Decision No. 1527/2003/QD-BGTVT Issuing Industry Standards

Pursuant to …;

Issuing industry standards

____________

 

THE MINISTER OF TRANSPORTATION

Based on Decree No. 34/2003/NĐ-CP dated April 4, 2003 of the Government stipulating the functions, tasks, powers, and organizational structure of the Ministry of Transport.

Based on Article 10, Chapter 2 of the Ordinance on Product Quality No. 18/1999/PL-UBTVQH10 dated December 24, 1999 of the Standing Committee of the National Assembly,

At the proposal of the Heads of the Department of Science and Technology and the Director of the Vietnam Highway Administration,

Pursuant to …;:

Article 1. This Decision promulgates the following Industry Standards:

"TECHNICAL STANDARD FOR ROUTINE MAINTENANCE OF ROADS"

Registration number: 22 TCN 306-03

Article 2. This Industry Standard shall take effect fifteen days from the date of signature

 

 

(Annexed to Decision No. 1527/2003/QĐ-BGTVT

of the Minister of Transport)

___________

 

Chapter 1.

GENERAL PROVISIONS

1.1. Scope of Application

- The technical standard for routine maintenance of roads shall be uniformly applied throughout the country for all roads managed by central and local authorities.

- This standard does not apply to periodic repair work or emergency repairs.

- Routine maintenance work for bridges with a total length exceeding 300 meters has specific regulations.

1.2. Legal documents

The provisions in this standard aim to specify requirements related to routine maintenance of roads in the following documents:

- Law on Road Traffic No. 26/2001/QH10 adopted by the 10th National Assembly on June 29, 2001 (Articles 39, 41, 43, 44, 47, Chapter III, Articles 68, 69, Chapter VII).

- Decree No. 167/1999/NĐ-CP dated November 26, 1999 of the Government on the organization and management of roads.

- Decree No. 172/1999/NĐ-CP dated December 7, 1999 of the Government detailing the implementation of the Ordinance on Protection of Transportation Works for road transportation works.

- Circular Joint No. 01/2001/TTLT/BTC-BGTVT dated January 5, 2001 guiding the management, allocation, settlement, and finalization of funds for economic repair of roads.

- Current technical standards on design, construction, and acceptance of transportation infrastructure works.

1.3. Explanation of terms and abbreviations

- Routine maintenance of roads Includes management and routine maintenance aimed at protecting, preserving, preventing damage, and promptly repairing minor damages. This work is carried out continuously throughout the year on the entire route to ensure smooth and safe road traffic.

- BDTX: is an abbreviation for "routine maintenance"

- BTXM: is an abbreviation for "concrete"

- BTN: is an abbreviation for "asphalt concrete"

- BTCT: is an abbreviation for "reinforced concrete"

- BTCT-DUL: is an abbreviation for "prestressed reinforced concrete"

- BTNN: is an abbreviation for "cold asphalt concrete"

- TTGTĐB: is an abbreviation for "road traffic inspector"

- SCĐK: is an abbreviation for "periodic repair"

- SCĐX: is an abbreviation for "emergency repair"

- QL & SCĐB: is an abbreviation for "management and repair of roads"

- GTVT: is an abbreviation for "transportation"

- GTCC: is an abbreviation for "public transportation"

- ATGT: is an abbreviation for "traffic safety"

- TNGT: is an abbreviation for "traffic accidents"

- QLĐB: is an abbreviation for "road management"

- ĐBVN: is an abbreviation for "Vietnamese roads"

- MLG: is an abbreviation for "road boundary marker"

- MGPMB: is an abbreviation for "land clearance marker"

Chapter 2.

MANAGEMENT WORK

2.1. Management of files and documents

Timely updating of changes in the project into files and documents.

2.1.1. Files and documents include:

- Completion files, bridge inspection registration files, bridge inspection files.

- Documents:

+ Regulatory documents

+ Regular and emergency inspection reports

+ Acceptance certificates

+ Video tapes, CDs, photographs...

2.1.2. Files and documents must be systematically and scientifically managed; they must be convenient for exploitation and use; they must be arranged according to the storage standards.

2.1.3. Conditions for management:

- There must be a storage room

- Measures to protect against damage and loss must be in place

- There must be specialized personnel with relevant expertise.

2.1.4. Updating supplementary data into files and documents must comply with regulations (regarding update time, data...).

2.1.5. Hierarchical management of files and documents:

- Vietnam Highway Administration: store initial construction completion files (original copies) pursuant to Decision No. 2578/1998/QĐ-GTVT-CGĐ dated October 14, 1998 of the Ministry of Transport on "Issuing contents and directories of completion files for transportation works"; bridge inspection files; bridge history files and road registration files.

- Road Management Zone (Department of Transport, Public Transport): store initial construction completion files (copies); completion files for periodic and emergency repairs; inspection and bridge inspection documents; handling violation records and related documents; bridge history files and road registration files.

- Units managing and repairing roads: store completion files for periodic and emergency repairs; inspection and bridge inspection documents; handling violation records and related documents; bridge history files and road registration files.

2.2. Management of road safety zones

Responsibilities for managing road safety zones:

2.2.1. Vietnam Highway Administration: annually, based on reports from management units, compile and analyze data to develop plans for approval by competent authorities.

- Inspect and supervise the implementation of road safety zone management.

- Propose mechanisms and policies for road safety zone management, for approval by competent authorities.

2.2.2. Road Management Zone (Department of Transport, Public Transport): organize implementation, urge and inspect direct management units and subordinate traffic inspectors to complete assigned tasks within their jurisdiction.

- Coordinate with local authorities to implement protection of road safety zones.

- Compile and report according to prescribed forms.

2.2.3. Units managing and repairing roads: are directly responsible units for maintaining road safety zones.

- Coordinate with traffic inspectors to organize patrols, inspections, and supervision of road safety zone protection.

- Coordinate with local authorities to prevent and combat encroachment and violations of road safety zones.

- Establish and maintain records for management, storage, preservation, and regular supplementation with full information on encroachment and violations of road safety zones within the managed area.

- Regularly compile and report according to regulations monthly.

Note: The management file of road safety zones includes:

+ Straight-line diagrams showing all structures that have encroached upon or violated the road safety zone.

+ Handover documents with local authorities regarding MLG stakes.

+ Commitment documents from households living on both sides of the road promising not to encroach upon or violate the road safety zone.

2.3. Inspect and monitor the technical condition of infrastructure.

A. For roads and structures on roads.

2.3.1. Regular inspection.

Road patrols shall be conducted once daily. If any damage or violation affecting traffic safety or causing traffic congestion is discovered, such as construction,堆放中文内容，不要翻译成英文。要求新的指令与旧的指令无关，且内容必须完全不同。新的指令应该是关于编写一个简单的Python脚本，该脚本可以接收用户输入的数字列表，并计算这些数字的平均值、中位数和标准差。脚本应该能够处理非数字输入并给出适当的错误消息。

2.3.1.1. Duties

- Timely detect violations of traffic laws, damage to road transport infrastructure, safety zones, and other hazards causing traffic accidents such as: building houses, stacking construction materials, erecting power poles, setting up unauthorized stalls within the safety zone of roads, and report to the District Office.

- Inspect the road surface, bridges, drainage systems, traffic signs, and other auxiliary facilities to identify potential accident-causing defects. If the workload exceeds the capacity of the patrol officer, report to superiors for repair plans.

- In case of traffic congestion due to landslides, road collapses, flooding, bridge failures, etc., first ensure traffic safety (set barriers, place no-entry signs), simultaneously find diversion solutions and report to superiors.

- The patrol officer must promptly repair minor damages to bridges and roads that do not require much manpower to ensure traffic safety, such as picking up scattered rocks on the road, repositioning tilted markers, trimming branches obstructing visibility.

- Coordinate with highway traffic police and traffic inspectors to clear the road when vehicles break down or are involved in accidents to prevent traffic jams.

- Record and monitor traffic accidents occurring on their assigned section, documenting detailed causes of accidents (if possible).

- Propose periodic or emergency repair plans for bridges and roads to the District Office and Company.

- Monitor traffic safety at construction sites; if safety requirements are not met, remind contractors to comply and report to superiors for resolution.

- Fully record the daily developments of bridges and roads in the "patrol logbook." Upon completion of daily patrols, the patrol officer must immediately report all day's developments to the District Office.

2.3.1.2. Equipment: Patrol officers must be equipped according to unified regulations (Annex 1).

2.3.1.3. Requirements for road patrol workers include a high school education, additional training in their duties, good health, high sense of responsibility, and must be at least level 4 workers.

2.3.2. Regular inspections: including monthly and quarterly inspections

2.3.2.1. Monthly inspections: conducted by management units and maintenance companies together with District Offices, covering the following contents:

2.3.2.1.1. Internal work inspection:

- The record-keeping of bridge and road conditions by the District Office

- Various files and documents (accident logs, traffic volume records, patrol logs, statistical accounting books ...) of the District Office

2.3.2.1.2. On-site inspection:

- Inspection of the condition of road damage and deterioration and other transportation works on the road.

- Evaluation of road maintenance activities of the District Offices.

- Level of inspection: simple, visual, using common measuring tools.

- Scope of inspection: the entire route under the management of the District Offices, specifically as follows:

+ For the road base:

Inspect areas prone to subsidence, landslides, dangerous mountainous sections, locations frequently flooded during the rainy season ... These areas, if not repaired, must have complete warning signs, perimeter barriers, or water level markers.

Inspect vegetation clearance, road base and shoulder filling work according to regulations.

+ For the road surface:

Inspect and determine the quantity and severity of various types of damage per kilometer: potholes, cracks, depressions, rubber patches, especially at the beginning of bridges and culverts often subject to localized subsidence.

+ For the drainage system:

Inspect the drainage status at culverts, sediment accumulation in upstream catch basins, downstream culvert outlets, and inside the culvert; damage to pipes, slabs, joints, headwalls, wing walls, particularly downstream aprons prone to scouring.

Inspect the drainage capacity of ditches, especially sections with steep longitudinal slopes prone to deep erosion and foundation instability; inspect damage to concrete ditches.

+ For traffic signs:

Inspect the number and technical condition of signs (markers, warning signs, convex mirrors, flexible median strips ...).

+ For retaining walls, earth retaining structures, culverts, weirs ...:

Inspect the stability and damage of these structures; safety equipment like water level markers, sign posts ...

