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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

DESCRIPTION OF
DETAILED CONSTRUCTION PLAN
CONSTRUCTION ITEM:
IMPROVEMENT OF LY BRIDGE, KM225+170
of Construction Package - CP2

PROJECT:

IMPROVE AND UPGRADE YEN VIEN – LAO CAI RAILWAY

PART 1. BASIS OF THE CONSTRUCTION PLAN.
PART 2. CHARACTERISTICS OF THE CONSTRUCTION WORK.
PART 3. GENERAL METHOD OF CONSTRUCTION
PART 4. DETAILED METHOD OF CONSTRUCTION.
PART 5. CONTRACT PACKAGE IMPLEMENTATION SCHEDULE
PART 6. CONCLUSION.

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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

PART 1
BASIS OF THE CONSTRUCTION PLAN

Basis:
- Pursuant to the Decision No. 2742/Q§-BGTVT of Ministry of

Tranport dated September 10 2007 on approving the project: Yen
Vien – Lao Cai Railway Upgrading Project under Kun Ming – Hai
Phong transport corridor in which including Ly Bridge, section
Km225+170.
- Pursuant to bid documents of CP2 package: Improve, upgrade Yen Vien - Lao Cai
railway.
- Pursuant to the approved Shop Drawing designed by Construction Joint Stock.
- Pursuant to Subcontractor Contract No. NKSP-VN-CP2-017 dated 02/04/2012
between Namkwang - Sampyo JVC and Road and Bridge Engineering and Mechanical
JSC.
- Pursuant to the competence and experience of Bridge Engineering and Mechanical
JSC.
- Pursuant to applicable procedures, standards on construction, and the fact of
construction site
Hereafter shall be the complete and detailed construction plan provided by Bridge
Engineering and Mechanical JSC.

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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

PART 2
CHARACTERISTICS OF THE CONSTRUCTION WORK

I. VỊ LOCATION, PURPOSE AND IMPROVEMENT REQUEST, SIZE OF LY
BRIDGE:
1.1 Location, purpose and improvement request, size:
1.1.1 Location:

- Ly Bridge is located in Yen Vien – Lao Cai Railway in Lang Thip Commune, Van
Yen District, Yen Bai Province. Actual chainage of this bridge is Km224+813.93.
1.1.2 Purpose and improvement request:
- Purpose: Upgrading the existing bridge of Sung which is downgraded
- Request: Assure the training operation and drainage.
1.1.3 Construction items:
- Repair 2 existing abutment.
- Replace existing girder by new composite girder, using concrete sleeper with
ballasted.
- Adjust longitudinal section, reinforce slope, cone and bridge approach.
1.2 Location, altitude:
- Based on the location of Yen Vien - Lao Cai railway
- Coordinates, benchmarks: making use of national coordinate system
II. CURRENT SITUATION:
2.1. Characteristic of plan and longitudinal section:
- Ly Bridge is located in Yen Vien – Lao Cai Railway in Lang Thip Commune, Van
Yen District, Yen Bai Province
- The bridge is on straight and flat alignment.
2.2. Geological characteristic:
- From elevation 64.15 – 59.65m: Masonry, its hardness is IV-VI class, TCR=20%.
Rnk = 90 Kg/cm2.

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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

- From 59.45 – 56.85m: G¬ nai rocks weathered by wind and water,gray brown, gray
yellow its hardness is IV.

- From 56.85 – 54.75m: G¬ nai rocks weathered by wind and water, break the same
Macadam, gray brown, its hardness is VI.
2.3 Hydrological characteristic:
- The highest flood in 1971: 72.93m
- The second highest flood in 2008: 66.09m
- The third highest flood in 1986: 64.52m
- The Hydrological calculation for Ly bridge
+ Q1% = 223.40m3/s
+ V1% = 2.39m/s
+ H1% = 71.34m
+ L cần thiết = 14.50m
2.4. Current characteristic:
- Existing girder is double steel I-profile 170x545x15mm.
- Drainage width Lo = 15.88m.
- Load weight: 4.2T/m.
- Telecom-cable is placed on bridge, attached to the girder.
2.5. Applicable Technical Specifications:
- The bridge is designed for single rail gauge 1000mm
- Designed load weight T14 for all of the abutment and beam.
- Designed rate: H=1%.
- The upper structure uses rail P50
2.6. Applicable regulations:
- Regulations on Technical design of rail gauge 1000mm enclosed with the Decision
No. 435/QĐ-KT4 dated 09 February 1976 of Ministry of Transport.
- Standard 22TCN18-79 of the Minstry of Transport on Culvert Design.
- Technical Specification No. 22TCN340-05 on Railway exploitation enclosed with the
Decision No.76/2005 QD-BGTVT dated 30 December 2005 of the Minstry of
Transport.
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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

