EN 22 TCN 306 2003 TECHNICAL STANDARD FOR ROAD MAINTENANCE AND REPAIR

22 TCN 306 2003: TECHNICAL STANDARD FOR ROAD MAINTENANCE AND REPAIR, Issued under Decision No 15272003QDBGTVT dated 28 May 2003 of the Minister of Transport. Tiêu chuẩn ngành 22TCN 306:2003 về tiêu chuẩn kỹ thuật bảo dưỡng thường xuyên đường bộ do Bộ Giao thông vận tải ban hành

Issued under Decision No 1527/2003/QD-BGTVT dated 28 May 2003 of the Minister of Transport

CHAPTER I: GENERAL PROVISIONS

1.1 Scope of Application

- Technical Standard for regular road maintenance shall be applied uniquely throughout the country forthe route managed by the Municipal Government and local government

- This standard does not apply to periodic maintenance work and unscheduled repairs

- For regular maintenance for bridges with a total length of over 300 meters, separate regulation shall

- Decree 167/1999/ND-CP dated 26 Nov 1999 of Government on road management operation

- Decree No 172/1999/ND-CP of December 7, 1999, detailing the implementation of the ordinance

on protection of traffic works with regard to land road traffic works

- Joint Circular 01/2001/TTLT/BTC-BGTVT dated 05 Jan 2001, Guiding the management, payment

and settlement of economic non-business funds for road management and maintenance

- Prevailing technical standards on design, construction and acceptance for road trafficinfrastructure

1.3 Terms and abbreviation definition

- Regular road maintenance: Includes management and regular maintenance in order to protect,

prevent damage and promptly repair minor damages This work is carried out regularly andcontinuously throughout the year, on the entire route to ensure smooth and safe traffic on road

- RM: abbreviation of “regular maintenance”

- CC: abbreviation of “cement concrete”

- AC: abbreviation of “asphalt concrete”

- RC: abbreviation of “reinforced concrete”

- PRC: abbreviation of “prestressed reinforced concrete”

- CAC: abbreviation of “cold asphalt concrete”

- RTI: abbreviation of “road traffic inspectorate”

- PR: abbreviation of “periodic repair”

- IR: abbreviation of “irregular repair”

- M&R: abbreviation of “road management and repair”

- TT: abbreviation of “traffic transportation”

- PT: abbreviation of “public transportaton”

- TF: abbreviation of “traffic safety”

- TA: abbreviation of “traffic accident”

- RM: abbreviation of “road management”

- VR: abbreviation of “Vietnam road”

- ROW: abbreviation of “right-of-way”

- LCS: abbreviation of “land clearing stake”

CHAPTERII: MANAGEMENT

2.1 Document control

Timely archive and supplement documents and materials of the constrction work

2.1.1 Documents and materials include:

- As-build documents, registration records for road and bridge inspection, bridge inspection records

- It should have the archive storage

- It should have measures against damage or loss

- It should have qualified in-charged staffs

2.1.4 The update of additional data into documents and materials should be in accordance with theregulations (regarding to update time, data )

2.1.5 Hierarchical archive of documents and materials:

- Directorate for Road of Vietnam: Arhive initial as-build documents (original) by Decision2578/1998/QD-BGTVT-CGD dated October 14, 1998 of MOT on "Issuance of content and lists ofas-build documents of bridge and road construction works"; bridge inspection records; bridgeprofile records and road registration records

- RM Agency (Department of Transport, PT): Archive initial as-build documents (copies); as-builddocuments for every time of RP and IR Inspection minutes, bridge inspection records; processingminutes against encroachment and violations of road safety corridors and other related documents;bridge profile records and road registration records

- Units in charge of road management and repair: Archive as-build documents for every time of PRand IR Inspection minutes, bridge inspection records; processing minutes against encroachmentand violations of road safety corridors and other related documents; bridge profile records and roadregistration records

2.2 Road safety corridor management:

Responsibility of road safety corridor management:

2.2.1 DRVN: Annually, based on report data from management units, shall conduct the synthesis andanalysis to make plan to submit to competent authorities for approval

- Inspect and supervise the implementation of road corridor safety management

- Propose mechanisms and policies on road corridor safety management submit to competentauthorities for approval

2.2.2 RM Agency (Department of Transport, PT): Carry out the performance, supervise theimplementation of units who directly manage, forces under RTI shall perform their assigned taskswithin the management scope

- Coordinate with local authorities to implement road corridor safety protection

- Make reports in prescribed forms

2.2.3 M&R Agency: Unit who is directly responsible for preserving road safety corridors

- Collaborate with RTI in patrolling, checking and inspection of road corridor safety protection

- Coordinate with local government in preventing the encroachment and violations of road corridorsafety

- Make management records, perform storage and preservation and regularly update on status ofencroachment and violations of road corrdiro safety in the management area

- Monthly, perform the synthesis and and report as regulation

Note: Records of road corridor safety management include:

+ Diagram of stretch which fully show occupied buildings within the scope of road corrirdor safety.+ Handover record with locality on LCS

+ Commitment minutes from households living along the street, not encroaching and violating roadcorridor safety

2.3 Inspection and supervision on technical status of the construction work:

A Road and works on road

2.3.1 Regular inspection:

Perform road patrol 1 time/week In case of detecting any damage to the road which may cause unsafetraffic or traffic jams, the encroachment and violation of road corridor safety, it should report to theCounty to handle and solve For cases beyond the capability, it should timely report to higher roadmanagement agencies

2.3.1.1 Duties:

- Timely detect law violations and infringe on road works, road safety corridors and damage causingunsafe traffic such as house construction, building materials, electric poles, illegal establishment

of shops and pubs in road safety corridors and inform the County’authorities

- Check pavement, bridges, drainage systems, road signaling system and other ancillary works todetect any damage that may cause traffic accidents If the work volume beyond capacity of staff incharge of road patrol, it should inform the superiors to improve the plan

- In case of events causing traffic congestion such as land slide, flood, broken bridges , firstly, itshould take measures to ensure traffic safety (railings, travel prohibition signals ), and findalternatives to ramification and report the superior

- Staff in charged of road patrol should timely repair minor damage of bridge and road which doesnot require a lot of manpower to ensure traffic safety, such as collecting scattered stones on theroad, fixing inclined stakes, cutting tree branches preveting visibility

- Cooperate with road traffic police force and road traffic inspectorate to clear the road in case ofhaving trouble-encoutered vehicles on road (broken machine or accident) to prevent traffic jam.