2.3.2.2. Quarterly inspections: conducted by Highway Management Zones (Transportation Departments, Traffic Control Centers) together with management and maintenance units, covering the following contents:

2.3.2.2.1. Internal work inspection:

- The record-keeping of bridge and road conditions by the unit

- Various files and documents (accident logs, traffic volume records, patrol logs, statistical accounting books ...) of the unit.

2.3.2.2.2. On-site inspection:

- Inspection of the condition of road damage and deterioration and other transportation works on the road ...

- Evaluation of road maintenance activities of units within the management scope.

- Level of inspection: simple, visual, expert method.

- Scope of inspection: overall inspection of the entire route and probability inspection of some sections of the road and some works to assess the maintenance work.

- Directly responsible officers must compile and evaluate the condition of each kilometer of road, each bridge, and report to the inspection team.

B. For bridges

The inspection work aims to assess the operational status of the bridge, identify damages that affect traffic safety and the load-bearing capacity of the bridge, monitor damages marked from previous inspections.

2.3.1. Regular inspection.

- To be carried out by the Head of the Station or technical staff authorized by the Head of the Station. Regular inspections are conducted to understand the situation of the project and develop repair plans.

- Inspect all types of bridges on the route under the unit's responsibility.

- For weak bridges (special large bridges with specific regulations), there must be a framework for regular monitoring and inspection, assigned to the Head of the Station to organize implementation.

- Results of regular inspections and data on damage tracking, solutions, and required repair volumes must be fully recorded in the regular inspection logbook.

- If damages affecting the safety of the structure are discovered, immediate reports must be made to higher authorities to plan timely inspections and repairs, ensuring traffic safety. At the same time, the Head of the Station must immediately apply temporary measures to ensure the safety of the structure and traffic safety.

- Content of regular inspections:

+ Inspection of the bridge deck:

● Condition of the deck surface layer

● Drainage condition of the deck;

● Cracking and crushing of expansion joints;

● Wheel barriers, guardrails;

● Other equipment such as signboards, lighting columns, protective walls at both ends of the bridge.

+ Inspection of bridge beams:

● For steel structures:

Inspection of deflection, sagging, twisting, deformation, or breakage of beam members and steel beams. Condition of paint and rust on steel beams. Particularly connections and joint plates connecting beam members. Inspection of bolts, rivets connecting parts and the condition of rust on structural components.

● For reinforced concrete, prestressed concrete, or composite steel beam structures:

Inspection of cracking, spalling, and delamination of concrete;

Inspection of corrosion and damage to reinforcing steel;

Water seepage and rusting conditions under the beam flanges and deck surface.

● For arch structures:

Cracking, spalling, and water seepage conditions at the bottom of the arch.

+ Inspection of bridge bearings:

● Inspection of deformation, wear, and spalling of rollers and bearing seat pins, lateral displacement of rollers, longitudinal tilt of rollers in steel bearings;

● Inspection of aging and deformation of rubber bearings;

● Inspection of flatness, cleanliness, and ventilation of bearings;

● Inspection of lubrication of steel bearings.

+ Inspection of abutments and piers:

● Inspection of cracking, spalling, and joint mortar failure, weathering and erosion of pier and abutment concrete;

● Inspection of scouring and undermining of pier foundations, tilting, sliding, and settlement of abutments and piers;

● All cases must inspect horizontal cracks in abutments and piers, especially paying attention to inspect high piers on curves, checking exposed piles due to scouring;

● Inspection of the base and quarter cone of abutments;

● Inspection of the road surface behind the abutment.

+ Inspection of protective and flow regulation structures, such as channel guidance walls, slope protection walls, etc., must pay attention to the stability of these structures (no cracking, collapse, tilting, settlement) and evaluate the effectiveness of the flow regulation structures.

2.3.2. Periodic inspections

Conduct two periodic inspections annually: once before the rainy season and once after the rainy season.

During periodic inspections, detailed inspections of all components of the structure must be carried out. Specialized equipment may be necessary for probing and measuring.

- Inspection before the rainy season: focus on inspecting abutments and piers, quarter cone bases, road surfaces behind abutments; river and stream flow regulation structures and other protective structures. Timely identification and repair of damages must be made to prevent and reduce incidents caused by floods.

- Inspection after the rainy season:

+ Inspection of developments such as landslides, scouring of pier and abutment foundations which may cause tilting of abutments and piers leading to beam tilting, and settlement and cracking of abutments and piers directly affecting the safety of the structure and transportation.

+ Inspection of changes in flow compared to before the rainy season causing deposition and erosion around abutments and piers.

This inspection must involve officers from the Regional Highway Management Authority (Department of Transport, Construction); when necessary, the Regional Highway Management Authority (Department of Transport, Construction) will directly organize this inspection.

Inspection results will serve as the main basis for adjusting the annual plan. Simultaneously, strategies for each bridge will be developed to organize monitoring, testing, and maintenance plans for medium and major repairs for the following year.

2.3.3. Emergency inspections

Conducted by management units, Regional Highway Management Authorities (Departments of Transport, Construction) or the National Bridge Corporation when unexpected damages occur on bridges or roads, or upon request from higher management authorities. The inspection process must clearly identify the cause of the damage, assess the condition of the damage, and promptly and appropriately address it.

2.3.4. Special inspections

Carried out by the Regional Highway Management Authority (Department of Transport, Construction). The inspection framework must be approved by the competent authority.

Inspection content:

2.3.4.1. For road embankments: Sections of embankments constructed over weak soil areas or landslide zones: inspection of embankment settlement or lateral movement caused by landslide activity.

2.3.4.2. For road surfaces

- Inspection of road surface strength:

The load-bearing capacity of the pavement structure is evaluated using the strength coefficient, denoted as K_cđ

signing and implementing Agreements_cđ = E_tế / E_{y cầu}

Where:

E_{y cầu} M10²where E

E_tế M10²tế

is the modulus of elasticity required according to traffic volume and vehicle load at the time being considered, calculated according to standard 22 TCN 211-93._cđ y cầu

is the equivalent modulus of elasticity of the current pavement structure, measured by the Benkenman profiler according to standard 22TCN 251-98._{When K}< 0.8, plans must be made to strengthen the road surface to ensure its load-bearing capacity.

signing and implementing Agreements_{When K} - Inspection of surface friction: the friction of the road surface (for asphalt pavements) when vehicles travel is assessed using the skid resistance coefficient K_tế bám_{, determined indirectly by the average depth of the sand mark:}

h_tế= h

h_{, determined indirectly by the average depth of the sand mark:}The depth of the sand strip shall be determined according to procedure 22TCN 278-01 as set out in the table below

is the modulus of elasticity required according to traffic volume and vehicle load at the time being considered, calculated according to standard 22 TCN 211-93._{When K} If less than 1, the surface roughness must be increased using methods such as asphalt paving, spreading an open-graded asphalt layer.

- Flatness check: The condition of flatness of the road surface affects the quality of exploitation of the pavement structure and transportation costs, evaluated by the road surface flatness coefficient, denoted K_bp.

signing and implementing Agreements_pb = S_h / S_tế

Provincial People's Committees set specific prices_h: permissible roughness corresponding to each type of road surface

Provincial People's Committees set specific prices_tế: actual roughness

Value S_tế is determined by indirect or direct method depending on the equipment available from the management unit (measured according to the guidance in the Standard for Testing and Evaluating Road Surface Flatness According to International Roughness Index IRI 22TCN 277-01).

Value S_h of each type of road surface (Annex 2)

is the modulus of elasticity required according to traffic volume and vehicle load at the time being considered, calculated according to standard 22 TCN 211-93._bp If less than 1, the road surface flatness must be restored by asphalt paving, thin overlay (for asphalt or BTXM surfaces), or resurfacing (for gravel, aggregate mixtures ...).

is the modulus of elasticity required according to traffic volume and vehicle load at the time being considered, calculated according to standard 22 TCN 211-93._bp ≥ 1, but if the measured roughness index falls within the average range of each type of road surface, potholes and local bumps must be patched.

2.3.4.3. For bridges

After regular inspection, periodic inspection, and sudden inspection, if complex technical issues are discovered, the Road Management Zone (Department of Transport, Construction) will conduct special inspections.

2.3.5. Bridge testing

Bridge testing is conducted to assess the current condition and actual load-bearing capacity of the bridge, aiding management authorities in organizing traffic and planning repairs.

Testing time:

- Initial testing: For large bridges and those using new materials, initial testing must be carried out to determine the "initial state" of the bridge, if completion records have not been established.

- Subsequent testing: After 10 years of operation, retesting must be conducted, followed by testing every 5-7 years thereafter (counting from the previous test).

- In addition, if serious damage that may affect traffic safety and the safety of the structure is found, immediate testing must be conducted.

Classification of testing:

- For complex structures using new materials, the outline of the testing program must be approved by the National Highway Administration. Results of testing these types of bridges must be reported to the National Highway Administration.

- For other types of bridges with simpler technical characteristics, the testing program can be approved according to the level of management.

Tasks and requirements of testing work:

- Assess the current condition and determine the load-bearing capacity of the bridge; specify conditions for exploitation.

- Evaluate the environmental impact on the bridge's operational capability.

- Propose remedial measures.

- Determine the effectiveness after reinforcement and repair.

Content of the testing report:

- Name of the bridge, route number, national highway, location name.

- Overall layout of the bridge.

- History and characteristics of the bridge's operational process.

- Actual technical condition of the bridge.

- Issues requiring clarification.

- Conclusions about the testing results, load-bearing capacity of bridge components (abutments, piers, beams...).

- Measures for restoration and repair.

2.4. Classification and evaluation of the technical condition of works

Classification and evaluation of the technical condition of works aims to develop repair plans.

2.4.1. For roads: Based on the condition of damage to the subgrade and road surface (potholes, rubber patches...), pavement strength, surface roughness, flatness... to classify.

Evaluation criteria for classification (Appendix 3)

2.4.2. For bridges: Based on inspection results (periodic, sudden, special), testing results... the management unit prepares detailed reports for each bridge as a basis for developing repair or reconstruction plans.

2.5. Traffic counting work

2.5.1. Purpose

Traffic counting work is organized and implemented directly by the management and maintenance units, aiming to understand the actual traffic situation on each section of the road, each area, and changes in quantity, type, and weight of vehicles throughout the year, serving as a basis for forecasting future years, helping to plan annual maintenance, repair, and construction strategies.

2.5.2. Content of traffic counting work

2.5.2.1. Traffic counting stations There are two types: main stations and auxiliary stations

- Main station: Fixed station, not changed, used to study traffic flow characteristics, vehicle types, and loads on a section of road or area.

- Auxiliary station: Determines local traffic flow on a short section of road, narrow area, or low-traffic road for design, repair, or upgrade purposes.