- Specifications of repair of railway infrustructure enclosed with the Decision 173/QDGTVT dated 25 February 2000 of the Minister of Minstry of Transport.
- Standard 22TCN 171-87- Specifications for Geological Survey and Design of
Roadbed Stabilization in area with slippage and erosion.
- Standard 22TCN 342-05/2006 enclosed with the Decision 75/2005/QD-BGTVT
dated 30 December 2006 of the Minstry of Transport.
- Other related regulations.
III. CONTENT OF DESIGN:
3.1 . Abutment:
-

Repair 2 abutments, including abutment head, padstone, retaining wall, sidewalk
with concrete and reinforcement.

-

The grade of concrete for abutment is 250, padstone grade is 300

-

Reinforced bar types are CI, CII.

3.2 . Span structure:
Replace the existing span structure with reinforced concrete beam below ballast
aqueduct, pre-stressed concrete sleeper.
Basic dimension as below:
-

Caculated length

Lp = 16.80m

-

Total length

L = 17.50m

-

Main Girder height

H = 1.472m

-

Beam structure height

H = 1.015m

-

Gap of center-to-center of 2 girders B = 4.60m

-

Supporting height

-

Types of reinforcement are CI, CII.

H = 0.158m

3.3. Bridge approach and other tasks:
- Adjust the longtitudinal section along the bridge according to longgitudinal section
document, repair slope behind at ends of abutments and keep the cone intact.
- Build bew cut-off dike, ruler, slope protection of bridge approach with ashlar and
mortar within the area of 25 meters behind Yen Vien and Lao Cai abutments.

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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

PART 3
GENERAL METHOD OF CONSTRUCTION

I. OBJECTIVES
- Complete the constrution work within the schedule and in accordance with the
requirements of bidding documents.
- Assure the conformance of the construction work with quality and technical
requirements, procedures, norms and standards as designed.
- Assure the absolute safety in operating train and environmental hygiene; reduce the
impact on daily life of the resident during construction.
- Assure the absolute safety for human and machinery during construction.

II. DIVISION OF CONSTRUCTION SEGMENT:
- Based on the actual construction quantity of Ly bridge.
- Based on the capacity and experiences of the Main Contractor and Sub-contractors
involved in the awarded joint venture who have been approve by the Employer.
We, the Contractor, shall mobilize a construction team to complete all items of
Thuy Loi Bridge Improvement as following:
+ Bridge items.
+ Supperstructure.
+ Bridge approach
III. PERSONNEL ASSIGNMENT:
1. Organising the construction site:
* The Board of Management Unit consists of:
- Project manager: Being responsible for managing all activities on the site, being the
legal representative to resolve any problem relating to the project.
- Members of the board: Being assigned by the board of management and responsible
for their assigned tasks, including:
+ Chief leader of the site shall make a detailed construction plan according to the
progress, directly manage the manufacturing and constructing process at the site. He/She

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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

shall take responsibilities in front of the manager for the construction progress, quality
and labour safety.
+ Technical leader shall directly manage the construction work, work on behalf of
the chief leader in case of his/her absence. He/She shall take responsibility in front of
the Chief leader for all construction operations at the site. Based on the detailed

construction plan which has been approved, the technical leader shall assign daily
manufacturing tasks to corresponding teams. He/She shall check and speed up all
specialized operations and functions of each team as assigned, coordinate with off-site
teams to solve any procedures relating to the site.
+ Progress management team: this team has a progress manager who is in charge of
checking the progress, speeding up and reminding construction teams, and making
immediate report to the Chief leader or the Technical leader in case of delay or standstill.
+ Technical management team: Shall follow up the construction teams, work and
monitor directly the construction process to ensure the compliance with approved design
document. Everyday, technical engineers are responsible for monitoring the work,
logging job record for all construction items so as to create a basis for the payment and
as-built document.
+ Finance and accounting team includes:
Accountant, finance staff: Shall be responsible for any payment and settlement of
the construction work.
Administrative staff: Shall be responsible for checking, monitoring labour
protection at the site, communicating knowledge of labour safety and empowering the
labourer working at the site with protective measures, such as protective clothes, shoes,
helmets, etc.
+ Quality management team includes:
Technical management and construction supervision team: shall be responsible for
checking, monitoring the construction process in accordance with the approved design
document and as-built drawing; monitoring the operation safety and labour safety of all
manufacturing units to ensure the compliance of construction work with approved
design document; strictly following all procedures and standards during execution. After
completing each construction item, the contractor itself shall conduct an acceptance
inspection and document any existing problem. After fixing such problems, the
Supervisor shall be invited to take acceptance test for the item.
Material management team: Shall be responsible for delivery of materials to the
site in a timely manner and following the schedule. In addition, the material