- Perform statistics and monitor traffic accidents occured on the assigned road section, fully recordthe cause of the accident (if possible)

- Propose repair plan of regular or irregular repair for road and bridge with the County andCompany

- Monitor traffic safety at construction locations; if traffic safety did not satisfied requirements, itshould remind contractors to improve and report to superiors for solution

- Fully record status of bridge and road into "Road patrol daily record" Upon the completion of roadpatrol in the day, road patrol staff shall immediately report to the County all the status of the bridgeand road of that day

2.3.1.2 Equipment: Patrol staff should be equipped in accordance with the unique regulation (seeAppendix 1)

2.3.1.3 Patrol staff should be at least at high school qualification and trained specific profession inorder to accomplish the task He should have good health, highly responsible manner and at least level

4 qualification for worker

2.3.2 Periodical inspection: includes monthly and quarterly inspection

2.3.2.1 Monthly inspection: conducted by M&R Agency with the County’s RM Agency, including thefollowing contents:

2.3.2.1.1 Check internal affairs:

- The status record of road and bridge of the County

- The documents and materials (monitoring records of accidents, traffic flow, road patrol, accountingbooks and statistics ) of the County

2.3.2.1.2 Site inspection:

- Check the damage and degradation status of the road and other works on the road

- Assessment of the Maintenance and Repair of the County

- How to check: simple, visual, using conventional measuring instruments

- Checking scope: the entire route in the jurisdiction of the County; detail as follows:

+ For the pavement:

 Check the positions of settlement, landslide, dangerous high slope sections, locations frequentlysubmerged tin rainy season These positions should have sufficient warning signs, guardfence fordangerous area, or water column

 Check trimming work, additional filling for embankment and curb as prescription

+ For pavement: Check and determine the volume and damage degree on each km: potholes,cracked, concaved, rubbered , particularly at bridge (culvert) approach slab where localsettlement occurred frequently

+ For drainage system:

 Check drainage status of culverts, sand deposition of manhole at upstream, downstream and insideculvert; deterioration of culvert pipes, plates, seamless, top wall, side walls, apron (especiallyapron at downstream where erosion happened frquently )

 Check drainage operation of ditch system, particularly at road sections of significant longitudinalslope which are vulnerable to remarkable erosion, causing danage and unstability to embankment;check the damage of masonry ditch

+ For road signaling system: Check numbers and technical conditions (poles, signboards, convexmirror, flexible median )

+ For dyke work, retaining wall, overflow protection work : Check the stability, the damage of theworks; safety equipment such as water column, poles, signs

2.3.2.2 Quarterly inspection: conducted by RM Agency (Department of Transport, PT) with M&RAgency, including the following contents:

2.3.2.2.1 Check internal affairs:

- The status record of road and bridge of the County

- The documents and materials (monitoring records of accidents, traffic flow, road patrol, accountingbooks and statistics ) of the unit

2.3.2.2.2 Site inspection:

- Check the damage and degradation status of the road and other construction works on the road

- Assessment of the Maintenance and Repair of units under management

- How to check: simple, visual, using professional methods

- Checking scope: the entire route and some random sections or works to assess RM

- In-charge staff should synthesize and evaluate status of each Km, bridge and report to inspectiondelegations

B For bridge

The inspection is to assess working status of the bridge, discover the damage which may cause unsafetraffic and impact on load capacity of the bridge, and monitor the damage which has been marked fromprevious inspections

2.3.1 Frequent checking:

- Conducted by the County’s Head or technical staff authorized by the County’s Head The work is

to understand the work condition and make repair plan

- Check all types of bridge on the route under the management of the unit

- For significant bridges (for particular great bridge, it should have specified rule), it should haveinspection outline to check regularly, and performed by the County’s Head

- Results from frequent checking and measurements from damage monitoring, solutions and volumerequired repairs should be fully into Records of frequent checking of bridge

- When detecting any damage that is deemed to affect the safety of the work, it should immediatelyreport to superiors to make inspection plan and immediate repair, ensuring traffic safety Also, theCounty’s Head should immediately apply temporary measures to keep the work safety and trafficsafety

- Content for frequent checking:

+ Check bridge desk:

 Status of bridge desk cover;

 Drainage condition of bridge desk;

 Status of joints: broken, crushed ?;

 Status of wheel guard, railings;

 Other devices such as signs, lighting columns, protection walls at bridge approach slabs.+ Check bridge girders:

 For steel structures: Check status of beams and steel girders (bent, deformed, twisted,broken ?); status of paint and erosion of steel girders; status of links and joints of girders; status

of bolts, joint rivets and rusty condition of structural parts

 For RC and PRC or combined steel beams:

Check the status of cracking, chipping, breaking, peeling out of the concrete;

Check the status of rust and deterioration of reinforcing steel;

Waterproof status, water leakage under beam flange and bridge deck

 For arch structure: Status of crack, break of grout and waterproof at the bottom of the arch.+ Check bearings:

 Check the deformation, corrosion, chipping of rollers, studs of bearing, horizontaldisplacement of rollers, the incline and deflection of rollers along bridge centerline for steelbearing type;

 Check the aging and deformation of rubber bearings;

 Check the flatness, cleanliness and ventilation of bearings;

 Check greasing work for bearings

+ Check abutments, piers:

 Check status of cracks, mortar joint, rip-rap; weathering and corrosion of concrete ofabutment body and and pier body;

 Check the erosion at foundation of abutments and piers; the inclination, displacement andsettlement of the abutments and piers;

 For all test cases, it should check horizontal crack of the abutment, particularly piers whoseheight on the curve; check exposed part due to erosion;

 Check cutoff dike and quarter cones;

 Check road pavement behind abutments

+ Check protection works and flow regulation works such as channel direction dike, protection works

of approach roads, river embankments etc It should pay attention to the stability of these works (nobreak, landslide, inclination, settlement) and evaluate the effectiveness of such works

2.3.2 Periodical inspection:

- Annualy, perform 2 inspections: before and after storm season Upon the inspection, it shouldcheck in detail the tructural parts of the works It is required to have specialized equipments forintestigation and measurement

- Check before storm season: Focusing on abutment, quarter cones, embankment behind abutment;flow control works for river/stream, and other protection works It should timely detect and repairthe damage to prevent and mitigate incidents caused by floods

- Check after storm season:

+ Check conditions such as landslides, erosion at abutment/pier foundation which may causeinclination and crack, directly affecting the safety of the works and traffic safety

+ Check flow change compared to previous storm season which may cause the deposition anderosion around bridge abutments and piers

For this type of inspection, it is required the participation of staffs from RM Agency (Department ofTransport, PT); if necessary, staffs from RM Agency (Department of Transport, PT) may directlyoperate this inspection

Inspection results will be main basis to modify the year-end plan; also, as a basis to make plan for eachbridge to monitor, control, carry out RM and repair for next year.