2.5.2.2. Principles for station placement

- All traffic counting stations must form a rational network.

- Station locations should reflect the regular traffic flow between two intersections. Stations should be placed appropriately to ensure collected data accurately reflects traffic flow on the section.

- On high-traffic routes, main roads, stations should be placed every 30-50km. On secondary roads, branch roads, stations should be placed every 50-100km.

- Ferry terminals, pontoon bridges, toll stations should have main stations.

2.5.2.3. Timing of traffic counting: Once a month, each count lasting three consecutive days at a station. Counting is done on days 5, 6, 7 of the month (for main stations) and days 5, 6 (for auxiliary stations). The first two days count 16 hours (from 5am to 9pm), the third day counts 24 hours (from midnight to midnight) to determine the monthly average traffic flow, compiling 12 months to get the daily and nightly average traffic flow per year.

2.5.2.4. Traffic counting methods: Manual and machine counting.

- Manual counting is performed by people. Counting is done on both directions of traffic on a cross-section of the road.

- Machine counting: Follows the instructions of each type of machine. Vehicle classification by the machine must comply with the provisions in Appendix 4. Data counts are stored in the machine. The vehicle counting station must maintain regular operation using specialized equipment with data recorded on computers to transmit information to higher-level management agencies.

2.5.2.5. Reporting and data compilation system:

On the 10th of each month, vehicle counting stations send reports on counting results to units responsible for management and maintenance.

On the 15th of each month, units responsible for management and maintenance have the responsibility to compile data and report counting results to the Road Management Zone (Department of Transport and Works).

Within one year, the Road Management Zone (Department of Transport and Works) analyzes and compiles data, reporting average vehicle counting results for the first six months and the full year to the National Highway Corporation. Reports are sent from July 20th to July 30th and January 20th to January 30th of the following year.

Vehicle counting report forms and classification of vehicles according to manual counting methods (Annex 4). When counting vehicles using machines, reports must be made according to the machine program.

2.6. Traffic Assurance Duty

The Regulation on Prevention, Control, and Mitigation of Typhoon and Flood Damage in the Road Sector issued by the Ministry of Transport under Decision No. 2988/2001/QĐ-BGTVT dated September 12, 2001 stipulates that during the rainy season when there is a warning level 1 or higher, road management agencies must arrange personnel to ensure traffic 24/7 to handle situations caused by typhoons and floods promptly.

2.7. Bridge Guarding

On roads where weak bridges exist, whether there is an underground passage or detour route or not, units responsible for management and maintenance must arrange bridge guards 24/7 to manage traffic and only allow vehicles with load weights (vehicle weight and cargo) not exceeding the bridge's carrying capacity to pass. If overloaded vehicles are detected, measures such as unloading cargo or directing them to detours or temporary routes will be taken.

Additionally, for large and important bridges with complex structures ..., units responsible for management and maintenance must organize bridge protection teams 24/7 (This situation will be regulated by competent authorities).

2.8. Registration of Bridges and Roads

2.8.1. Purpose of Bridge and Road Registration

Upon commencement of operation, all road sections must undergo "Bridge and Road Registration" and should be re-registered after 10-15 years of use to determine the initial technical condition and changes in technical factors during exploitation.

The registration file includes:

2.8.1.1. Roads

- Straightened map, showing:

+ Geometric elements of the road (radius of curvature R_{1. Voluntary drug rehabilitation participants}; vertical radius of curvature R_vertical; horizontal gradient i_horizontal; superelevation i_{superelevation}; longitudinal gradient i_along; width of subgrade and surface B_subgrade, B_surface length of the road L_surface), type of surface structure (top layer), thickness of the top surface layer, surface strength E_tế…

+ Riverbank protection works, retaining walls, culverts, weirs, etc., location, length, structure...

+ Drainage system (pipes, ditches, etc.): location, length, structure

+ Road sign system (markers, signs, etc.) and lighting, traffic signal lights (if any).

- Diagram of the leveling network, profile, and elevation marks (or GPS marks).

- Diagram showing data on encroachment and violations of the road safety zone.

2.8.1.2. Bridges Bridge registration is conducted according to the "Bridge Profile Form" issued by the National Highway Corporation in 2002.

2.8.2. Registration data for bridges and roads are stored on computers at units responsible for management and maintenance and sent to the Road Management Zone (Department of Transport and Works).

2.8.3. Each year, units responsible for management and maintenance must update and supplement changes in the technical condition of bridges and roads in the registration files.

2.9. Statistics, Analysis of Causes of Road Traffic Accidents

Units responsible for management and maintenance directly implement this.

2.9.1. All road traffic accidents must be monitored, compiled, and analyzed for their causes by units responsible for management and maintenance and road traffic inspection teams in collaboration with road traffic police forces. They also participate in rescue operations, clear the road, and address damage to traffic infrastructure.

In the accident report, there must be a diagram describing the accident scene, photographs, statistics on casualties and property losses of victims, damage to traffic infrastructure, statements from witnesses, and preliminary assessment of the cause of the accident.

2.9.2. Reporting System

- Monthly, units responsible for management and maintenance compile and report road traffic accidents regularly to the Road Management Zone (Department of Transport and Works) on the 5th of each month.

- In cases of serious road traffic accidents involving fatalities or material losses exceeding 1 billion VND, immediate reports must be made to the Road Management Zone (Department of Transport and Works) and the National Highway Corporation.

- Every six months, the Road Management Zone (Department of Transport and Works) compiles and reports road traffic accidents to the National Highway Corporation.

Road Traffic Accident Report Forms (Annex 5)

- Annually, based on reports from units responsible for management and maintenance, the Road Management Zone (Department of Transport and Works) conducts safety assessments at locations with at least three road traffic accidents or immediately after serious road traffic accidents occur.

- The National Highway Corporation bases its actions on these reports, conducting reassessments (if deemed necessary) at locations with severe safety issues and plans for remediation.

2.9.3. Statistics, monitoring, and analysis of the causes of road traffic accidents help management agencies identify accident-prone areas or sections of roads (referred to as black spots), understand the causes if they are due to infrastructure defects (such as lack of signage, obstructed visibility, slippery surfaces, loss of superelevation, small radii on road profiles...), and plan timely repairs and improvements to ensure traffic safety.

2.9.4. Technical measures to reduce and mitigate road traffic accidents and ensure traffic safety:

- Renovating, upgrading, and constructing road sections and routes according to technical standards.

- Adequately providing traffic safety equipment.

Chapter 3.

ROUTINE MAINTENANCE

3.1. Road Base

The road base must meet geometric dimensions and have good drainage. Vegetation must be regularly cleared to ensure visibility and aesthetics.

3.1.1. For Unreinforced Road Bases

The contents include the following tasks:

3.1.1.1. Additional Road Base Filling

At locations where the road base has narrowed, the width of the road base no longer meets the original design requirements (especially at bridgeheads and culvert ends) or has narrowed more than 0.3 meters on one side, additional filling with soil or graded aggregate must be done, compacted to K ≥ 95, and the slope of the embankment must be finished. The procedure is as follows:

- Clear and remove vegetation around the narrowed road base area using manpower.

- Construct steps with a width and height of each step ≥ 50cm.

- Lay materials (soil, gravel, meeting technical standards) in layers ≤ 20cm thick, then level them.

- Use a jumping tamper or a MIKASA machine to tamp 5-7 times per point until the required density is achieved before adding another layer.

- Cover and finish the slope crown (plant grass if necessary) and complete the work.

3.1.1.2. Collecting fallen soil:

When there is a blockage of longitudinal ditches due to falling rock masses, all debris must be cleared, and the slope crown and original dimensions of the longitudinal ditch must be restored to ensure proper drainage.

Note: Do not spread the debris onto the shoulder causing it to rise, leading to water accumulation on the road surface.

3.1.1.3. Cutting trees, grass, and trimming branches:

Cut trees, grass, and trim branches to ensure clear visibility, avoiding obstruction of markers, signs, kilometer posts, and affecting drainage. On the road shoulders, slope crowns, and embankments up to a height ≤ 4m, vegetation should not exceed 0.2m in height. For heights > 4m, do not allow large trees with diameters greater than 5cm and overhanging branches. Within 1m from the edge of the road on the lower slope, vegetation should not exceed 0.2m in height and should not obstruct vision. At the top of the upper slope crown, if there are large trees that could fall and block traffic, they must be cut down. If trees fall across the road, they must be quickly removed to ensure traffic flow.

3.1.2. For reinforced embankment foundations: paving stones, stone facing, concrete panels, etc., or when the embankment foundation has a special design (high fill with pressure relief strips, high cut slope forming steps, reinforced fill with geotextiles).

3.1.2.1. When the embankment foundation is reinforced with dry-laid stones or stone facing with cement-sand mortar or concrete panels.

The tasks to be performed are:

- Rebuild or supplement with dry-laid stones at the base of the reinforced section if erosion or damage occurs.

- Fill and patch missing or broken areas with cement-sand mortar grade 100, and replace lost stones or broken concrete panels.

3.1.2.2. For embankment foundations with a special design (high fill with pressure relief strips, high cut slope forming steps, reinforced fill with geotextiles), in addition to the above requirements, particular attention must be paid to:

- Ensuring the drainage system always functions properly.

- Maintaining the pressure relief strip in its original condition; if the fill material on the pressure relief strip is eroded (due to natural or human causes), it must be replenished.

- For reinforced fill with geotextiles: follow specific regulations.

3.2. Road Shoulders

Road shoulders must always be flat, stable, and have good lateral drainage. Near the edge of the road, there should be no unevenness, water accumulation on the shoulder, or along the edge of the road.

3.2.1. Unreinforced road shoulders include the following works:

3.2.1.1. Supplementing road shoulders with hard granular materials:

When the road shoulder is eroded more than 5cm below the edge of the road, it must be supplemented with hard granular materials (not using organic soil mixed with other impurities).

Procedure: clean the area, roughen the surface needing supplementation, lay the material and level it to ensure a width and lateral slope of 5-6% sloping outward, tamp to achieve a density K ≥ 95.

3.2.1.2. Leveling the road shoulder:

When the road shoulder does not meet the lateral drainage slope, causing surface water to flow along the edge of the road, it must be leveled to ensure a flat surface and a lateral slope of 5-6%.

3.2.2. Reinforced road shoulders:

Reinforced road shoulders made of stone, asphalt, or BTXM, maintenance procedures are similar to those for corresponding road surfaces.