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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

management team shall be responsible for storing, maintaining and monitoring the
quality of materials as in approved specifications.
+ Equipment management team: Shall be directly responsible for the safety of
machinery and equipments; Must ensure that such machinery and equipments shall be
supplied sufficiently and timely for execution; Must quickly repair and fix any problem
relating to machinery and equipments.
+ Safety management team: Because the construction is executed on running
railway, the contractor must pay special attention to the safety of operation. The staff in
charge of safety shall be responsible for communicating all knowledge relating to the
safety of operation, essential procedures and standards for each construction team.
Everyday, the staff in charge of operation safety and labour safety shall be responsible
for checking safety assurance procedure at the construction site.
+ Security management team: Shall be responsible for ensuring security at the site,
checking and guarding all kinds of materials, machinery and equipments available at the
site. The security of each construction team is assigned to 2-3 personnel who are also in
charge of the security for the whole construction work.
+ Environmental management team: Shall be responsible for communicating
knowledge of environmental hygiene, checking and monitoring the implementation of
hygiene and environment protection at the site.
+ Fire and explosion prevention and protection team: Shall be responsible for
communicating knowledge of fire and explosion prevention and protection, ensuring
safety for the construction work without fire and explosion.
+ Construction teams: Including multiple construction units which shall execute

each separate construction item or on different location. Each construction unit shall be
managed by one leader who has skills and experiences.

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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

2. Arranging personnel to execute construction items of Ly bridge
- Based on the construction volume, we shall arrange suitable personnel, machinery and
equipments to ensure the whole progress of the construction package and of each stage
(within the scope of execution) with one construction team. The total number of
workers to mobilize at each specific time and for each specific requirement during
construction is 30 people:
- The estimated time for completing this construction package is within 90 days, from
the effective date of contract to the handing-over date. During such time, the personnel
must be arranged properly to execute multiple construction items at the same time.

LIST OF KEY ENGINEERS INVOLVED IN CONSTRUCTION SITE

NUMBER OF WORKERS INVOLVED IN CONSTRUCTION

N
o.

Name

Position

1

Le Quang Duy

Genaral
operating

2

Trinh Van Toan

Technical staf

3

Duong Vinh Thiep

Technical staf

4

Pham Duc Thanh

Foreman

5

Le Dang Kim

Notes

Safety

Number
of
workers

Grade 1/7 to grade 3/7

Grade 4/7 to grade
7/7

Provider

30

10

20

Contractor

Total of workers involved in construction are 30 workers.

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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

III. THE CONTENT OF GENERAL CONSTRUCTION PLAN:
The whole construction work shall be executed by manual work and machinery. In
order to ensure the absolute safety for construction and reduce impact on the station
operation, the construction unit must conduct their work properly and neatly; all
materials, machinery and equipments must be gathered outside the railway restricted
area to eliminate any impact on train operation. Wasted soil must be gathered and
transported to specified location for dumping.
Construction steps are as followings:
1. Preparation:
- Prepare workers’ hut and housing
- Prepare human resource, construction machinery and equipments.
- Survey of Shop drawing and preparation for construction procedures.
- Construction of the temporary pier, beam for banding rail, steel bars
2. Construction:
- A construction team shall be mobilized for these following items:
+ Repair abutment head.
+ Contruct bridge approach
+ Contruct supperstructure
+ Construct cut-off dike, slope and cone of 2 abutments.
3. Completion, Check, Acceptance and Hand-over:
Resolve the problems, clean the construction site. Hand over the old materials to the
Management Unit. Complete the required necessary formalities in order to check and
accept and bring into service.

