprinkle/spread the interlayer interface agent, emulsified high viscosity asphalt, aggregate, second emulsified high viscosity asphalt, surface protection agent and other materials into the original pavement in multiple layers simultaneously "Although the new technologies vary, they are generally based on the technologies specified in this specification. Material improvements, process improvements or combinations of different technologies on top of each other provide more technical options for preventive maintenance.
6 Design of preventive maintenance works
6.1 General provisions
6.1.1 The design of preventive maintenance works for asphalt pavements shall include investigation and testing and evaluation, technical design, material composition design, traffic organisation design, etc.
6.1.2 The design of preventive maintenance works shall conform to the relevant provisions of the current Specification for the Design of Asphalt Pavement Maintenance of Highways (JTG 5421), follow the principle of sectional design and classification treatment, and carry out the design as a design unit.
6.1.3 Detailed investigation and testing of the technical condition of the pavement shall be carried out as required, and the causes of pavement distress shall be accurately judged and analysed.
6.1.4 One-stage construction drawing design is appropriate for preventive maintenance works. Dynamic design should be implemented, and the design should be changed in time when the technical condition of the pavement, material condition, etc. change significantly compared with the design phase.
7 Grouting and jointing
7.1 General provisions
7.1.1 The performance of the sealant for grouting and the adhesive for sticking joints shall meet the requirements of the design and the relevant specifications.
7.1.2 The construction site should be cleaned up before grouting and jointing to ensure that the cracks and the surrounding area are dry and clean to avoid bonding failure.
There should be no loose, gnawed edges in the slotted construction.
7.1.3 Slotting and grouting is recommended for transverse cracks in pavements, and sticking is recommended for longitudinal cracks in pavements.
7.1.4 Grouting and jointing should be carried out in temperatures above 5 "C and not in rainy weather.
7.1.5 Where not provided for in this specification, the relevant provisions of the current Technical Specification for Maintenance of Asphalt Pavements on Highways (JTG5142) shall apply.
8 Fog seal layer
8.1 General provisions
8.1.1 The fog seal layer shall be selected from emulsified asphalt or reductant materials according to the original pavement condition.
Article Description:
Reducing agent materials are mainly composed of saturated aromatic hydrocarbons and can improve the performance of ageing asphalt. Emulsified asphalt fog seal materials consist of emulsified asphalt, modifiers, additives and fine aggregates; depending on the situation, the emulsified asphalt, modifiers and additives can be mixed together in advance to form an emulsified asphalt mixture.
9 Gravel seal and fibre seal
9.1 General provisions
9.1.1 The crushed stone seal shall be constructed at an ambient temperature above 10°C and shall be applied in a dry condition on the road surface.
Article Description
When the crushed stone seal binder is emulsified bitumen, the road surface may be wet but there must be no water.
9.1.2 According to different construction techniques, crushed stone seal can be divided into synchronous crushed stone seal and asynchronous crushed stone seal. According to the different particle sizes of the aggregates, the crushed stone seal can be divided into sand type, fine type and medium type, and the corresponding maximum particle sizes of the crushed stone are 5mm, 10mm and 15mm respectively.
9.1.3 Aggregate mud content and needle flake content shall be strictly controlled in gravel seal.
9.1.4 Material requirements, design, construction and construction quality control of fibre sealing layer shall conform to the relevant provisions of the current Technical Specification for Maintenance of Asphalt Pavements on Highways (JTG 5142).
10 Micro-surface and thin slurry sealing layer
10.1 General provisions
10.1.1 Micro-surfacing can be divided into MS-2, MS-3 and MS-4 types according to the grade of minerals, and into two grades A and B according to the performance. Grade A microsurfacing is recommended for tunnel road surfaces, night construction and sections with higher performance requirements.
Article Description
Compared with the Technical Specification for Maintenance of Asphalt Pavements on Highways (JTG 5142-2019) and the Technical Guideline for Microsurfacing and Diluted Slurry Seal, this article distinguishes between Class A and Class B microsurfacing, and also adds the MS-4 type of grading.
10.1.2 Diluted slurry seal can be divided into ES-1, ES-2 and ES-3 types according to the grade of mineral materials, and into fast open traffic type and slow open traffic type according to the speed of open traffic.
10.1.3 The temperature during the construction and maintenance period of the micro-surface and thin slurry seal shall be higher than 10C.
11 Thin overlays and ultra-thin overlays
11.1 General provisions
11.1.1 SMA-10/13, AC-10/13, OGFC hot mix or warm mix asphalt mixtures matching the thickness of the pavement may be used for thin overlays; the binder shall be high viscosity modified asphalt, polymer modified asphalt, rubber modified asphalt or road petroleum asphalt depending on the application.
Article description
In engineering practice, SMA and AC type mixes are used in thin layer overlays, while OGFC type mixes are used to achieve drainage and noise reduction effects. The Technical Specification for Maintenance of Asphalt Pavements (JTG 5142-2019) also gives a BPA-type mix for a skeleton-void type gradation with a void ratio of 10-15%, which is relatively little used in engineering practice.
11.1.2 ultra-thin overlay can be used to match the thickness of the pavement void type ultra-thin overlay UTO-5/10/13 type and dense ultra-thin overlay UTOD-5, SMA-5/10, AC-5/10 type of hot mix asphalt mixture or warm mix asphalt mixture, binder should be selected according to the use of high viscosity modified asphalt, polymer modified asphalt, rubber modified asphalt, Sticky layer should be used SBS modified emulsified asphalt, high viscosity modified emulsified asphalt or non-stick wheel modified emulsified asphalt.
12 Sealer coverings
12.1 General provisions
12.1.1 The construction environment and temperature requirements of the gravel seal, thin layer cover and ultra-thin cover shall conform to the requirements of sections 9.1 and 11.1 of this specification.
12.1.2 After the construction of the crushed stone seal is completed, timely rolling is desirable and excess crushed stone shall be recycled before overlaying or sealing.
13 Post preventive maintenance assessment
13.0.1 It is desirable to establish a post-preventive maintenance assessment mechanism for asphalt pavements, which may achieve all or some of the following objectives through post-assessment, as required:
1 Summarise the effectiveness of preventive maintenance techniques and develop a realistic list of pavement maintenance techniques;
2 To summarise the complete chain of evidence of pavement distress;
3 Modify pavement preventive maintenance decision making methods;
4 Establish a realistic decay model of pavement conditions to determine the expected life of preventive maintenance techniques;
5 Develop a practical guide to pavement preventive maintenance techniques.
Appendix A Maintenance Benefit Cost Analysis Methodology
Appendix B Initial Wear Loss Test for Mix Maintenance at Micro Surface
Contents of JTG/T 5142-01-2021
1 General
2 Terminology and symbols
3 Basic requirements
4 Preventive maintenance decision making
5 Classification of preventive maintenance techniques
6 Design of preventive maintenance works
7 Grouting and jointing
8 Fog seal layer
9 Gravel seal and fibre seal
10 Micro-surface and thin slurry sealing layer
11 Thin overlays and ultra-thin overlays
12 Sealer coverings
Appendix A Maintenance Benefit Cost Analysis Methodology
Appendix B Initial Wear Loss Test for Mix Maintenance at Micro Surface