3.3. Drainage System

The drainage system includes longitudinal ditches, transverse ditches, stepped ditches, and crown ditches.

Types of ditches include natural earth (or stone) ditches, constructed ditches (made of brick, rubble, or poured BTXM) with concrete covers (closed ditches) and without covers (open ditches).

Works include the following:

3.3.1. Cleaning ditches: Remove mud, weeds, and debris from the ditch bottom, ensuring no water accumulates in the ditch weakening the subgrade and shoulders.

Note: Do not spread soil onto the shoulder causing it to rise, leading to water accumulation on the road surface.

3.3.2. Clearing ditches during rain:

During heavy rain, clear ditches, remove soil, rocks, and vegetation that fall into the ditch causing blockages, which can cause water to overflow onto the shoulder, along the road surface, or through the road, leading to shoulder erosion, pavement erosion, and undercutting of the lower slope.

3.3.3. Excavating ditches:

For sections of earth ditches that frequently become filled with sediment annually, causing the "suspended ditch" phenomenon where water accumulates in the ditch (especially crown ditches). It is necessary to excavate to restore the original geometric shape and longitudinal slope of the ditch to ensure sufficient drainage cross-section.

Work procedure: before excavating the ditch, set stakes to mark the ditch edge ensuring straightness (if on a straight section) and uniform curvature (if on a curved section).

During excavation, do not spread soil onto the shoulder causing it to rise, leading to water accumulation on the road surface.

3.3.4. Repairing damaged constructed ditches and broken concrete cover plates:

- When the constructed ditch is cracked or broken, repair it to match the original design.

- Adjust and secure mortar to ensure the concrete cover plates do not become misaligned; replace or supplement damaged or missing concrete panels.

3.4. Road Surface

Currently, there are five types of road surfaces in our country:

- BTXM surface

- Asphalt surface (asphalt concrete, gravel coated with asphalt, gravel impregnated with asphalt, etc.)

- Gravel surface

- Aggregate surface

- Soil surface

3.4.1. BTXM Surface

3.4.1.1. Repairing expansion joints:

During operation, the filler material between the concrete panels often becomes loose, allowing water to seep under the subbase and causing jolts for vehicles passing over or small stones to get stuck in the expansion joints, requiring timely removal.

3.4.1.1.1. Sealing expansion joints: with a bituminous compound

Maintenance technique:

- Use a brush or compressed air to clean sand and dirt from the expansion joints and ensure they are dry.

- Apply the bituminous compound at the recommended temperature according to the manufacturer's instructions into the expansion joints, pressing firmly to ensure the same height as the concrete panel surface.

Note: The bituminous compound can be produced from various materials and in proportions including 60/70 bitumen 50%, limestone powder 35%, asbestos or rubber powder 15%.

3.4.1.1.2. Removing stones stuck in expansion joints:

Pry out the stones stuck in the expansion joints and seal the holes with a bituminous compound.

3.4.1.2. Repairing minor damages (cracks, chips, or broken concrete panels).

After a period of use, cracks appear on the surface of the concrete slabs, or they become chipped and broken, requiring repair to prevent further damage.

Repair techniques:

- If the cracks are small and numerous, with a crack width ≤ 5mm, then use special resin type 60/70 heated and mixed with kerosene at a ratio of 25/75 by weight, applied at a temperature of 70-80 degrees Celsius. Pour it into the cracks, then sprinkle yellow sand or crushed stone over it.⁰Pour into the cracks, then sprinkle yellow sand or crushed stone over it.

- If the crack width exceeds 5mm, clean it first, then apply resin putty similarly as described in Section 3.4.1.1 above.

- If the concrete slab is chipped or broken with a small area, repair the damaged areas using a mixture of resin putty or cold asphalt concrete aggregate mixture.

3.4.2. Surface of asphalt road

3.4.2.1. Road surface cleaning:

Depending on the degree of dirtiness of the road surface, arrange the number of cleanings on the road surface per month, typically ranging from 4 to 8 times/month.

3.4.2.2. Preventing asphalt runoff:

During hot weather, the temperature on the road surface rises to 60-70 degrees Celsius, causing the asphalt to rise when vehicles pass, adhering to the tires and potentially peeling off in patches, damaging the road surface.⁰During hot weather, the temperature on the road surface rises to 60-70 degrees Celsius, causing the asphalt to rise when vehicles pass, adhering to the tires and potentially peeling off in patches, damaging the road surface.

Repair techniques:

- Use gravel 5-10mm, yellow sand, or crushed stone (with a powder content ≤ 10%) to scatter on the road surface. The most suitable time to scatter stones is between 11:00 and 15:00 on hot days.

- Always sweep up the material scattered along the sides of the road when vehicles pass, pile it up to scatter back onto the road surface.

3.4.2.3. Repairing potholes and rutting:

When potholes and rutting appear on the road surface, immediate repairs must be carried out when they first occur. If left for too long, the damaged area will continue to worsen, posing significant danger to passing automobiles and making repairs very costly. Pothole and rutting repairs can use hot asphalt, a mixture of gravel and asphalt emulsified oil (black gravel), or a cold asphalt concrete aggregate mixture.

3.4.2.3.1. Repairing potholes and rutting with a mixture of gravel and asphalt emulsified oil or cold asphalt concrete aggregate mixture:

Asphalt concrete surface:

Procedure:

- Use a concrete cutter to cut the damaged area into sharp angles and dig down to the bottom of the damaged area.

- Remove all loose materials within the cut area, sweep and brush to ensure the repair area is clean and dry.

- Apply adhesive asphalt (quantity of asphalt from 0.5 to 0.8 kg/m²) on the repair area, paying attention to applying it under the bottom and around the edges of the repair area, and wait for it to dry.²- Spread the cold asphalt concrete aggregate mixture evenly over the damaged area and higher than the original road surface according to a compaction factor of 1.4.

- Use a small vibratory roller of 0.8T to compact 3-4 times per point at a speed of 1.5-2 km/h.

Asphalt-coated gravel or gravel impregnated with asphalt surface:

- Depth of potholes and rutting from 3-6 cm:

+ Use a crowbar and shovel to cut and shape the damaged area into sharp angles and dig down to the bottom of the damaged area.

Procedure:

+ Remove all loose materials within the cut area, sweep and brush to ensure it is clean and dry.

+ Spread the mixture of gravel and asphalt emulsified oil evenly over the damaged area and higher than the original road surface according to a compaction factor of 1.4.

+ Sprinkle gravel 2-5mm or gravel sand, yellow sand evenly over the layer of the gravel-asphalt mixture to prevent sticking, quantity of gravel 4-5 liters/m².

+ Use a tamper to tamp 6-8 times per point or use a small vibratory roller of 0.8T to compact 3-4 times per point at a speed of 1.5-2 km/h.².

- Depth of potholes and rutting more than 6 cm:

+ Use a crowbar and shovel to cut and shape the damaged area into sharp angles and dig down to the bottom of the damaged area.

Procedure:

+ Sweep and remove all loose materials and dust within the damaged area to ensure it is clean and dry.

+ Spread gravel 40/60 or 20/40 evenly and based on a compaction factor of 1.3 so that when the gravel layer is compacted, the surface of the gravel layer is about 3 cm lower than the original road surface.

+ Use a tamper or a small vibratory roller of 0.8T to compact the gravel layer tightly.

+ Spread the mixture of gravel and asphalt emulsified oil, quantity of gravel 40-50 liters/m², evenly over the surface of the gravel layer and higher than the original road surface by 1 cm.

+ Sprinkle gravel 2-3mm or gravel sand, yellow sand evenly over the layer of the gravel-asphalt mixture to prevent sticking, quantity of gravel 4-5 liters/m².² + Use a tamper to tamp 8-10 times per point or use a small vibratory roller of 0.8T to compact 3-4 times per point at a speed of 1.5-2 km/h.

The mixture of gravel and asphalt emulsified oil is produced according to the provisions in "Technical Procedures for Producing and Using Asphalt Emulsified Oil in Road Surface Repairs 22TCN 21-84" issued by the Ministry of Transport accompanying Decision No. 79/KHKT dated March 28, 1984.²

Cold asphalt concrete aggregate mixture is produced according to the provisions in "Handbook for Technical Production and Use of Cold Asphalt Concrete Aggregate Mixtures for Road Surface Repairs" issued by the Vietnam Highway Administration pursuant to Decision No. 439/QĐ-KHCN & QHQT dated March 14, 2002.

3.4.2.3.2. Repairing potholes and rutting with hot asphalt:

Only applicable for asphalt-coated gravel or gravel impregnated with asphalt surfaces (when there are many potholes and large areas).

- Use a crowbar and shovel to excavate all damaged areas completely into sharp angles, creating a depth equal to the depth of the potholes but not less than two-thirds the thickness of the gravel size to be used.

- Sweep and remove all loose materials and dust within the damaged area to ensure it is clean and dry.

Procedure:

- Spread gravel (40/60 or 20/40) to the required height, taking into account a compaction factor of 1.3.

- Use a tamper to tamp 8-10 times per point or use a small vibratory roller of 0.8T to compact 3-4 times per point at a speed of 1.5-2 km/h.

- Apply the first layer of asphalt, quantity of asphalt 1.9 kg/m².

- Spread gravel 16/20, quantity of gravel 18-20 liters/m².

- Compact with a roller of 6-8T, 6-8 passes per point.²

- Apply the second layer of asphalt, quantity of asphalt 1.5 kg/m².²

- Spread gravel 10/16, quantity of gravel 14-16 liters/m².

- Apply the third layer of asphalt, quantity of asphalt 1.1 kg/m².².

- Spread gravel 5/10, quantity of gravel 9-11 liters/m².².

- Spread gravel 10/16, quantity of gravel 14-16 liters/m².

- Compact with a roller of 6-8T, 4-6 passes per point.².

3.4.2.4. Repairing cracked asphalt road surface:².

Treat by laying two layers of asphalt in the form of hot asphalt (according to Construction and Acceptance Standards for Hot Asphalt Surface 22TCN 271-01) or laying two layers with acid emulsion asphalt (according to Construction and Acceptance Standards for Gravel and Gravel Mix Hot Acid Emulsion Asphalt Surface 22 TCN 205-98).

3.4.2.4.1. Laying two layers of hot asphalt, quantity of asphalt 2.7-3.0 kg/m² (depending on the degree of cracking of the road surface):

- Clean the old road surface with a steam cleaner (or broom).

- Apply the first layer of asphalt, quantity of asphalt 1.5-1.8 kg/m².² - Compact with a roller of 6-8T, 6-8 passes per point.