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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

PART 4
DETAILED METHOD OF CONSTRUCTION
I. MATERIALS SUPPLY AND TECHNICAL REQUIREMENTS.
1. General requirements:
- All of the utilized materials will satisfied current Vietnamese Standards (TCVN) and
the current standards (TCN).
- The utilized materials will have quality certificate of producers and test result from
certified laboratories.
- The utilized material will meet the requirement of quality from the approved design
documents, have origin certificate, other legal parameters and be approved by the
Employer.
- Prior to be utilized, the concrete components will be examined in certified laboratory
to find the suitable mix method for them so that the quality of concrete will be
controlled.
Particular materials as follows:
1.1. Rail and rail fastening accessories
1.1.1 Rail:
- Rails will have all of the required minute of acceptance prior to be utilized.
- The utilized rail is P50, L=25m, new and approved by the Employer.
1.1.2. Rail fastening accessories:
- Type: Fish plate P50 + bolts
- All of the accessories meet the technical requirements.
- Rails provided by the supplier have to be approved by the Employer and Supervision
Consultants.
- The accessories are gathered at construction site as soon as the work is implemented
and placed in storage.
1.2. Sleeper and fastening accessories for rail and sleeper
1.2.1. Prestressed concrete sleeper:

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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

- Supply method:
Prestressed concrete sleeper will be supplied by the Construction Material FactoryConstruction Joint Stock Company No.6, then be transported by train to the track
section and then being unloaded to the rendezvous in the worksite.
- Types of sleepers: Prestressed concrete sleeper gauge 1000mm – Flexible
Accessories Pandrol - Rail P50.
1.2.2. Fastening accessories for rail and sleeper:
Pandrol flexible accessory pack for a prestressed concrete sleeper:
- The utilized flexible accessory will have the quality certificate of the manufacturers,
test certificate from certified laboratory and the quality inspection meet requirements
of the project and approved by the Employer and Supervision Consultant.
+ Rail clip:

4 units

+ Insulating plate:

4 units

+ rail rubber base:

2 units

+ cast shoulder :

4 units (installed when casting sleeper)

- Types: Pandrol flexible accessory for prestressed concrete sleeper tied with rail P50
1.3. Sand:
- Check the sand: the utilized sand has durable particles, firm and clean and does not
have the amount of impurities over the accepted amount in the Standard No.
TCXDVN7570-2006 Aggregate for concrete and mortar- technical requirements and
laboratory test will comply with the Standard No. TCVN7572-2006 - Aggregate for
concrete and mortar – Test methods.
- Supply: sand will be bought locally and transported to the work site by trucks.
- Type: yellow sand.
1.4. Stones:
1.4.1. Ballast:
- Check construction materials: the specification of ballasts will comply with the
Document No.1037 CV/CSHT dated 25/6/2001 of Vietnam Railway.
+ Firm, durable, homogeneous, free of cracks.
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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

+ Dimension 2,5cm x 5cm,

clean

and

meet

requirement

of

intensity,

compaction intensity ≥ 800 kg/cm2.
+ Shape and pureness: the stones will have their lengths be 3 times bigger than
their widths or thickness and occupy less than 15% of the total weight.
+ Number of stones which are bigger than 50mm or smaller than 25mm will
less than 5% of the total quantity
+ The crushed stones will have to be clean, free of soil and other impurities. In
case the stones have clay, the amount of clay will less than 0,5%.
+ The stones’ hardness will not smaller than 50 if the are examined by the
“PM” hardness tester.
+ The hygroscopicity/water-absorption of the stones which are steeped in water
for 48h will not be over 1,5% in term of weight.
- Supply: Stones are bought locally, have qualified amount and quality, and transported
to the work site by trucks or train.
- Type: ballast for railway.
1.4.2. Crushed stones for mixing concrete:
- Check the materials: the utilized crushed stones will meet requirements of dimension
and granularity and be clean and comply with the Standard TCXDVN7570-2006 and
Standard TCVN7572-2006.
- Supply: Stones are bought locally, have qualified amount and quality, and transported
to the work site by trucks or train.
- Type: crushed stones 1x2, 4x6 for concrete.
1.4.3. Ashlar:
- Material examination:
+ The utilized ashlars shall be clean, solid and durable, homogeneous, free of cracks
have the minimum strength of 400kg/cm2.

+ The shape and dimensions of ashlars shall be showed in drawings, otherwise they
shall have volume not smaller than 0,01m3, the shortest side not less than 15 cm but
not bigger than the thickness of the structure. Each ashlar shall not be either concave
or convex or have dust.