2.3.3 Irregular check:

Conducted by M&R Agency and RM Agency (Department of Transport, PT) or DBVN whenoccurring incidents to bridges/roads or upon the request from superior authorities Upon the check, itshould clearly determine the cause of the damage, assess the damage and take measures for timely andappropriate treatment

With Kcđ <0.8, it should have plan to strengthen the pavement to ensure load capacity of the road

- Check the roughness: Pavement roughness (for all types of asphalt pavement) at running ismeasured by tracking coefficient of the pavement, Kbám, indirectly determined by the average depth

of the sand streak

Kbám = httế /hqđ

Whereas:

httế : The average depth of the sand streak is determined by sand spreading method (test process

to determine pavement roughness in accordance with 22TCN 278-01)

hqđ : The drescribed depth of sand streak, according to test process at 22TCN 278 – 01, is given

in the following table

Average depth

Htb (mm)

Degree ofpavementroughness

Htb > 1.20 Very rough Road passing through difficult and dangerous

terrain (curves with a radius of <150m without

limiting speed, vertical slope> 5%, slope length>100m).

With Kbám < 1: it should enhance pavement roughness by measures such as paving asphalt,paving void AC layer

- Check flatness: Flatness status of pavement determines exploitation quality of pavement structureand operation cost, measured by flatness coefficient of the pavement, Kbp

Kbp = Sgh / Sttế

Whereas:

Sgh :permissible flatness limit corresponding to each type of road pavement

Sttê :actual flatness degree

Sttê : determined by indirect or direct method, depending on the available device of themanagement unit (measurements in accordance with 22TCN 277-01 ‘Standard of checking andevaluating pavement flatness based on flatness index IRI’)

Sgh : each type of pavement (Appendix 2)

With Kbp < 1, it should restore the pavement flatness by paving asphalt or paving a thin layer (forasphalt pavement or CC), or repair the surface (for macadam/aggregate pavement )

With Kbp < 1, but the measured flatness index is at the average level of each type of road surface, itshould repair potholes and make compensation for local concave points

2.3.4.3 For bridge:

After regular inspections, periodic inspections, irregular inspection, in case of detecting complicatedtechnical problems, RM Agency (Department of Transport, PT) shall conduct special inspections.2.3.5 Bridge evaluation:

Bridge evaluation is to assess the condition and the actual load capacity of the bridge, to helpauthorities to take measures to operate the transport and make repair plan

Evaluation stages:

- Initial evaluation: for great bridges using new materials when putting into operation, it shouldconduct evaluation to determine "status 0" of the bridge when as-build documents has not beencompleted

- Next evaluation: After exploitation period of 10 years, the evaluation shall be conducted again;then for every 5-7 years, the evaluation shall be conducted (from the last evaluation)

- Besides, when detecting serious damage which may affect traffic safety and safety of the work, theevaluation shall be conducted immediately

Tasks and requirements of evaluation:

- Assess situation and determine bearing capacity of the bridge; regulation on conditions of transportexploitation

- Evaluate the environment in bridge area which may affect the exploitation

- Propose treatment measures

- Determine the effectiveness after the reinforcement and repair.

Content of evaluation report:

- Name of: bridge, station, highway, location

- General bridge layout

- History and characteristics of bridge exploitation

- Actual technical status of bridge

- Existing issues required clarification

- Conclusions on evaluation results, load bearing capacity of bridge parts (abutments, piers,beams )

- Restoration and repair measures

2.4 Classification and evaluation of technical condition of the construction work

Classify and evaluate technical condition of the construction work in order to make repair plan

2.4.1 For road: Based on damage status of embankment and pavement (potholes, elasticity ),

pavement strength, roughness, flatness to classify For classification criteria, see Appendix 3.

2.4.2 For bridge: Based on inspection results (periodic, irregular, special), evaluation results

management units shall make detailed reports for each bridge as a basis to make repair plan or

2.5.2 Contents of vehicle counting:

2.5.2.1 Vehicle counting station: 2 station types, including main station and sub-station

- Main station: fixed station, no change, used to study vehicle flow, types and vehicle load on a roadsection or an area

- Sub-station: identify local traffic flow on a short road section, narrow area or on road with lowtraffic flow in order to serve the repair or upgradation of the road

2.5.2.2 Principle of station allocation:

- All counting stations should establish a proper network

- The location of the station should present a typical traffic flow of the road section between twointersections Stations should be located at suitable positions to ensure that the collected data shallreflect truly the vehicle flow on that road setion

- On roads of high traffic flow or main roads, it should allocate 1 station per 30-50 km Onsecondary roads or access roads, it will be 1 station per 50-100km

- At ferries, pontoons and toll stations, main station should be placed

2.5.2.3 Time for vehicle counting: 1 time/month in 3 consecutive days at a counting station Vehiclecounting shall be done on dates of 5th, 6th, 7th (for main station) and on 5th, 6th (for sub-station) Forthe first two days: counting in 16/24h (from 5:00 to 21:00); for the 3th day: counting in 24/24h (from0:00 to 24:00) to determine average traffic flow of that month; make arithmetic mean for 12 months tohave average vehicle flow of an entire day per year

2.5.2.4 Counting method: by manual or by machine.

- Manual counting: Counting on both directions of traffic flow on a cross-section of the road

- Counting by machine: follow instructions for each type of machine Vehicle classification of

counting machine should conform to the provisions of Appendix 4 Counting data is stored in the

machine It should regularly maintain the operation counting stations using specialized countingmachine, in which the recorded data shall be transfered to superior authorities

2.5.2.5 Report and data collection:

- On 10th of every month, counting stations shall sent report to M&R Agency

- On 15th of every month, M&R Agency shall synthesize data and report counting results to RMAgency (Department of Transport, PT)

- In 1 year, RM Agency (Department of Transport, PT) shall analyze, synthesize and report data toDRVN on average counting numbers for the first 6 months and annual averages Time to sendreport to DRVN shall be from 20th to 30th of July and in January of the following year

- Report forms of vehicle counting and classification by manual method: see Appendix 4 For

counting may machine, it shall report based on the machine’s program

2.6 Standing duty for traffic assurance

Regulation on prevention and remedy against flood outcomes is stipulated by MOT at Decision2988/2001/QD-BGTVT dated 12 Sept 2001 as follows: Every year, in storm season, in case of havingalarm level 1 or higher, road management agencies shall deploy forces on standing duty to ensuretraffic for 24/24h to quickly handle occurred incidents due to storm and flood