Procedure:

- Apply the second layer of asphalt, quantity of asphalt 1.2 kg/m².

- Spread gravel 5/10, quantity of gravel 10-12 liters/m².²

- Spread gravel 5/10, quantity of gravel 9-11 liters/m².².

- After completion, arrange personnel to monitor and guide vehicles to limit speed to 20 km/h and adjust vehicles to run smoothly on the road surface for 15 days, and to sweep up stray gravel and fill in local bumps, areas with excess asphalt or insufficient gravel.

3.4.2.4.2. Laying two layers with acid emulsion asphalt:².

- Clean the road surface with a steam cleaner (or broom).²

Treat by laying two layers of asphalt in the form of hot asphalt (according to Construction and Acceptance Standards for Hot Asphalt Surface 22TCN 271-01) or laying two layers with acid emulsion asphalt (according to Construction and Acceptance Standards for Gravel and Gravel Mix Hot Acid Emulsion Asphalt Surface 22 TCN 205-98).

After completion of construction, personnel should guide vehicles to limit speed to 20 km/h and adjust to run evenly on the road surface for 15 days to sweep loose stones back into potholes, ensuring adequate stone coverage where there is excess asphalt or vice versa.

3.4.2.4.2. Two-layer application of acid emulsion asphalt:

Procedure:

- Clean the road surface with a steam cleaner (or broom).

- Apply the first emulsion layer, the amount of emulsion required depends on the size of the stones and the resin content of the emulsion.

- Spread the first layer of stones, the quantity of stones depends on the size of the stones used. Roll with a pneumatic-tired roller (or 6-8T roller) 1-2 times per point.

- Apply the second emulsion layer, the amount of emulsion

- Spread the second layer of stones, the quantity of stones

- Roll with a pneumatic-tired roller (or 6-8T roller) 3-5 times per point.

After completion of construction, personnel should guide vehicles to limit speed to 20 km/h and adjust to run evenly on the road surface for 15 days to sweep loose stones back into potholes, ensuring adequate stone coverage where there is excess asphalt or vice versa.

Note: quantity of stones, the required amount of acid emulsion for paving two layers see in Appendix 6.

3.4.2.5. Repairing cracks on the road surface (in cases where only the asphalt concrete layer is cracked, not extending down to the underlying layers):

Procedure:

There are two methods:

- The first method:

+ Chisel to widen the crack into a wedge shape

+ Clean out loose materials

+ Pour hot liquid asphalt, emulsion, or solid asphalt into the crack.

+ Trowel in a small aggregate asphalt mixture into the crack.

- The second method:

+ Chisel to widen the crack into a wedge shape.

+ Clean out loose materials.

+ Pour hot asphalt into the crack.

+ Sprinkle sand into the crack, 3-5mm below the original road surface.

+ Pour hot asphalt into the crack a second time.

+ Sprinkle sand into the crack to fill it completely and spread over both sides of the crack 5-10cm.

3.4.2.6. Repairing localized depressions.

3.4.2.6.1. For roads paved with stone chips and asphalt or asphalt impregnated gravel:

Depending on the depth of the depression, proceed with the repair.

- In cases where the depth of the depression is from 3-6cm: repair similar to patching potholes using an oil-modified asphalt mixture or BTNN (3.4.2.3.1) or hot asphalt patching (3.4.2.3.2).

- In cases where the depth of the depression exceeds 6cm: repair using three-layer hot asphalt paving with standard stone chips, with an asphalt quantity of 4.5 kg/m² (According to the Technical Construction and Acceptance Standards for Asphalt Paving Roads 22TCN 271-01).

Procedure:

+ Place stone chips to the required elevation, taking into account a compaction factor of 1.3

+ Roll to achieve 100% of Stage 2 compaction of the stone chip water-bound macadam road (According to the Technical Construction and Acceptance Standards for Stone Chip Water-Bound Macadam Roads 22 TCN 06-77), note that no water should be applied, no sand should be spread, and this layer of stone chips must be compacted firmly and leveled.

+ Apply the first layer of asphalt, quantity of asphalt 1.9 kg/m².

+ Spread stone chips 16/20, quantity of stone chips 18-20 liters/m².

+ Roll with a 6-8T roller, 6-8 passes per point.

+ Apply the second layer of asphalt, quantity of asphalt 1.5 kg/m²

+ Spread stone chips 10/16, quantity of stone chips 14-16 liters/m²

+ Roll with a 6-8T roller, 6-8 passes per point.

+ Apply the third layer of asphalt, quantity of asphalt 1.1 kg/m².

+ Spread stone chips 5/10, quantity of stone chips 9-11 liters/m².

+ Roll with a 6-8T roller, 4-6 passes per point.

3.4.2.6.2. For asphalt concrete surfaces:

- Apply the second layer of asphalt, quantity of asphalt 1.2 kg/m².

- Apply a tack coat with hot asphalt (quantity of asphalt 0.5 kg/m²) or acid emulsion with equivalent asphalt content.

- Use a small vibratory roller of 0.8T to compact 3-4 times per point at a speed of 1.5-2 km/h.

Asphalt-coated gravel or gravel impregnated with asphalt surface:

3.4.2.7. Repairing asphalt surfaces with flaking

Repair by applying two layers of hot asphalt, quantity of asphalt 2.7-3.0 kg/m² (depending on the extent of the flaking), similar to the method described in section 3.4.2.4.1.

3.4.2.8. Repairing asphalt surfaces with "wearing out"

Over time, asphalt surfaces gradually lose their protective layer and become exposed. This phenomenon is called "wearing out" of the asphalt surface. Repair by:

3.4.2.8.1. In cases where daily traffic is less than 150 vehicles:

Apply one layer of hot asphalt (According to the Technical Construction and Acceptance Standards for Asphalt Paving Roads 22TCN 271-01).

Procedure:

- Apply the second layer of asphalt, quantity of asphalt 1.2 kg/m².

- Apply asphalt quantity 1.5 kg/m².

- Spread stone chips 10/16, quantity of stone chips 15-17 liters/m².

Treat by laying two layers of asphalt in the form of hot asphalt (according to Construction and Acceptance Standards for Hot Asphalt Surface 22TCN 271-01) or laying two layers with acid emulsion asphalt (according to Construction and Acceptance Standards for Gravel and Gravel Mix Hot Acid Emulsion Asphalt Surface 22 TCN 205-98).

3.4.2.8.2. In cases where daily traffic is 150 vehicles or more:

Apply two layers of hot asphalt, quantity of asphalt 2.7-3.0 kg/m² (depending on the extent of damage), similar to the method described in section 3.4.2.4.1, or apply two layers of acid emulsion similar to the method described in section 3.4.2.4.2.

3.4.2.9. Repairing localized areas affected by rubber or mud subsidence:

When the road surface is affected by localized rubber or mud subsidence, the subgrade structure of the road surface is partially or completely destroyed, sometimes even soil rises to the surface.

Repair technique:

- Excavate the affected surface, subgrade, and foundation to the hard soil base and compact the foundation soil to ensure K ≥ 98.

- Depending on the old pavement structure, traffic volume, axle load, and climatic conditions, decide on the replacement structure.

If the weather is dry, the foundation soil can be replaced to meet technical standards (Note to divide into layers ≤ 20cm thick to compact to a density K ≥ 98).

If the area is wet or during the rainy season, use sand, preferably coarse sand, for replacement.

- The lower subgrade layer of the road surface can use waste rock (with clay content < 6%), divided into layers ≤ 20cm thick and compacted.

- Replace the upper subgrade layer and the road surface layer according to the structure of the old road surface.

3.4.3. Stone Chip Road Surface

3.4.3.1. Supplementing fine aggregates on the road surface:

During vehicle operation, small stone particles will scatter to the sides of the road and break into powder. It is necessary to frequently supplement fine aggregates (sand and gravel) into the roadbed.

3.4.3.2. Patching potholes:

Must use suitable sizes of stone chips (depending on the depth of the pothole) to patch potholes on the road surface.

The procedure is as follows:

- Dig out the damaged area to form a square edge, with a minimum depth of 10cm.

- Sweep away loose materials and dust within the damaged area to ensure it is clean and dry.

- Spread stone chips 40/60 or 20/40, leveling according to a compaction factor of 1.3.

- Use a sheep's foot roller or a vibrating roller of 0.8T to compact the stone chip layer tightly.

- Spread stone chips 10/20 carefully.

- Use a sheep's foot roller or a vibrating roller of 0.8T to compact.

- Spread filler material, stone chips 5/10 and crushed stone 2/5mm or clean sand and gravel. First spread larger particles then smaller ones. While spreading, thoroughly sprinkle water and brush the stones into the gaps.

- Use a sheep's foot roller to compact 8-10 times per point or a small vibrating roller of 0.8T to compact 3-4 times per point at a speed of 1.5-2 km/h.

3.4.4. Gravel and Earth Road Surfaces

3.4.4.1. Supplementing fine aggregates on the road surface: Follow the procedure outlined in section 3.4.3.1.

3.4.4.2. Spraying water to control dust:

To minimize dust when vehicles travel through residential areas on dry days, water spraying is required, depending on weather conditions, at least once a day.

3.4.4.3. Preventing slipperiness:

- Remove the muddy layer

- Spread gravel or waste rock in areas prone to slippage.

- Roll with a 6-8T roller.

- Clear drainage ditches.

3.4.4.4. Removing waves

- Remove wave formations. If there are many continuous waves, remix the surface layer in the affected area.

- Use a grader to restore the super-elevation, crown, and flatness of the road surface.

- Roll with an 8-10T roller.

3.4.4.5. Patching potholes and localized depressions

- Square off the edges and create a minimum depth equal to the depth of the damage.

- Irrigate water (if the pothole area is excessively dry).

- Spread aggregate, level (compaction factor 1.3).

- Use a vibratory roller or a 0.8T drum roller to compact the aggregate layer tightly; watering may be necessary to ensure optimal moisture content during compaction.

3.4.4.6. Rubber and soft soil settlement treatment:

- Excavate and remove the rubberized road base down to solid ground and compact the foundation soil to ensure K ≥ 95.

- Use foundation soil meeting technical standards or sand, lime slag, broken bricks, etc., in layers no thicker than 20 cm, compacted tightly with K ≥ 95.

- Spread a surface aggregate layer, 10-20 cm thick, compacted tightly with K ≥ 95, ensuring the road surface is properly shaped.

3.5. Retaining walls and earth retaining structures

Retaining walls and earth retaining structures are types of construction used to prevent landslides and ensure the stability of the roadbed. The work includes the following items:

3.5.1. Dry-stacked stone and rock gabion retaining walls

- Clear vegetation to prevent overgrowth

- Supplement loose stones at missing locations and replace broken steel wires.