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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

-

-

+ Ashlars shall be repaired in order to get rid of weak parts. Ashlars shall be cut and
dressed so that they shall be thin and the junction lines shall have baseline offset not
bigger than 20mm. The radius of the curve at the corners of the ashlars shall not longer
than 30mm.
Supply: Stones are bought locally, have qualified amount and quality, and transported
to the work site by trucks or trains.
Type: ashlar.
1.5. Cement:
Material examination:
+ The utilized cement shall achieve the standards TCVN 6260:1997.
+ Cement shall have the origin certificate and be examined for quality.
+ In case the cement has been kept for more than 3 months, we shall examine and
ask for approval for it from consultants and supervisors.
+ Any cement which has the compressive strength of the standard cement mortar in
28 days not smaller than its grade shall be accepted.

+ In case there shall be samples of cement at a factory or work site do not pass the
requirements, we shall replace the whole batch of the unqualified cements by batch
of qualified cement.
+ Cement shall be placed 20 cm from floor, storage shall have roof.Cement quality
shall be examined.
Supply: cement are bought locally, have qualified amount and quality, and transported
to the work site by trucks or trains.
Type: cement PC30, PC40, PCB30, PCB40.
1.6.
Water:
Material examination: water shall be clean, have no impurities and follow standard
TCXDVN 302-2004.
Supply: well.
Type: water for construction
1.7. Other materials:
Other materials shall be bought from local certified companies.
II. HUMAN RESOURCES, CONSTRUCTION MACHINES
1. Work site management committee
- Number of conductors: Based on the actual situation, the numbers of conductors will
be 2 – 3 people.

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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

- Construction experience required: involving in railway and road construction for
recent 10 years.
2. Workers:

- Based on the work amount, we shall assign human resource, machines for construction
which is suitable for the project and construction processes ( in construction scope)
into 1 teams. The number of workers is 30 people.
- For each team, we shall assign experienced team leader, workers in order to guarantee
the construction of Ly Bridge shall meet the required quality and progress.
- The total estimated time for the project is 88 days, from the effective day of contract to
the transfer of work. During that time, workers shall be assigned to construct multi
work items.
3. Construction machines:
Construction equipment and machines shall be mobilized to construct all of the items
of the project:
Construction equipment

Quantity

Capacity

Functions

Compressor AIRMAN

1

7.5m3/p

Drilling

steel cutting KAWA

1

Welding machine DENZO

1

250A

Welding

Concrete mixer HD-750

1

750L

Concrete mixing

Concrete mixer

1

350L

Concrete mixing

Needle vibrator MIKASA

2

1.5KW

Ramming

Concrete hammer TCB-200

3

7.5Kg/cm2

Concrete cutting

Excavator KOMASU

1

0,6m3

Soil excavation

Truck

1

10- 15T

Transportation

Rammer MIKASA

1

2KW

Hydraulic jack MASADA

6

50T

Jacking

Chain-Palang K II - 5T

2

5T

Pulling and braking

Tirfor SUPER TILL S-35

5

5T

Pulling

Bearing puller ENERPAC

4

30T

beam placement

Cutting

ramming

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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

Hand-saw TQ NQG-3

1

2KW

Rail sawing

Rail Driller TQ 220 vol

1

2KW

rail hole drilling

Generator

1

Power generation

Surveyor level, theodolite

1

Measurement

Track jack

2

Lifting the track

Other equipmet

1 set

III.TECHINICAL MEASURES FOR MAIN TASKS
1. Measure for electricity supply, water supply, drainage, traffic, communication
in the construction.
* Electricity supply measure: contractor shall contact local electricity company for
electricity supply. Besides, electricity powers shall also be supplied...
* Water supply measure: contractor shall contact local residents for excavating wells
* Drainage measure:

- Drainage for foundation construction: during the construction process, water shall be
drained by slope of the road.
- Drainage for channel construction:
+ make slope for drainage water during channel construction.
+ All of the unused soils and stones shall be moved.
* Traffic measures:
There shall be personnel who observe the construction at the railway.
* Communication measure
- For each construction team, there shall be phones, besides each person in the work
site shall have hand phone.
- During construction, communication and optical cable shall be protected.
2. Organize work site, temporary structures, construction machines, storages and
yards
2.1 Organize work site:
In order to facilitate the construction, we shall make camps at Van Phu station. In
order to assure the safety of workers, steel B40 fence shall be utilized.
Build storage for materials, sleepers ... at the station.
Particulars:
+ Storage for special materials, cement, accessories: 30m2.
+ 04 rooms for workers with the standard 5m2/person.
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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

+ Kitchen: 20m2.
+ Bathroom, toilet: 20m2.
+ Guard department: 9m2.
+ Build yard for gathering materials.