In addition, for great or significant bridges or bridges of complex structure M&R Agency shall carryout bridge guarding for 24/24h (This case shall be specified by competent authorities)

2.8 Registration of bridges, roads

2.8.1 Registration purpose:

The routes when putting into operation shall be under "Registration of bridges and roads" Afterexploitation period of 10-15 years, it is required to register again in order to determine the initialtechnical status and the change of technical factors during extraction

Registration documents includes:

2.8.1.1 Road:

- Diagram of stretch, showing:

+ Geometric elements of the road (horizontal curve radius, Rhorizontal; verticle curve radius, Rvertical;horizontal slope ihorizontal; extreme high slope, iultra high; longitudinal slope, ilongitudinal; embankmentwidth and pavement width - Bembankment, Bpavement; road length, Lpavement), pavement structure (toplayer), thickness of top layer of pavement, pavement strength Ette

+ Dike, retaining wall, overflow protection work, : location, length, tructure

+ Drainage system (culvert, ditch ): location, length, tructure

+ Road signs (posts, signs ), lighting, traffic sign (if any)

- Layout of LCS, ROW, elevation marker (or GPS marker)

- Layout showing figures of encroachment status and violation of road safety corridor.

2.8.1.2 Bridge: registration follows form of "bridge profile ", issued by DRVN in 2002

2.8.2 Registration figures of bridge and road: stored in the computer of M&R Agency, sent to RMAgency (Department of Transport, PT)

2.8.3 Annually, M&R Agency should supplement and update changes in the technical condition ofbridges and roads in registration documents

2.9 Statistics and analysis of traffic accident on road

Directly conducted by M&R Agency

2.9.1 Traffic accidents occurred on roads shall be monitored, synthesized and analized by M&RAgency and Road Traffic Inspectorate in collaboration with traffic police regarding to accident causes,rescue works, congestion clearance damage treatments

Accident minutes should include description of accident site, photos, damage statistics of human andproperty, damage to the traffic work, testimony of witnesses, preliminary review of accident cause.2.9.2 Report regime

- Every month, M&R Agency shall make statistics and synthesize traffic accident, and report to RMAgency (Department of Transport, PT) on the 5th of each month

- In case of serious traffic accident (death or material damage of over 1 billion dong), it shouldimmediately report to RM Agency (Department of Transport, PT) and DRVN

- One in every 6 months, RM Agency (Department of Transport, PT) shall synthesize and report toDRVN

- Accident Report : See Appendix 5.

- Once per year, based on report from M&R Agency, RM Agency (Department of Transport, PT)shall carry out the evaluation on traffic safety at locations where occurred at least 3 accidents orperform the evaluation right after a serious traffic accident occurred

- DRVN, based on the report, shall perfrom reevaluation (if necessary) for highly risky locations andmake treatment plan

2.9.3 The statistics, monitoring and analysis of accidents help authorities determine highly riskylocations (called black points), identify accident causes from view of structural infrastructure (nosignboard, limited visibility, slippery road surface, curve radius on small planning .) to haveadditional treatment plan to ensure traffic safety

2.9.4 Technical measures to restrict and mitigate accidents and ensure traffic safety:

- Upgrade and construct in accordance with technical standards

- Allocate fully traffic safety facilities

CHAPTER III: REGULAR MAINTENANCE

3.1 Embankment

Embankment is required to have appropriate geometric dimensions and good drainage Plants should

be regularly cleared for good visibility and aesthetics

3.1.1 For embankment without slope protection:

Including following contents:

3.1.1.1 Apply additional embankment work:

For narrowed embankment positions where embankment width is sufficient as original design(especially at bridge/culvert approach slabs), or narrowed over 0.3m at one side, it should carry outbackfilling by soil or aggregate with compaction K95 and slope compaction Procedure as follows:

- Mobilize human force to clear trees and grass surrounding the narrowed embankment area.

- Mark grade (width and height of each grade  50cm)

- Fill materials (soil, aggregate as technical standards) into layers ( 20cm thickness), performleveling

- Use compactor Mikasa to compact 5-7 times/point until reaching the required compaction, thenbackfill another layer

- Backfill slopw (sobbing if necessary) and perform finishing work

3.1.1.2 Removval of eroded soil:

Remove eroded soil filled side ditch to ensure slope shape and the initial size of side ditch fordrainage

Note: not to perform leveling to deposit soil at curb, increasing the height of curb, causing standingwater on the road surface

3.1.1.3 Tree trimming and pruning, grass cutting:

Carry out tree trimming and pruning and grass cutting to ensure the vision, the observation of markers,signs, posts and km posts, and drainage On road curb, embankment slope, cut-slope  4m, plants arenot allowed to be higher than 0.2m For slope height > 4m, plants with diameter larger than 5cm withbranch swooped down are not allowed On fill-slope, in range of 1m from road shoulder and the inside

of curve section, plants are not allowed to be higher than 0.2m of road shoulder and not affecting thevision At top of cut-slope, ancient trees should be cut down to prevent falling which may cause trafficcongestion Fallen treen on the road must be quickly removed to ensure traffic

3.1.2 Embankment with reinforced slope: riprap, roof tiling, assemblied concrete slabs ; orembankment having slope of special design (high embankment with counter pressure ranges, stepslope, reinforced embankment by reinforved soil ):

3.1.2.1 Slope reinforced by riprap or masonry with mortar of golden sand and cement, assembliedconcrete slabs

Required works:

- Reconstruct the foot which is eroded and damaged, or supplement riprap

- For lost and broken parts, carry out plaster by mortar of golden sand cement with grade 100, insertriprap into lost positions or replace lost/broken concrete slabs

3.1.2.2 Slope of special design (high embankment with counter pressure ranges, step slope, reinforcedembankment by reinforved soil ) : Beside above mentioned requirements, take notice of:

- Good operation of drainage sysem

- Keep original status of the counter pressure range; make compensation to the lost soil abovecounter pressure range (due to nature, human)

- For reinforced embankment by reinforced soil: follow separate regulation

Curb is required to be smooth, stable, well-drained Range close to the edge of the road surface isrequired not to be uneven, causing standing water at curb or along embankment edge

3.2.1 Unreinforced curb, including following work items:

3.2.1.1 Compensation backfill for curb by stiff granular material:

When eroded curb is 5cm lower than pavement edge, it should carry out compensation backfill by stiffgranular material (not to backfill by soil containing organic matters and other impurities)

Sequence: Cleaning; making roughness to the target area; paving materials and grading to ensuredimentions and horizontal slope degree of 5-6% to the outward; required compaction K95

Work contents include the following:

3.3.1 Dredging: dredge mud and grass inside ditch; no standing water in the ditch which mayundermines embankment and curb

Note: not to deposit at curb, increasing the height of curb, causing standing water on the road surface.