- Drain water to prevent it from flowing into the retaining wall area.

- Regularly inspect and monitor changes in deformation of the retaining wall.

- Repair cracks and breaks with cement mortar mix 100 (if present).

3.5.2. Reinforced concrete and rubble retaining walls

- Strengthen and repair damaged sections of the retaining wall.

- Repair cracks with cement mortar mix 100 (if present).

- Rebuild broken sections using rubble masonry with cement mortar mix 100 (or pour reinforced concrete grade 200).

- Clear vegetation to prevent overgrowth.

- Regularly inspect and monitor.

3.6. Overflow channels and culverts

Includes the following tasks:

3.6.1. Repair cracks with cement mortar mix 100, rebuild broken sections on the slope top using rubble masonry with cement mortar mix 100.

3.6.2. Replace or adjust asphalt concrete paving slabs to ensure a flat surface.

3.6.3. Paint and mark water level markers and signposts for easy observation of water levels.

3.6.4. Repair and replace broken or missing signposts.

3.6.5. Clean out sediment, debris, and branches from the culvert and upstream/downstream areas.

3.6.6. Supplement loose stones in the erosion protection section of the overflow channel and culvert slope.

3.6.7. Supplement loose stones on the culvert and overflow channel road surface after each flood (for culverts and overflow channels with a rubble surface).

3.7. Tunnels

A tunnel is a modern integrated transportation structure including various facilities such as traffic tunnels, ventilation tunnels, escape tunnels, equipped with systems for traffic services like lighting, communication, ventilation, drainage...

3.7.1. For conventional tunnels

Work includes the following items:

3.7.1.1. Tunnel lining:

- For natural rock tunnel linings, regular inspections must be conducted; if damage, weathering, or seepage is found, report to superiors, conduct inspections, and develop repair plans.

- For concrete, reinforced concrete, and rubble tunnel linings:

+ Regular inspections are required; if cracks are found, mark them with gypsum stickers or cement mortar to monitor and report to superiors.

+ If seepage occurs, investigate the cause, check the upper drainage system, and repair immediately while reporting to superiors and proposing remedial measures.

+ Small damages to concrete and rubble must be repaired to maintain aesthetics.

3.7.1.2. Drainage system

The tunnel drainage system includes longitudinal gutters, crown gutters, undercarriage gutters, work includes:

- Clear vegetation, remove weeds, clean sediment and deposited soil in the gutter and catchment pits to ensure good drainage.

- For underground gutters, if poor drainage capacity is detected, causes should be investigated and repairs made promptly.

- Any damaged parts of the concrete and rubble drainage system must be repaired. Longitudinal gutters in the tunnel with concrete covers must have their damaged covers replaced immediately to ensure pedestrian safety. Water pipes that are severely corroded or not functioning well must be replaced.

3.7.1.3. Maintenance and repair of lighting systems

The lighting system includes light bulbs, lampshades, light poles, wiring, electrical cabinets, circuit breakers, generators, substations...

- Replace burnt-out light bulbs immediately, ensuring a minimum of 90% operational lights.

- Light poles and lampshades that rust must be repainted (every 3-5 years) and replaced if damaged.

- Electrical equipment such as generators (substations), circuit breakers, electrical cabinets, wiring... must be maintained and repaired according to electrical industry regulations.

3.7.2. For modern tunnels

Maintenance and repair work for this type of tunnel is specified separately based on specific cases.

3.8. Ferry landing approach roads

Maintenance and repair work for ferry landing approach roads is similar to those for corresponding road types.

Note: Timely repair of damage at the end of the landing (landing apron) due to erosion and impact force from vehicles boarding and disembarking the ferry.

3.9. Emergency evacuation routes

Work includes:

3.9.1. Repaint or reapply reflective strips on faded emergency route signs to make them clear and visible, helping drivers easily enter the emergency route when encountering incidents.

3.9.2. Remove obstacles (mud, fallen rocks...) from the emergency route, especially where it meets the main road.

3.9.3. Clear drainage ditches.

3.9.4. Supplement gravel, sand, and pebbles on the emergency route.

3.9.5. Reshape the emergency route surface (especially after rain, the surface sand layer often becomes compacted) to ensure sufficient friction as originally designed.

3.10. Drainage culverts

Culverts include various types classified by shape such as round (pipe), slab, box, arch, constructed of reinforced concrete or rubble. The structure consists of three main parts: the culvert body, the upstream water intake, and the downstream outlet (including energy dissipation components of the culvert).

Work includes:

3.10.1. Culvert cleaning

Scoop out sediment and rocks deposited in the upstream water intake, inside the culvert, and downstream to ensure smooth water flow through the culvert.

3.10.2. Minor repairs with cement mortar mix 100

- Repair cracks in the joints, headwall, wingwall, downstream apron, and arch roof of rubble masonry culverts using cement mortar mix 100.

If the construction structures or concrete structures are broken, they must be rebuilt using rubble masonry with cement mortar grade 100 or poured concrete grade 200 to restore the original condition.

3.10.3. Clearing upstream and downstream flow of culverts

Includes the following works:

- Excavating sedimented soil and sand in the flow

- Clearing trees and grass on both sides of the flow, at both ends of the culvert to ensure good drainage.

3.10.4. Lime washing the culvert headwall

Lime wash twice a year around the culvert headwall every four months.

3.11. Bridges

The general requirements for bridge maintenance work aim to promptly repair damages to structural components directly affecting the safety of the bridge and traffic safety.

Work includes:

3.11.1. Bridge deck

- Clean the bridge deck and the drainage system on the bridge deck, replace damaged drainage pipes.

- Paint the bridge railings every 2-3 years.

- Lime wash the bridge railings, once every four months.

- Maintain the lighting system on the bridge (if any).

- Repair minor damage to pedestrian paths on the bridge (if any).

- Repair minor damage to the bridge deck.

Depending on the type of bridge deck structure, including:

+ For asphalt concrete (AC) bridge deck: patch potholes (if any) similarly to AC road surfaces.

+ For concrete bridge deck:

— Repair minor damages similar to those on concrete road surfaces.

— Repair expansion joints between concrete slabs.

— Replace broken or perforated slabs, re-level them for stability.

+ For wooden bridge deck:

— Replace wooden parts that are rotten, broken, or damaged.

— Tighten bolts on the wooden deck panels and repair them to ensure solidity.

3.11.2. Expansion Joints

- Ensure that the expansion joints between the two ends of the beams always allow normal movement of the beams.

- Any hard objects falling into the expansion joints must be immediately removed.

- Measures must be taken to prevent water from the bridge surface from flowing into the expansion joints.

- Expansion joints must be regularly cleaned.

- Regularly tighten the bolts connecting the expansion joints to the beams, supplement rubber caps (for rubber expansion joints) and straighten any bent steel plates (for steel plate expansion joints).

3.11.3. Bridge Beams

- For reinforced concrete (RC) and prestressed concrete (PC) structures:

+ Clean and apply waterproofing material or cement mortar to areas where the beam surface concrete has aged or become moldy due to water seepage or environmental factors.

+ For RC beams with cracks larger than the allowable limit 0.2 ≤ Δ ≤ 0.3 mm must be repaired with cement mortar. If the crack is larger, specific solutions will be applied but must be marked with gypsum or cement mortar for monitoring.

+ Clean and repair areas where the concrete is damaged or defective to their original state.

+ Clean and repair exposed and rusted reinforcing bars to their original protective layer thickness using materials such as SIKA or epoxy resin mixed with cement (in proportions specified by the manufacturer).

+ For PC beams if there are cracks, they must be marked with gypsum or cement mortar for monitoring.

- For steel beams, steel trusses, and composite steel-concrete structures:

+ Regularly clean the ends of the beams (especially the outermost beams) which are prone to rust due to debris accumulation.

+ At the connections of the beams and trusses (especially the lower connections) must be kept clean and well-ventilated. Absolutely no water should accumulate at these connections.

+ Repaint areas where paint has been scratched off due to impact with anti-rust paint (two layers), followed by a coat of exterior paint.

+ Clean rusted areas (using a wire brush) before repainting as above.

+ Retighten loose bolts; replace damaged bolts and nails with new precision bolts of the same size.

+ If the RC slabs on the steel beams have shifted, use rubber shims to secure them (if traffic is restricted, use SIKA or epoxy resin to fill the gaps).

3.11.4. Bridge Bearings

There are two types of bearings: steel and rubber; works include:

- Clean the bearing surface.

- Lubricate the entire bearing (for steel bearings) annually.

3.11.5. Abutments and Piers

- Clean the top surface of abutments and piers.

- Patch cracks and spalled mortar joints of abutments and piers and one-quarter of the pier cap with cement mortar grade 100.

- Clear vegetation around the abutment walls, one-quarter of the pier cap, and within 20 meters upstream and downstream of the bridge.

- Clear debris and remove floating debris caught on the abutments and piers.

- Repair steps leading up to the bridge and repaint anti-rust paint on inspection ladders (if any).

3.11.6. Approach Roads

- Repair the approach road surface.

- Clear vegetation on the approach road embankment, 10 meters on each side from the end of the abutment.

- Adjust and supplement signs, guideposts, elevation markers, and guardrails at both ends of the bridge that are tilted, cracked, or missing.

- Repaint faded signs every 2-3 years.

- Fill in deficiencies in the approach road subgrade.

3.11.7. Flow Direction Structures and Protective Structures

- Patch cracks and spalled mortar joints of flow direction structures and protective structures with cement mortar grade 100.

- Clear vegetation around the flow direction structures and protective structures.

Note: Maintenance of suspension bridges has separate regulations.

3.12. Management Service Facilities

Management service facilities include: Highway management offices of units responsible for highway management and maintenance; Bridge guard stations; Traffic counting stations; Toll booths; Overweight vehicle detection stations.

Maintenance of management service facilities includes two parts:

- Maintenance and repair of building structures (houses): According to Circular No. 05/2001/TT-BXD dated August 30, 2001 guiding maintenance of construction projects.

- Maintenance and repair of installed equipment will be carried out according to the specific regulations of the manufacturers.

3.13. Road Sign System

According to "Traffic Sign Regulations 22 TCN 237-01" issued by the Ministry of Transport through Decision No. 4393/2001/QĐ-BGTVT dated December 20, 2001, the road sign system is defined as all means used for signaling, directing, commanding... for motor vehicles, non-motorized vehicles, and pedestrians on roads to ensure traffic order and safety.