+ Build yard for construction machine.
2.2 Materials gathering and collection.
During the construction process, old materials such as rails, sleepers, connection
accessories shall be moved to the designed place. At the designed place, the materials
shall be categorized into usable type and unusable type. The contractor shall maintain,
protect 24h/24h, and transfer to management unit when the Employer requests.
3. Measurement method for locating the constructions in the project
3.1
Site survey:
- After receiving the construction site, the Contractor shall conduct the examination of
poles in roads through national marks GPS by digital tachometer. In case there are
differences, the Employer, design consultants, consultants and supervisors shall be
reported to.
- All of existing roads shall be included in control network system.
- Relocate all of the road and bridge centerlines.
3.2
Other activities:
- The procedures are performed right after the contract is signed in order to create the
detailed construction plan and measures for train-operation safety, traffic.
- Tools for investigation shall be inspected.
- Measure the height of the road center, poles on curves.
- Locate the position of structures in station and mark them.
- Locate the position of culverts and channels.
- Put concrete into the marking poles.
- The measurement and investigation shall be conducted by experienced personnel.
- Update the changes of the construction status (level, alignment and bridge centerline)
in order to have measures for handling
4. Prepare the administrative formalities for the construction
- Contact with the station in order to obtain the train operation schedule.
- Ask for construction license, create the plan for blockade order, slow running order.

- Register the plan for wagons for supplying and transporting materials.
- Register temporary residency for personnel.
Cooperate with management unit, infrastructure management department, Sau bridge
in planning the detailed construction schedule.
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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

- Contact the management departments of the structures in the work site for solving
problems in the construction process.
- Contact with the waste department for disposing wastes.
IV. DETAIL OF CONSTRUCTION ORGANZATION
1. Preparation
-

Use theodolite,steel rule, and wood pole to locate the position of the bridge.
Use surveyor level to measure the level of construction.
Gather construction materials, equipment and machines.
Construct the access from the road to the bridge.
Remove the optical cables out of the construction site.
Prepare the site hut, transport the construction materials and equipment to the work
site.

- Make the beams for banding rail and bearing force.
+ Beam for bearing force: beam 3I550-4.0m long and 5.0m long, including 02
beams (old beams)
+ Beam for bearing force: beam 3I550-7.0m long, including 02 beams (new
beams)

+ Beam for banding rail: 5.0m long and include 02 beams.
- Make the V-shaped steel cage to brace rock gabion of temporary pier.
2. Plan for speed restriction and section blockade during construction:
- 15km/h speed restriction:
Apply for speed restriction in 40 days;
- Section blockade: apply for 1 time:
+ In 4 hours for installing new beam, disassembling the beams for banding rail,
and constructing the upper structure.
3. Construction work:
3.1. Install the temporary platform, beam for banding rail, potential well:
- Position: the temporary pier system for installing the beam for bearing force will be
at the upper part and lower part of the culvert. The center of the temporary pier system
at the upper part will be 7.00m from the center of the current railway. At the lower
part, it is 6.00m from the center of the current railway. The detail of installation will be
as below:
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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

+ Install temporary pole, platform: skim the soil and tamp the soil at the
position of the temporary pole until it reaches the designed level. Install the V-shaped
steel cage, lay ballast, fill the steel ashlar gabion, install cribwork 14x16x220, 2I350
beams and Pale. Install the new beam at the lower part, remove the old beam at the
upper part. The temporary platform is installed in the bridge center in front of the 2
abutments.
+ Construct the potential well at the upper and lower of bridge for bearing
capstan and tirfor.
+ Install the beam for banding rail at the abutment

+ The construction is carried out in the speed restriction 15km/h.
+ Complete the temporary poles and platform and to be checked before carrying
out the follow-up steps.
- In order to step up the construction progress and maintain the quality as well, the
contractor shall use machines to do the main tasks. Workers shall do the tasks which
are not main or that cannot be done by the machines.
3.2. Repair abutment head:
- Remove the old steel beam of the abutment and add the vertical and horizontal
connection system.
- Pass through the support, insert the wooden plate to support the existing steel beam. .
- Remove the cribwork, install the beam for banding rail.
- Excavate the soil below the beam for banding rail
- After that, we shall inspect the temporary structure and monitor the train operation
through the structure for 5 times in order to assure the safety
- Remove the old concrete at both sides of the abutment including: ballast wall,
abutment head, padstone, part of wing wall and abutment body
- Increase the connection between the new concrete and old concrete
- Install the reinforcing bar and formwork for the abutment
- As the concrete reaches 80% of the intensity R28, the formwork shall be disassembled.
- Install the reinforcing bar, padstone, and formwork according to the design.
- Notes when repairing abutment head:
+ Reinforcement installation complies with the design, installation of
workform must be close and flat.