3.3.2 Ditch clearing when raining:

When having heavy rain, it should perform ditch clearing to remove soil, rocks and trees fallen into theditch, causing water runoff onto the sidewalk, along the pavement or overflow causing erosion topavement and slope

3.3.3 Ditch digging

For soil ditch annually deposited by soil, causing standing water inside ditch (especially for line ditch),

it should carry out digging to return initial geometrical dimentions and longitudinal slope of the ditch

to ensure adequate drainage section

Work procudre: before digging, set up stakes to identify ditch edge (straight or curve)

When digging, not to deposit soil at curb, increasing curb height and causing standing water on roadsurface

3.3.4 Repair broken constructed ditch; replace damaged or lost concrete ditch cover:

- Repair damaged part to return the original design

- Insert wedge and mortar to keep balance of concrete cover plates; replace/supplementdamaged/lost concrete cover plates

3.4 Pavement:

At present, there are 5 pavement types in Vietnam:

- Concrete cement pavement

- Asphalt pavement (asphalt concrete, asphalted macadam and bituminous penetration macadam…)

- Macadam pavement

- Aggregate pavement

- Soil pavement

3.4.1 Concrete cement pavement:

3.4.1.1 Repair expansion joint:

During exploitation, inserted materials in expansion joints between the concrete slabs are usuallypeeled out, allowing water to seep down into into foundation, causing shock to running vehicles.Beside, small stones may fall into gap of such damaged joint which should be removed promptly

3.4.1.1.1 Fill into expansion joint: by mastic asphalt mixture.

Notes: Mastic asphalt mixture can be produced by material types with rate: asphalt 60/70: 50%; stone

powder: 35%; Asbestos powder or powder: 15%

3.4.1.1.2 Removal of stones stuck inside expansion joint:

Remove stones stuck inside expansion joint; seal holes by mastic asphalt mixture

3.4.1.2 Repair minor damage (cracked, chipped or broken concrete slabs):

After a period of use, cracked, chipped or broken concrete slabs should be repaired in order to avoidpossible greater destruction

Repair techniques:

- For small and a lot of cracks with crack width  5mm: heated asphalt 60/70 mixed with oil, withratio of 25/75 (oil/asphalt) by weight, at temperature 70-80oC, shall be poured into the cracks, theninsert yellow sand and abrasive grit

- For crack width > 5mm: clean and insert mastic asphalt mixture as 3.4.1.1 above

- For broken/chiped concrete slabs at a small part: Fill the broken/chipped part by mastic asphaltmixture or fine-grained cold asphalt concrete mixture

3.4.2 Asphalt pavement:

3.4.2.1 Cleaning pavement:

Depending on dirtiness of the road, number road cleaning per month shall be arranged, usually about4-8 times/month

3.4.2.2 Prevention against melted surface:

In dry season, surface temperature of the road is up to 60-70oC, causing the emerge of asphalt adhesive

to wheels of running vehicle which can be peeled, causing the damage to road surface

3.4.2.3.1 Patching by oil-asphalt stone mixture, or mixture of hot mix asphalt:

 Asphalt Pavement:

Treatment procedure:

- Use concrete cutters to cut into square shape and dig until the bottom of the pothole

- Remove all discrete materials from patching area; clean the dust to ensure a clean and dry patcharea

- Fill adhesive asphalt (content of 0.5- 0.8kg/m2) to patch area, including the bottom and around theopening; and wait until dry asphalt.

- Fill hot mix asphalt; seal and flatten the patch area; ensure elevation higher than old road surface

by a compression factor of 1.4

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

 Asphalted macadam pavement and bituminous penetration macadam pavement

- Pothole depth of 3 - 6cm:

Treatment procedure:

+ Use mattock and pry to make square shape and dig until the bottom of the pothole

+ Remove all discrete materials; clean the dust to ensure a clean and dry patch area

+ Fill the oil-asphalt stone mixture; seal and flatten the patch area; ensure elevation higher than oldroad surface by a compression factor of 1.4

+ Fill abrasive grit 2-5mm or grit sand or yellow sand to completely cover the stone matrix asphaltfor anti-cohesion purpose with content of 4-5 lit/m2

+ Use vibrator to compact 6-8 times/point or small vibratory roller 0.8T to compact 3-4times/point, speed of 1.5-2km/h

- Pothole depth higher than 6cm:

Treatment procedure:

+ Use mattock and pry to make square shape and dig until the bottom of the pothole

+ Remove all discrete materials; clean the dust to ensure a clean and dry patching area

+ Fill macadam 40/60 or 20/40; flatten; apply compression factor 1.3 so that the macadam layerafter compaction will be 3cm lower than old road surface

+ Use vibrator or vibratory roller 0.8T to compact the macadam

+ Fill oil-asphalt stone mixture with content of 40-50 lit/m2 to seal completely the macadam layer;flatten to keep the elevation of 1cm higher than old road surface

+ Fill abrasive grit 2-5mm or grit sand or yellow sand to completely cover the stone matrix asphaltfor anti-cohesion purpose with content of 4-5 lit/m2

+ Use vibrator to compact 8-10 times/point or small vibratory roller 0.8T to compact 3-4times/point, speed of 1.5-2km/h

Oil-asphalt stone mixture is produced as regulation in 22TCN 21-84 “Production and use of oil-asphaltstone mixture for repairing highway pavement”, issued by MOT under Decision 79/KHKT dated 28Mar 1984

Cold asphalt mix is produced in accordance with regulation in "Technical manual for producing andusing cold asphalt mix for repairing asphalt pavement” issued by DRVN under Decision 439/QĐ-KHCN&QHQT dated 14 Mar 2002

3.4.2.3.2 Patching by hot asphalt:

Only apply for pavement of asphalted macadam or bituminous penetration macadam (significantamount of pothole, big-sized pothole)

- Remove all discrete materials; clean the dust to ensure a clean and dry patch area.