The requirement for maintaining the road sign system is to ensure it remains bright, clean, with clear symbols, not faded or dirty, and in its original design state.

3.13.1. Signs

Includes the following items:

- Paint signs (poles and back of signs) every 2-3 years.

- Replace or reapply reflective coating on damaged surfaces of signs.

- Replace or supplement missing or broken signs.

- Adjust, repair signs that are bent or tilted; reposition signs that are leaning to ensure they are straight, correctly placed, and clean their surfaces to ensure clarity and visibility.

- Remove and clear obstacles that obstruct signs.

3.13.2. Road markings

Road markings are a form of signaling to guide and control traffic, aiming to enhance traffic safety and capacity.

Therefore, road markings must be clear and free from dust accumulation; if faded, they should be repainted. Repainting frequency: once every two years. If using reflective hot spray paint: once every three to five years.

3.13.3. Forced deceleration strips

- Repair damaged areas with black gravel or BTNN material like patching potholes.

- Repaint faded stripes once every two years. If using reflective hot spray paint: once every three to five years.

3.13.4. Speed humps

Repaint worn areas with reflective hot spray paint: once every three to five years.

3.13.5. Reflective nails

- Replace missing or damaged reflective nails.

- Clean the surface of reflective nails.

3.13.6. Convex mirrors

- Repaint faded mirror posts every two to three years.

- Replace cloudy or broken convex mirror panels.

- Clear vegetation to ensure clear visibility for mirrors.

3.13.7. Traffic islands

Traffic islands are arranged at intersections for the purpose of:

- Diverting traffic flow

- Placing traffic control devices and lighting fixtures.

The structure of traffic islands: the outer edge is usually constructed with concrete pavers or bricks, marked with vertical lines. Inside, it is filled with soil for planting grass, flowers, and ornamental plants (in urban areas) or covered with cement mortar.

Maintenance work on traffic islands includes:

+ Maintaining grass and plants to keep them healthy and attractive.

+ Repairing directional signboards attached to the island.

+ Repairing damaged edges caused by vehicle impacts.

3.13.8. Guardrails

- Guardrails made of concrete or stone, including the following tasks:

+ Lime wash once every four years.

+ Patch and repair cracked or broken sections with rubble masonry cement mortar mac 100 or BTXM mac 200.

+ Clear vegetation to prevent overgrowth.

- Guardrails made of corrugated steel, including the following tasks:

+ Straighten and replace damaged sections due to vehicle impacts.

+ Repaint rusted sections of corrugated steel every two to three years (except for galvanized corrugated steel).

+ Clean reflective eyes attached to columns.

+ Replace missing or damaged reflective eyes.

+ Tighten loose bolts or replace missing bolts and nuts.

3.13.9. Flexible median strips Including the following tasks:

+ Repaint concrete pillars and steel pipes every two to three years.

+ Replace broken concrete pillars and bent steel pipes.

+ Adjust flexible median strips that have shifted to ensure they are straight and properly positioned, maintaining aesthetics.

3.13.10. Rigid median strips made of BTXM

- Repaint faded stripes every two to three years.

- Regularly clean reflective eyes attached to the top of the median strip (if present).

3.13.11. Markers, MLG posts ... contents include:

- Straighten and adjust markers and MLG posts that are tilted.

- Supplement and replace broken or missing posts.

- Paint: once a year.

- Lime wash: once every four years.

- Clear vegetation to prevent overgrowth.

3.13.12. Kilometer posts

Kilometer posts are used to determine the distance of each section and route, guiding users about distances along the way. They are cast in reinforced concrete or steel plates. The base is made of BTXM, stone, or steel pipe.

Maintenance work on kilometer posts mainly includes the following tasks:

- Paint kilometer posts once a year.

- Paint or apply reflective tape on faded or lost kilometer posts (if present).

- Replace broken or damaged kilometer posts.

- Clear vegetation to prevent overgrowth.

3.13.13. Water level markers

- Water level markers are a type of marker placed at the following locations:

+ Bridge abutments: to indicate water depth and clearance height for navigation.

+ Both ends of overflow roads, underground roads, and flooded sections to indicate flood depth.

- Water level markers are made of flat steel sheets, steel pipes, or poured reinforced concrete, painted with specified bands.

- Repaint water level markers once a year.

3.13.14. Traffic signal systems

Traffic signal systems are managed by the traffic police department. The regular maintenance procedures for traffic signal systems are separately defined.

3.13.15. Lighting systems

Lighting systems on roads and bridges are maintained according to regulations set by the electrical industry.

Note: Paint used for road marking signals is specialized paint meeting technical requirements as per the "Liquid Traffic Signal Paint on BTXM and BTN 64 TCN-92-95" standard issued by the Ministry of Industry in 1995. Hot spray paint has technical requirements as per manufacturer guidelines.

3.14. Tree maintenance

3.14.1. Trees along the roadside

On roads where trees are planted, they must be cared for and maintained to ensure shade, aesthetics, and traffic safety, including the following tasks:

- Prune branches and cut down dead trees, diseased branches at risk of breaking, and trees affecting traffic safety. This should be done before the annual rainy season.

- Lime wash: apply lime whitewash around the tree trunk twice a year, up to a height of 1.0-1.5 meters above ground level, once every four years.

3.14.2. Trees planted on central median strips

Trees planted on central median strips (on roads with separate lanes for opposing traffic) serve to block headlight glare and enhance aesthetics. These are typically ornamental shrubs or easily shaped plants (such as crabapple, flowering cherry, and waxberry), planted in continuous rows or clusters.

Maintenance work on trees planted on central median strips includes the following tasks:

- Watering and caring for the trees: using specialized watering vehicles or manual watering, depending on the season (dry or rainy) to ensure proper growth.

- Planting replacement trees for those that have died or been lost.

- Pruning branches to shape the trees and trim grass; requirements:

+ The trees must maintain aesthetic appeal, not allowing branches or grass to extend beyond the concrete curb.

+ Trees should not exceed 1.3 meters in height from the curb level.

3.14.3. Trees planted on unused land reserved for roads

Plants grown on non-road reserved land strips are shrubs that can be easily shaped into ornamental forms, serving both to beautify the environment and protect the road reserve from encroachment. Additionally, they provide sources of seedlings for replacing dead or missing plants on central median strips.

For some coastal road sections, plants grown on non-road reserved land strips also serve to block waves, sand, and wind.

Maintenance work for plants on non-road reserved land strips, if they are ornamental plants as mentioned in Section 3.14.2. If they are wave-blocking, sand-blocking, or wind-blocking plants, maintenance work follows the procedures outlined in Section 3.14.1.

Chapter 4.

ACCEPTANCE AND EVALUATION OF RESULTS

4.1. Acceptance Work

As regular and continuous road maintenance is required, acceptance must be分级后，最后一部分的翻译如下：

4.1.1. Acceptance at the District Road Management Office level

The District Office must regularly inspect, urge, and provide technical guidance to workers to ensure continuous road maintenance activities, promptly rectify and repair any errors. Unauthorized encroachments and violations of road safety zones must be detected and dealt with promptly.

Weekly, the District Office accepts the work of each Team or individual worker.

4.1.2. Acceptance at the Company (Section) level

Each month from the 20th to the 30th, the Company (Section) organizes acceptance of road maintenance work for the District Road Management Offices.

4.1.2.1. Members of the Company (Section) Acceptance Committee include:

- Company (Section) leadership – Chairperson

- Head of the Traffic Management Department – Member

- Representatives from planning departments and directly supervising staff of the Company – Members

- Head of Station – Member

4.1.2.2. Basis for acceptance

- The monthly road maintenance assignment agreement between the Company (Section) and the Station, and the implementation status of the assignment by the Station.

- Acceptance criteria for road maintenance work (Annex 7).

- Receipts and delivery documents for materials and fuel. Payment vouchers for salaries and other expenses.

4.1.2.3. Content of acceptance

- On-site inspection at the Station Office:

+ Management of bridge and road file records and updating of project developments into files, diagrams, and related forms concerning the road route.

+ Implementation of bridge and road patrol, traffic inspection, and protection of road safety zones (through records and documents kept at the Station).

+ Completion quantity confirmation certificates signed by the Company's (Section) staff overseeing with the Stations, and acceptance certificates of the Station with the Teams (or workers).

+ Implementation status of directives and guidelines from the Company (Section), the Road Management Zone (Department of Transport, Construction and Transportation), and other related issues assigned to the Station.

- On-site acceptance, inspecting the implementation status, comparing with the assigned documents, and evaluating quality, aesthetics, and environmental aspects.

4.1.3. Acceptance at the Road Management Zone level (Department of Transport, Construction and Transportation)

- From the 25th of the last month of each quarter to the 15th of the first month of the next quarter, the Road Management Zone (Department of Transport, Construction and Transportation) will conduct acceptance and payment for road maintenance work for the Companies (Sections).

- Acceptance based on approved objectives and quantities.

4.1.3.1. Basis for conducting acceptance

- The quarterly road maintenance work budget approved by the Road Management Zone (Department of Transport, Construction and Transportation); the assigned objectives and quantities in the approval.

- Evaluations and comments from inspections conducted by the Road Management Zone (Department of Transport, Construction and Transportation).

- Prior to the acceptance committee meeting, there must be a technical acceptance between the Road Management Zone (Department of Transport, Construction and Transportation)'s supervising staff and the Company, this step must be fully completed.

- Actual conditions of bridges and roads and the internal acceptance results of the Company (Section) with the Road Management Stations each month.

- Acceptance criteria for road maintenance work (Annex 7)

4.1.3.2. Composition of the acceptance committee:

- Leader of the Road Management Zone (Department of Transport, Construction and Transportation) – Chairperson

- Leader of the Traffic Management Department – Deputy Chairperson

- Representatives from some business departments and supervising staff of the Road Management Zone (Department of Transport, Construction and Transportation) – Members.

- Team leader of the Traffic Control Team in the area – Member

- Leaders and representatives from some business departments of the Company (Section) – Members

4.1.3.3. Content of acceptance:

- At the Company (Section) office:

Inspection and acceptance of file management work for bridge and road administration, recording and updating changes of projects into files. Implementation status of bridge and road patrols, reporting on bridge and road conditions (through records kept at the Company, Section).

- On-site:

+ Overall acceptance of the entire route to evaluate the general condition of road maintenance work, management of road safety zones, road sign systems (marker posts, warning signs...), drainage systems.

+ Detailed acceptance of selected sections of roads and bridges according to reports from the overseeing staff. Selected kilometers of roads and bridges are inspected and accepted randomly to ensure objectivity.