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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

+ Concreting with concrete mixer according to the design. During the
process, concrete shall be tamped.
+ The formwork shall be monitored during the concreting process. If
formwork is deformed, stop concreting
+ Maintain concrete during the construction process.
+ The material, machine shall be out of the track gauge and guarded.
3.3. Construction of span structure:
- The main beam are manufactured and tested in the factory... Transport seperated part
to the construction site and stored there and then installed in succession. The parts of
main beam shall be installed manually at the upper. Notes for the connections with the
concrete layers: the drilled holes, connecting rivets... Paint all beams after finishing the
installation.
- Install the sleepers for supporting the beam.
- Install new steel beam on the platform at the lower.
- Put together each of part which is reinforced in order and ensure:
+ The parts shall be installed as deisgned.
+ Steel parts shall be flat and undeformed.
- The Supervision Consultant shall check and accept the installation of steel girder
first, next installation shall be continued.
- When finishing the installation of new steel girder the completion shall be done.
- Install workform, reinforcement, supporting equipment: drainage pipes, located
parts... and ensure:
+ Installation of reinforcement complies with the design.
+ The workform is close, flat and undeformed.
- The Supervision Consultant shall check and accept the workform and reinforcement
first and then carry out next item.
- When the beam meets requirements of intensity, the completion of girder shall be
done: construcion of anti-penetration layer, steel concrete network.
- The Supervision Consultant shall check and accept the workform and reinforcement
first and then construct next item.

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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

- Construction of water protection layer:
Water protection layer shall constructed after casting 3 days. Remove the cover, clean
the concrete surface and dry it before constructing anti-penetration layer. Install
drainage pipes and then spraying the anti-penetration in accordance with standard 0,2
litre per m², install steel net D2, cement mortar M100 with 4cm thick. When the
surface of mortar hardens cover it with the jute bags and spray water in at least 14
days.
- Notes for construction of span structure:
+ The installation and connection of the parts shall compy with the design and
in order avoiding the errors and wrong position...
+ Check carrfully and exactly the parts, mark the parts in order before putting
together.
+ Reinfocement structure shall meet requirements of intensity and quality.
+ Quality of paint and its thickness shall fulfill requirements of the
specifications of the project.
+ Install the reinforcement as designed, put together the formwork, padstone
closely and flatly.
+ Casting by concrete mixer as designed rate. During the casting use the needle
vibrator to tamp concrete, ensure the intensity and quality of new concrete and the
connection with the existing concrete as well.
+ Keep an eye on workform during casting, If formwork is deformed, stop
concreting. After having treated, the casting will continue and ensure the connection of
concrete among casting.
+ Maintain concrete during the construction process. After casting, cover the

concrete surface with jute bags, spray water in 14 days. After that remove the sides of
formwork, keep the steel side.
+ The material, machine will be out of the track gauge and guarded .
4.4.
Brace the slope, cone:
- Excavate the slope and cone according to design
- Excavate the cutoff dike and build the cutoff dike with ashlar
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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

- Construct K95 road bed
+ Fill each soil layer with 15cm thick, then tamp
+ Ask engineer to inspect and accept the work
- Lay ballast, construct the slope and cone with ashlar
• Ashlar work:
* Before construction of ashlar, it shall meet requirements as following:
Design the mortar components, test the construction stone and then submit the test
report on the mortar and stone to the Engineer for checking. The construction shall be
continued when the Engineer has no objection on such test report.
For ashlar: Shape and dimension of ashlar shall be processed by hand so that it meet
requirements of actual construction.
* Requirements of masonry work:
- Select the stone which are flat and equal to fill at the top side and then pointing.
- Completed surface of cone and slope shall be flat and equal. The Construction shall
be met requirements of flatness, height and inclination.
- Construction of cone and slope shall meet requirements of good looking as designed.
When constructing the flat side of stone shall be outside.

The check and acceptance work shall be carried out by the Supervison Consultant and
made a minutes of check and acceptance to control quality in the fufure.
* Drainage holes:
All slopes shall have drainge holes. These holes shall be in the lowest points where
water can be drained freely. The distance between the 2 holes, specifications and
design of the holes comply with the detailed drawing or the instructions of Supervision
Consultant.
- Adjust the longitudinal section of bridge approach.
3.5. Place the new beam onto the designed position:
- The day before placing the new beam, the designed position and construction
equipment have to be examined carefully.
- Blockade
- Remove the upper structure and beam of banding rail and lifting the existing beam,
install the position on the new abutment head and padstone.
- Move the existing beam to the supporting system in the upper.