- Fill macadam (40/60 or 20/40) until required elevation with consideration of compression factor1.3

- Use vibrator to compact 8-10 times/point or small vibratory roller 0.8T to compact 3-4 times/point,speed of 1.5-2km/h

- Fill asphalt for 1st time with content of 1.9kg/m2

- Fill macadam 16/20 with content of 18-20 lit/m2

- Compaction by roller 6-8T, 6-8 times/point

- Fill asphalt for 2nd time with content of 1.5kg/m2

- Fill macadam 10/16 with content of 14-16 lit/m2

- Compaction by roller 6-8T, 6-8 times/point

- Fill asphalt for 3rd time with content of 1.1kg/m2

- Fill macadame 5/10 with content of 9-11 lit/m2

- Compaction by roller 6-8T, 4-6 times/point

3.4.2.4 Repair cross-foot crack:

Repair by two hot asphalt layers (22TCN 271-01 ‘Specification for construction and acceptance of theasphalt pavement’), or two layers of cationic emulsified asphalt (According to 22 TCN 250-98

‘Specitication for construction and acceptance of macadam pavement and aggregate asphalt pavementusing cationic emulsified asphalt)

3.4.2.4.1 Two hot asphalt layers, content of 2.7-3.0kg/m2 (depending on the level of crack):

Treatment procedure:

- Cleaning surface by blower (or broom)

- Fill asphalt for 1st time with content of 1.5-1.8kg/m2

- Fill macadam 10/16 with content of 14-16 lit/m2

- Compaction by roller 6-8T, 6-8 times/point

- Fill asphalt for 2nd time with content of 1.2 kg/m2

- Fill macadam 5/10 with content of 10-12 lit/m2

- Compaction by roller 6-8T, 4-6 times/point

- After the construction, it should assign staff to : Guide vehicle to run at speed limit of 20km/h;Control constant travel of vehicles for 15 days; Sweep scatter stones to make compensation forlocal concave points, locations of excessive asphalt but macadam and vice versa

3.4.2.4.2 Two cationic emulsified asphalt layers:

Treatment procedure:

- Cleaning surface by blower (or broom)

- Fill emulsified asphalt for the 1st time; the required emulsion amount depends on macadam sizeand asphalt content of emulsion

- Fill macadam for the 1st time with amount depend on its size; Carry out compaction 1-2times/point by pneumatic roller (or roller 6-8T)

- Fill emulsion for 2nd time

- Fill macadam for the 2nd time

- Compaction by pneumatic roller (or roller 6-8 T), 3-5 times/point.

- After the construction, it should assign staff to : Guide vehicle to run at speed limit of 20km/h;Control constant travel of vehicles for 15 days; Sweep scatter stones to make compensation forlocal concave points, locations of excessive asphalt but macadam and vice versa

Note: Required amount of macadam and cationic emulsified asphalt for spreading 2 layers: See Appendix 6.

3.4.2.5 Repair pavement cracks (cranks only at asphalt concrete layer, not appearing at underneathlayers):

Treatment procedure: 2 ways :

- The first:

+ Widen the crack as wedge form

+ Clean the crack

+ Fill asphalt, emulsified asphalt or hot asphalt into the crack

+ Caulk small-sized hot mix asphalt into the crack

- The second:

+ Widen the crack as wedge form

+ Clean the crack

+ Fill hot asphalt into the crack

+ Fill sand into the crack; 3-5mm lower than orginal road surface

+ Fill asphalt for the 2nd time into the crack

+ Fill sand into the crack; 5-10cm to the outer of crack edge

3.4.2.6 Local concave treatment:

3.4.2.6.1 Asphalted macadam or bituminous penetration macadam

The treatment depends on concave depth

- Concave depth of 3-6cm: Treatment as pothole patching, using asphalt-oil stone mixture or hot mixasphalt (3.4.2.3.1) or patching by hot asphalt ( 3.4.2.3.2)

- Concave depth greater than 6cm: Treatment by macadam, applying standard of three layers of hotasphalt with content of 4.5 kg/m2 (22TCN 271-01 ‘Specification for constructionand acceptance of asphalt pavement)

Treatment procedure:

+ Spread macadam up to the required elevation, considering compression factor of 1.3

+ Compaction to archive 100% requirement of 2nd stage of water bound macadam (22 TCN 06-77

‘Specification for construction and acceptance of water bound macadam); Notice: Not to spray waterand spread sand; requirement of firm compaction and evenness of macadam

+ Spread asphalt for the 1st time with content of 1.9kg/m2

+ Spread macadam 16/20 with content of 18-20 lit/m2

+ Compaction by roller 6-8T, 6-8 times/point

+ Spread asphalt for the 2nd time, content of 1.5kg/m2

+ Spread macadam 10/16, content of 14-16 lit/m2

+ Compaction by roller 6-8T, 6-8 times/point

+ Spread asphalt for the 3rd time, content of 1.1kg/m2

+ Spread macadam 5/10, content of 9-11 lit/m2

+ Compaction by roller 6-8T, 4-6 times/point

3.4.2.6.2 Asphalt concrete pavement:

- Clean targeted location by blower (or broom)

- Make tack coat by hot asphalt (content of 0.5kg/m2) or cationic emulsified asphalt of similarasphalt content

- Spread hot mix asphalt; perform level with elevation higher than original surface based oncompression factor of 1.4

- Compaction by small roller 0.8T, 3-4 times/point, speed of 1.5-2km/h

3.4.2.7 Repair flaked asphalt pavement:

Repair by 2 layers of hot asphalt, content of 2.7-3.0kg/m2 (depending on the degree of surfaceflaking); the same as outlined in Section

3.4.2.4.1

3.4.2.8 Repair worn asphalt surface:

Asphalt pavement after a long using time will be gradually worn, revealing the stone Treatment asfollows:

3.4.2.8.1 Traffic flow under 150 vehicles/day & night:

Apply 1 layer of hot asphalt (22TCN 271-01 ‘Specification for construction and acceptance of asphaltpavement)

Treatment procedure :

- Clean targetd area by blower (or broom)

- Spread asphalt, content of 1.5kg/m2

- Spread macadame 10/16, content of 15-17 lit/m2

- Compaction by roller 6-8 T, 4-6 times/point

3.4.2.8.2 Traffic flow from 150 vehicles/day & night:

Apply 2 layers of hot asphalt with content of 2.7-3.0kg/m2 (depending on damage degree of pavement)

as 3.4.2.4.1 ; or 2 layers of cationic emulsified asphalt as 3.4.2.4.2

3.4.2.9 Treatment for pavement under elasticity and local subsidence:

Pavement under elasticity and local subsidence: pavement foundation structure is partially orcompletely damaged; sometimes, soil is emerged from pavemeent

In case of wet area or rainy season, it can use sand (coarse sand is the best) for replacement

- For subbase, stone waste can be used (cohesive soil content < 6%), divided into layers  20cm forcompaction

- Return base course and surface layer as original structure.