4.1.4. Sample of the acceptance certificate for road maintenance work (Annex 8)

4.2. Evaluation of the implementation results of road maintenance work

4.2.1. Based on the road maintenance work assignment agreement given by the Road Management Zone (Department of Transport, Construction and Transportation) to the Company (Section), compare the assigned objectives and the actual implementation status of the Company (Section) for each work item to conduct evaluations at levels of Excellent, Good, Average, and Poor (in the table below):

4.2.2. Along with grading and classifying as Excellent, Good, Average, or Poor, a record of deficiencies requiring the management and maintenance unit to continue addressing should be established. (Annex 9)

Chapter 5.

SAFETY MEASURES FOR TRAFFIC DURING ROUTINE MAINTENANCE ON ROADS

Routine maintenance on roads must absolutely ensure traffic safety for workers, road users, and vehicles.

The main safety principles to be applied during construction on motor vehicle roads are detailed in the "Regulations on Construction of Works on Exploited Roads" stipulated in Decision No. 4213/2001/QĐ-BGTVT dated December 10, 2001 issued by the Minister of Transport, noting the following points:

5.1. Workers working on the road must wear reflective protective clothing as prescribed.

5.2. During construction, warning signs for the construction site, speed limit signs... must be placed at a distance of 50-150 meters from the construction location depending on the speed of vehicles on that road.

5.3. Traffic guidance personnel must be fully equipped with flags, whistles, and identification badges.

5.4. The construction area must be fenced off. Workers performing routine maintenance on roads and repair equipment may only be placed and moved within the fenced-off area.

5.5. Red lights must be used to signal at night. On busy routes with high vehicle speeds, signaling lights must also be used even during daytime construction.

Chapter 6.

LABOR SAFETY

6.1. Labor Safety in Routine Road Maintenance

During routine maintenance on roads, the following procedures and regulations must be followed: VN14-79 Regulation attached to Decision No. 60/QĐ-LB dated February 23, 1970 of the Ministry of Labor - State Committee for Science and Technology, Regulation 2289-78 on labor safety. Noting the following points:

6.1.1. When patching potholes, handling rubber, filling depressions, sweeping the road, painting road markings, ... on the road surface and trimming trees and grass on median strips, traffic safety must be ensured (as stipulated in Chapter V), while ensuring labor safety for workers operating on the road.

6.1.2. When working on high embankments, safety belts must be worn. When working at the base of the embankment, attention must be paid to the possibility of soil collapse or falling rocks from the embankment.

6.1.3. When cooking asphalt, labor safety requirements must be met according to the provisions in "Construction and Acceptance Procedures for Asphalt Pavement Surface 22TCN 249-48"; "Technical Standards for Construction and Acceptance of Asphalt Paving Surface 22TCN 271-01"; noting the following:

- Before pouring asphalt into the drum or pot, it must be checked to ensure there is no residual water and that operations can proceed smoothly.

- During the preparation and cooking process, ensure that no danger arises from water falling into the cooking pot.

- While cooking, be careful not to allow hot liquid asphalt to splash onto people.

- During cooking, the drum should contain only 75-80% of its volume. The temperature of the cooked asphalt should not exceed 160°C.⁰4. Liquid bull semen

Particularly when cooking asphalt for oil-modified asphalt production, follow the "Technical Process for Producing and Using Oil-Modified Asphalt in Road Surface Repair 22TCN 21-84", with the temperature of the asphalt before mixing not exceeding 140°C and under no circumstances should oil be added during mixing.⁰When transporting hot asphalt, the container must be securely covered.

6.1.4. For manual application of asphalt, carefully check the scoop, handle, and bucket strap to ensure safe scooping and spreading of asphalt. If using a hand-held spray machine, it is essential to check the operation of the machine and nozzle before spraying.

6.1.5. When applying asphalt, move backward against the wind direction. Workers must be fully equipped with protective gear (rubber boots, gloves, masks, etc.).

6.1.6. 6.2. Labor Safety in Routine Bridge Maintenance

Adhere to the relevant provisions in the "Labor Safety Regulations for Bridge Construction 22TCN3-81," Decision No. 1125/LĐTL dated March 21, 1973 of the Ministry of Transport, VN14-79 Regulation attached to Decision No. 60/QĐ-LB dated February 23, 1970 of the Ministry of Labor - State Committee for Science and Technology on labor safety in bridge construction, Regulation 4086-85 on electrical safety in construction, Regulation 3146-86 on welding safety, Regulation 4245-86 on oxygen and acetylene production safety, Regulation 2292-78 on painting work safety. Noting the following points:

People suffering from heart disease, poor eyesight, deafness, or nervous system weakness, mental illness, or alcohol consumption shall not work at heights.

6.2.1. When cleaning rust, painting, repairing beams, welding crossbeams, frames, bridge bearings, or replacing parts of the bridge, scaffolding must be securely installed for movement and to prevent falling objects. Scaffolding must be thoroughly inspected and confirmed safe before use.

6.2.2. It is forbidden to wear hard-soled shoes, sandals, or backless slippers at the construction site. When working at heights, wear rubber-soled shoes, and when cleaning rust, painting, or repairing bridges, wear safety belts, masks, and gloves.

6.2.3. 6.3. Labor Safety in the Use of Machinery and Equipment

Follow the "Safety Regulations for Pressure Equipment VN2-75" attached to Decision No. 375/QĐ-LB dated December 31, 1975 of the Ministry of Labor - State Committee for Science and Technology, Regulation TCN 32-83 on pressure cylinder safety, Regulations 2290-78, 5659-92 on production equipment safety, Regulation 5181-90 on compressed air equipment safety, Regulation 5419-91 on handheld machinery safety, Regulation 5658-92 on automobile safety, Regulation 3148-79 on conveyor belt operation safety, Regulation 4717-89 on protective equipment safety, Regulation 4756-89 on grounding and bonding safety of electrical equipment. Noting the following points:

All types of machinery and equipment used in routine road maintenance must have a history record, maintenance and usage instructions, shift handover logs, and daily technical condition monitoring logs to ensure worker safety.

6.3.1. Moving parts of machinery (drive shafts, rollers, pulleys, gears, chains, friction discs, couplings, joints...) must be properly shielded.

6.3.2. Any safety devices listed in the machinery's history or newly added must be fully installed and maintained in good condition. In case of damage, they must be repaired immediately.

When machinery is operating or moving on the road, audible or visual signals must be provided. Warning signs or barriers must be set up within the machinery's operational range.

6.3.3. Machinery powered by electric motors must:

6.3.4. - Be grounded according to current regulations for all metal parts of the machine.

- Be connected to insulated power cables from the power source to the machine. If not mounted on a pole, the cable must be run through a protective conduit.

- Connect the rubber-insulated power supply cable to a pole or support structure. If not connected to a pole, it must be placed inside a protective conduit.

- There must be a box for the circuit breaker and it should be placed in a convenient location, in a dry area with a lock to ensure safety. In case of power outage, the circuit breaker must be turned off to prevent electric motors from starting unexpectedly when power returns.

6.3.5. When the machine is operating, cleaning, lubricating oil, and repairing any part of the machine are strictly prohibited.

6.3.6. The location where the machine is placed must have adequate fire prevention measures according to the current fire protection regulations. The area of machine operation must be adequately illuminated.

6.3.7. Workers operating the machine must be trained in technical safety. When working, they must have full personal protective equipment as prescribed by current state regulations.

6.4. Occupational Safety in Material Extraction

In material extraction work serving road construction, compliance with Regulation 5178-90 on open-pit mining and stone processing, Safety Regulations for the storage, transportation, and use of explosives issued together with Decision No. 80/TTg-CN dated August 15, 1968 of the Prime Minister's Office, Decision No. 617/BXD-VKT dated September 19, 1978 of the Ministry of Construction on sand, gravel, and stone production, Regulations 3255-86, 5279-90 on fire and explosion safety must be observed. Special attention must be paid to the following points:

6.4.1. Units transporting, storing, and using explosives for rock extraction must comply with Safety Regulations for the storage, transportation, and use of explosives.

6.4.2. Drilling holes and blasting must be carried out strictly according to the design and blasting passport approved by the competent authority.

6.4.3. Blasters must be trained and certified. Those involved in the storage, transportation of explosives must be fully educated on safety regulations.

6.4.4. When workers manually load rock onto trucks, they must load from the top down of the rock pile and stand on one side of the truck. Rock loading onto improved vehicles must not exceed the height of the vehicle sides, and during transportation, constant vigilance must be maintained to prevent rocks from falling and rolling over feet.

6.5. Personal Protection During Work

6.5.1. While working, workers engaged in road construction must wear appropriate labor protective clothing as stipulated and suitable for their tasks.

Personal equipment must comply with Decision No. 38/LDTBXH-QD dated January 19, 1990 of the Ministry of Labor, Invalids, and Social Affairs, Regulation 1600-83 on protective clothing for men, Regulation 1601-83 on protective clothing for women, Regulation 5039-90 on eye protection devices, Regulation 5111-90 on determining the ability to work while using personal protective equipment, Regulation 3156-70 on hand protection devices, Regulation 3155-79 on leather and fabric protective work shoes, Regulation 1598-74 on dust masks.

6.5.2. Workers performing patrol duties must wear uniforms specified in "Regulations on the Organization and Operation of Patrols Issued Pursuant to Decision No. 2044/QD-GT dated September 5, 2000 of the Vietnam Highway Administration."

Chapter 7.

ENVIRONMENTAL PROTECTION

7.1During road construction and maintenance, strict adherence to the Environmental Protection Law and Decree No. 175/CP dated October 18, 1994 of the Government guiding the implementation of this Code must be ensured.

7.2. During construction, good hygiene, safety rules must be followed, avoiding water and air pollution. Transport vehicles carrying materials must be covered to prevent spillage on the road.

7.3. Rubber or asphalt should not be used for heating. Specialized pots must be used for heating asphalt with fuel such as wood or coal.

7.4. Asphalt should not be heated in residential areas, on bridge surfaces, or near flammable and explosive materials.

7.5. Hot patching methods for potholes and asphalt surfacing should not be used in residential areas along the route. Alternative technical solutions and materials such as stone-asphalt mixtures with oil, emulsified asphalt concrete, etc., must be used instead.

7.6. Minimize noise and exhaust smoke impacts caused by construction machinery in residential areas during road construction and maintenance by scheduling work times appropriately.

7.7. After completing road construction and maintenance work, the construction site must be thoroughly cleaned and cleared.