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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

- Pull the new beam from the supporting system in the lower.
a. Remove the upper structure
- Remove rail, sleeper on the bridge and the road belong to the bridge area.
- Remove the beam for banding rail.
b. The horizontal screen of new beam:
- Roller (component for horizontal screen).
- Place 5T capstan at the lower roller path. Place 5T tirfor at the upper roller path.
- Each side will have a cable system. The cable type is 6x19+1, diameter of 19mm.

c. Measure for placing beam
- Lift beam
+ There will be 2 jacks and 2 back-up jacks at both ends of the beam. The jack will
be inspected and have same quality.
+ Assign experienced workers.
+ There will be at least 1 position for each jack to rest on.
+ there will be at least 1 position for each jack to rest on. The position must be
firm. There must be various nogs with different thickness. For each position there
are 2 nogs those are 60cm long.
+ The jack must be placed firmly on the concrete supporting and vertically with the
coated bar.
+ In one turn, only one end of the beam will be lifted 10cm.
+ During lifting beam, no workers is allowed to construct on the beam, no
vibration made on the beam.
+ There will be 2 jacks with same quality being placed symmetrically along the
beam.
+ As the beam lifted high enough, put the slide under the beam then prepare to pull
the beam.
- Move the existing beam to the upper

by the capstan.

- Pull beam

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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

+ Assign experienced workers to control the capstan. The workers must be in good
condition.
+ There will be personnel to monitor the move of the beam.
+ If the beam is not on the right path, the site committee must be informed .
+ As the beam comes close to the designed position (the remaining distance is less
than 50cm), the speed of the beam will reduce slowly and be pulled 2-5cm for each
turn of pulling .
+ The slide will be stopped so the beam can be placed.
+ Complete placing the beam
3.6. Complete the upper structure:
- Lay ballast: ballasts are transported by trains to work site and laid on the bridge and
add to the bridge approach.
- Install new prestressed concrete sleeper, rail P50 and fastening accessories: rails and
sleepers are transported by trains to the work site
- Add stone, adjust road:
+ Arrange rails, adjust gaps: use measure tools to inspect rails before adjusting rail
gaps. The line between the connection is not bigger than 20mm, the curve line is
not bigger than a half of shorted value. The connection will be tightened soon after
arranging rail .
+ Adjust the distance, complete the direction.
+ Complete the ballast layer. Collect the ballasts staying at the road shoulder
+ Inspect all of the work before the operation of train.
- During the construction process, material, machine will stay out of the track gauge
and be guarded.
3.7. Completion:
- Reinstall the optical cable in the original position.
-Remove the old beam, platform, temporary pole, beam for banding rail.
- Collect the materials, equipment and clean the watercourse.
- Gather the materials and store in the storage.

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METHODS OF CONSTRUCTION
LY BRIDGE – KM225+170

4. Construction quality control measures
- After finishing each item, we will ask engineer to inspect and acceptance and make
minutes of each of items.
- Supplement the maintenance and warranty for the construction accordingly with the
law.
- Unqualified materials will not be allowed to use for construction.
- Testing and inspection activity will be conducted according to the design document.
- The inspector can inspect any work item
- After the Engineer signs the acceptance minute, we will move to other items.
5. Completion, check, acceptance and hand-over:
- After finishing each item, we shall request the Engineer to check and accept that
item. The follow-up items shall be construct when the Engineer has accepted.
- Finish all of the procedures so that the work will be brought into service.
V. LABOR SAFETY MEASURES
1. Measure for train operation safety
* General measure:
+ Workers at the work site shall follow labour safety regulation, train operation
regulation of VNR:
+At work sites, there shall be safety supervisors for informing people about train
operation safety.
+ There shall be warning signs at both ends of the site
+ The telecommunication railway shall not be affected during the construction
+ The structures outside the track gauge must be firm and not be destroyed by storm
in order to avoid affecting the train operation safety

+ The work items which require section blockade must be constructed only when the
blockade order is ready.
+ Assign personnel, material according to decision 1578/1999/QĐ-BGTVT
+ Material shall be placed out of the track gauge
+ In case of storm, flood, there shall be personnel to monitor and handle the effect of
the weather. If the effect cannot be managed, train operation may be stopped
+ Workers shall be educated about railway regulation including decision 187 QDDSVN

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