3.4.3 Macadam pavement:

3.4.3.1 Compensation of grit sand for pavement:

Due to vehicle running, small-sized rocks will be casted to road edge and smashed into powder Itshould frequently compensate small-sized granular materials (grit sand)

3.4.3.2 Pothole patching:

Macadam of appropriate sizes (depending on pothole depth) should be used for patching

Treatment procedure:

- Make clean cuts along the sides of prospective patch area; make depth at least 10cm

- Blow water and debris from the pothole

- Spread macadam 40/60 or 20/40; perform leveling based on compression factor of 1.3

- Compaction by vibrator or vibratory roller 0.8T

- Spread macadam 10/20

- Compaction by vibrator or vibratory roller 0.8T

- Spread material, macadam 5/10 and abrasive grit 2/5mm or clean grit sand or yellow sand; Fill sized granular material firstly, then small-sized granular material; perform watering during fillingmaterials; use broom to insert materials into gaps

big Compaction by vibrator, 8-10 times/point; or small vibratory roller 0.8T, 3-4 times/point, speed of1.5-2km/h

3.4.4 Aggregate pavement and soil pavement:

3.4.4.1 Compenate grit sand for pavement: As 3.4.3.1

3.4.4.2 Watering for dust prevention:

To mitigate dust emission due to running vehicles in resident area, on dry days, it should performwatering at least 1 time/day depending on weather condition

3.4.4.3 Slough prevention:

- Remove the slough

- Spread aggregate or brick debris or stone waste into boggy location

- Perform rolling by roller 6-8T

- Clear drainage ditch

3.4.4.4 Repair corrugated road surface:

- Perform leveling at corrugated location For a lot and continuous corrugation, surface layer should

be scarified

- Use grader to return superelevation, cross fall and flatness to pavement

- Perform rolling by roller 8-10T

3.4.4.5 Pothole and local concave repair:

- Make clean cuts along the sides of prospective patch area with the depth at least the depth of thedamaged point

- Perform watering (for extreme dry case)

- Spread aggregate and perform leveling (compression factor 1.3)

- Use vibrator or vibratory 0.8T for compaction; perform watering to optimize the moisture whenrolling if necessary.

3.4.4.6 Elasticity and subsidence treatment:

- Excavate for elastic location until hard soil and perform compaction to to ensure K95

- Use foundation soi as technical standards or sand, lime furnace slag, broken bricks ; devide intolayer  20cm and perform compaction K95

- Spread aggregate of surface course: thickness of 10 - 20cm; compaction K95; satisfied cross fall

3.5 Retaining wall

Retaining wall is a structure type used to prevent landslide, ensuring embankment stability Contentsinclude the following items:

3.5.1 Retaining wall by riprap and gabion:

- Perform plant clearing

- Replace lost rubble and broken steel wire

- Clear channel to prevent the flow to area of retaining wall

- Regularly perform checking and monitoring of the deformation of retaining wall

- Cover cracks and broken points by yellow sand cement class 100 (if any)

3.5.2 Retaining wall by cement concrete and masonry rubble:

- Perform reinforcement and repair for the damage of retaining wall

- Cover cracks and broken points by yellow sand cement class 100 (if any)

- Rebuild broken points by rubble masonry with the use of yellow sand cement mortar class 100 (orcement concrete class 200)

- Perfrom plant clearing

- Regularly perfrom checking and monitoring

3.6 Spillway and underground road way:

Content includes:

3.6.1 Cover cracks by yello sand cement class 100; rebuild broken positions by rubble masonry withthe use of yellow sand cement mortar class 100 on the slope

3.6.2 Replace or fix cement concrete slabs to ensure flatness

3.6.3 Paint water column, marker posts and signboards for convenient level observation

3.6.4 Repair/replace broken/lost marker posts and signboards

3.6.5 Perfrom clearing inside culvert (rocks, twigs, mud and garbage) and at upstream anddownstream

3.6.6 Supplement rubble to reinforcement foot of the slope

3.6.7 Supplement rubble after every time of submerge (for construction works of rip rap)

3.7 Tunnel

Tunnel is a collective and modern traffic works, including a series of construction works such as traffictunnel, ventilation tunnel, emergency exit , which are arranged of traffic facilities such as lightingsystem, communication system, ventilation and drainage systems

3.7.1 Conventional tunnel:

Include following contents:

3.7.1.1 Tunnel lining

- For tunnel lining of natural stone, it should regularly check In case of finding broken/weatheredpositions or water leakage from the top, it should carry out inspection and repair plan

- Tunnel lining of concrete, reinforced concrete, maonry stone:

+ Regularly check In case of detecting crack, it should be marked by plaster or sand cementmortar to track and report to the superior

+ In case of detecting water leakage from the top, it should carry out study to find out causes,check drainage system at the top for immediate repair, report to the superior and propose treatment.+ For minor damage of concrete and stone masonry positions: It should carry out repair to restororiginal state, ensuring aesthetics

3.7.1.2 Drainage system:

Drainage system in the tunnel includes side ditch, line ditch, buried ditch Contents as follows:

- Perform plant clearing, dredging inside ditch and manhole to ensure good drainage operation

- For buried ditch, in case of detecting poor drainage operation, it should consider causes and timelyrepair

- Repair damaged parts concrete and stone masonry Replace damaged cover plates of side ditch toensure safety for pedestrians Replace rusted/damaged water pipes not ensuring the operation.3.7.1.3 Maintenance and repair of lighting system:

Lighting system includes light bulbs, lampshades, light poles, wires, electrical panel, circuit breakers,generators, transformers,

- Light bulb: Immediately replace failed light bulbs, ensuring well-operated bulb rate  90%

- Rusted light poles and lampshades should be repainted (1 time/3-5 years) In case of damage,replacement should be carried out immediately

- Electrical equipment such as generators (substation), switch, wire, electric cabinet must be undermaintenance and repair as regulation of power sector

3.7.2 Mordern tunnel:

Maitenance and repair for this tunnel type shall apply specified regulation

3.8 Road down to ferry

Maintenance and repair shall be the same to other similar pavement types

It should timely repair damaged section at ferry terminal (dock) due to erosion or shock force fromvehicles

3.9 Escape ramp:

Contents as follows:

3.9.1 Repaint or replace the damaged reflective cover on signboards for clear observation of driver.3.9.2 Clear obstacles (soil, fallen rock ) on escape ramp, especially the transition section betweenmain road and escape ramp

3.9.3 Clear drainage dithc

3.9.4 Supplement sufficiently sand, stone and gravel on the escape ramp

3.9.5 Scarify surface of escape ramp (especially after each rain, sand layer of pavement is usuallycompacted) to ensure sufficient friction as original design

3.10 Drainage culvert

Culvert types are classified by shape (pipe culvert, slab culvert, box culvert, arch culvert ), built byreinforced concrete or stone masonry Culvert structure includes 3 main parts: body, inlet and outlet(including energy dissipators of culvert)

Contents as follows:

3.10.1 Culvert clearance:

Perform dredging of deposited soil and rock in manholes at upstream, inside culvert and downstreamfor drainage clearance

3.10.2 Minor repairs by yellow sand cement mortar class100:

- Use yellow sand cement mortar class 100 to repair the damage and crack of culvert joints, top wall,side wall, apron, culvert lining built by masonry stone

- For damaged structure of masonry or cement concrete: Apply cement mortar masonry class 100 orcement concrete class 100 to rebuilt as original stage

3.10.3 Channel flow clearance at upstream and dowstream:

Contents as follows:

- Dredge deposited soil and sand

- Perform plant clearance at two sides of channel and culvert opening for good drainage operation.3.10.4 Whitewashing for culvert’s headwall:

Apply 2 whitewash layers to headwall (4 times/year)

- Clean bridge desk and drainage system on bridge desk; replace damaged water drainage pipes

- Pain bridge handrail, 1 time/2-3 years

- Whitewashing for bride handrail; 1 times/year

- Maintenance for bridge lighting system (if any)

- Minor repair sidewalk on bridge (if any)

- Minor repair for bridge desk

Depending on each type of bride desk structure::

+ Asphalt concrete: Pothole patching (if any) as asphalt concrete pavement

+ Cement concrete:

Minor repairs as cement concrete pavement

Repair of expansion joints between concrete slabs

Replacement of broken slabs, fix the stability

+ Wooden bridge desk:

Replacement of all broken/rot wooden components

Fix/ bolts of bridge desk slabs for stability

3.11.2 Expansion joint:

- Expansion joint between two beams should ensure their common movement

- Remove hard objects fallen into expansion joints

- Apply measures to prevent expansion joints from runoff water on bridge desk

- Regularly perfrom cleaning

- Regularly tighten bolts of expansion joint and beam; supplement plugs (for rubber expansionjoint); handle deformed steel slabs (for steel expansion joint)

3.11.3 Bridge beam:

- Reinforced Concrete Structure; Prestressed Reinforced Concrete Structure:

+ Locations where concrete surface of the beams are under aging or mold due to water infiltration

or environmental impact: Perform cleaning and cover with waterproof agent or cement mortar toprotect

+ Reinforced concrete beams having cracks beyond the allowable limit of 0.2    0.3mm:Cover with cement mortar For bigger cracks, it should apply specified treatment and mark byplaster or cement mortar to monitor

+ Locations of damaged and deformed concrete: Perform cleaning and restore the original state.+ Locations whre rebar are exposed and rusted: Remove rust and restore the original cover SIKA

or EPOXY mixed with cement (mixing rate specified by manufacturer) are used to repair

+ Cracks of prestress reinforced concrete beams: Mark by plaster or cement mortar to monitor

- Steel platform, composite steel and concrete structure:

+ Regularly perfrom cleaning at beam ends (especially edge beams) where impurities are easilyfallen into, causing rust

+ At joints of beams and platforms (especially bottom beam): Ensure cleaniness and ventilation;Absolutely not to allow water kept at these joints

+ Locations where paint is scratched due to collision: Immediately repaint by rust inhibitive pain (2layers), then apply a coating layer

+ Locations under local rusting: Remove rust (can use scratching brush) then perfrom painting asabove mention

+ Fix loosen bolts; replace damaged bolts and rivets by similar types

+ Nếu các tấm bản BTCT kê trên dầm thép bị "cập kênh" thì phải dùng nêm bằng cao su chèn chặt(Nếu cấm được xe thì dùng vữa SIKA hoặc keo EPOXY bơm vào)

+ Unstability of reinforced concrete slab on steel beams: Insert rubber wedge (In case ofprohibition, it can use SIKA or EPOXY)

3.11.4 Bridge bearing:

2 types: Steel and rubber Work contents as follows:

- Perform cleaning for bearings

- Lubrication for bearings (for steel type): 1 time/year

3.11.5 Bridge abutment, pier:

- Perform cleaning for coping of abutment, pier

- Cover local cracked/broken masonry positions of abutment, pier and quarter corner: By cementclass 100

- Perform plant clearing at abutment wall, quarter corner and 20m in range of bridge upstream anddownstream.

- Clear flow under the bridge, remove stuck strees from abutment and pier

- Sửa chữa bậc lên xuống cầu và sơn chống rỉ các thang kiểm tra cầu (nếu có)

- Repair bridge steps and apply rust inhibitive paint for checking bar (if any)

3.11.6 Bridge approach slab:

- Repair pavement of bridge approach slab

- Perform plant clearing on slope of bridge approach slab (10m from parapet wall for each side)

- Repair and supplement broken/deformed/lost signboards, MLG, elevation markers and parapet atapproach slabs

- Repaint unclear signboards: 1 time/2-3 years

- Backfill deformed embankment of bridge approach slabs

3.11.7 Flow diversion dike, protective structures:

- Perform patching for cracks and local broken mortar joints of flow diversion dike by cementmortar class 100

- Perform plant clearing around flow diversion dike and protective structure

Note: For suspension bridge, apply specified regulation for maintenance and repair

3.12 Construction works for management:

Construction works for management include: Road Management Centre of QL&SCĐB and theCounty’s QLĐB; Bridge Guard Station; Counting Station; Toll Station, Weight Station

Maintenance and Repair for these construction works include:

- Maintenance and Repair for construction works (buildings): Follow maintenance guide at Circular

No 05/2001/TT-BXD dated 30 August 2001

- Maintenance and Repair for facilities serving the maintenance and repair: Follow themanufacturer’s guidance

3.13 Road traffic signs

According to 22 TCN 237-01 for Road Traffic Signs issued by MOT at Decision No BGTVT dated 20 Dec 2001, “road traffic signs include signs for signaling, guidance, command " formotor vehicles, non-motorized vehicles and pedestrians on road to ensure traffic order and safety.Maintenance and Repair requirements: Road traffic signs should be always bright and clean with clearsymbols as original design

4393/2001/QD-3.13.1 Traffic signboard:

Include following items:

- Painting (column and the back of signboard): 1 time/2-3 years

- Painting and replacement of damaged reflective layer on signboard

- Replacement of broken/lost signboard

- Repair for deformed signboards; fix bent/tilted signboards; clean signboard surface

- Plant trimming and clearance of obstacles preventing signboard observation

3.13.2 Road marking: