THUYẾT MINH BPTC ĐƯỜNG ĐÔ THỊ MỘC BÀI, TÂY NINHENGLISH

This work includes the preservation of trees and other objects that are allowed to keep The natural ground surface of these types of area must be excavated and eliminatedthe organic soil

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DESCRIPTION OF TECHNICAL AND CONSTRUCTING METHOD

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PART I: KNOWLEDGE AND AWARENESS OF THE BIDDER TO THE

CONSTRUCTION PROJECT AND SITE.

1.1 Information of tender

- Name of tender: Construction of Moc Bai Urban Roads

- Name of project: Greater Mekong Sub-region Corridor Towns Development Project

in Moc Bai – Tay Ninh

- Employer: Tay Ninh Greater Mekong Sub-Region Corridor Town DevelopmentProject Management Unit (Tay Ninh PMU)

- Location: Loi Thuan Commune, Ben Cau District, Tay Ninh Province

- The Construction of Moc Bai Urban Roads is approved through Tay Ninh EconomicZones Authority’s Decision No 140/QĐ-BQLKKT issued on the approval of constructionproject: “Greater Mekong Sub-region Corridor Towns Development Project in Moc Bai –Tay Ninh” dated on July 26, 2012 Moc Bai Urban located in the west of Tay NinhProvince, nearby Cambodia border, 60km from Ho Chi Minh city Moc Bai Urban located

on the urban economic corridor town, under axes: TransAsia railway, highway HCM City Moc Bai, National road 22, the position facilitate Moc Bai Urban in relation to the nationaland international on road and railway

-The aim of this project is to create a good environment to change through investbudget to the prior urban infrastructure and enhance the holding competence in towns andcities This is appropriate with developing strategies of the programs and area cooperationstrategies and it will contribute to the implementation of National cooperate strategy of theADB Country Collaboration at of each participating country

Tay Ninh Economic Zones Authority issued Decision No 140/QĐ-BQLKKT on theapproval of construction project: “Greater Mekong Sub-region Corridor TownsDevelopment Project in Moc Bai – Tay Ninh” dated on July 26, 2012

1.2 Scale of Bid:

The scale of bid is performed as below:

Road Đ.N1A: Starting point at Border Guard Post (Dia Xu Bridge) and the ending

point crosses road Đ.D11 (on ĐT786, 100m from Dia Xu Bridge) Length of the roadL=3.03km

Road Đ.N1B: Starting point at the end of D11, 100m heading to Trans-Asia

Highway from Dia Xu Bridge, the ending point is about 200m from the intersection withroad Đ.D23 Length of the road L = 2.20km

Road Đ.D10: Starting point at the centre of Đ.N25 (old name 75A) at Km1+606.13,

the ending point crosses road Đ.N1 Length of the road L=2.27km

Road Đ.D11: Starting point at the centre of Đ.N25 (old name 75A) at Km1+758.02,

the ending point is at right angles to Road Đ.N3 and the horizontal curve to road Đ.D11.Length of road L=1.31km

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Road 51: Starting point at the intersection with ĐD.7 (old name: road 28) and the

ending point at the intersection with ĐD.23 of Moc Bai urban area Length of roadL=2.94km

Note: (*) length of the road is adjusted as the actual size.

II. CONSTRUCTION SPECIFICATION

4x6 crushed stone with soil thickness… cm (review the structure) Pavement :

 Pavement tile Tezzaro thickness: 3 cm

 Cement mortar : C8 thickness: 2cm

 Concrete layer C8, crushed stone 4x6, thickness: 10 cm

 Laterite gravel layber K≥0.95, thickness: 20 cm

2.2 Drainage system:

Regarding excavation road base, all longitudinal ditches are stabilized by cementconcrete, so water will flow along ditches to drainage locations on the alignment road Forembankment road base, the water will flow under the natural terrain

Designing the longitudinal drainage, including: Ditch (ditch slab); Sump; Odourcontrol manhole; Manhole; Culvert pipe; Outlet gate

2.3 Lighting system:

According to standard TCXDVN 259:2001

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2.4 Technical conduit system:

In order to provide a favorable conditions for the construction and installation ofpipeline infrastructure in the future as underground power lines, telecommunication cables,technical conduit system is proposed to be set at intersections

2.5 Traffic sign system, traffic organizing and traffic safety:

Fully invest in every road, ensure of traffic safety and no roadblocks according toQCVN 41:2012/BGTVT “National sign regulations” and current regulations

2.6 Green space:

In accordance with National Standards TCVN 362: 2005 “Urban green space”, thestandard of project for trees along roads

III TERRAIN, GEOLOGY, CLIMATE AND HYDROLOGY FEATURES

III.1 Terrain feature

Moc Bai urban area lies on flat ground, relatively low (elevation about +0.00m to+4.00m) and steep from North West to South East The highest area is the surrounding ofthe border gate, with average elevation above +3.0m The lowest area in the South Eastwhere there are flooding grass fields, with average elevation +1.0m to -0.3m There aremany river, ditches, and channels The North lies Dia Xu channel flowing east-west fromVam Co Dong river to the borderline Vam Co Dong is in the East; in the South there aresome small ditches and flooding, low land

Around the urban is fields, swamps and bushes In the West urban, the Cambodiaborder gate area has now developed to a lively residential area The North lies Ben Cautown with low-rise buildings

III.2 Geology feature

Through area geological survey result, the stratum of the research is described in orderfrom the top to the ending bottom of the survey scope of boreholes, there are layers asbelow:

* Report of geological survey of Construction Road Đ.N1A: :

+ Layer Đ: is the granular backfill, with clay and sand This layer can be found

at most of the boreholes (except HK9) Thickness of the layer at the boreholes variesfrom 0.6m (HK3) to 1.0m (HK8)

+ Layer 1: Dark grey clay mud and plants This layer is found in someboreholes in the area Its thickness varies from 0.3m (HK3) to 0.8m (HK2); elevation ofthe layer’s bed varies from 0.98m (HK3) to 0.35m (HK1)

+ Layer 2: Vicous red-brown fine sand mixed with with clay This layer isfound in some boreholes in the area Its thickness varies from 0.8m (HK6, HK7) to1.1m (HK5); elevation of the layer’s bed varies from 1.06m (HK6) to 0.52m (HK5).+ Layer 3A: Clay mixed with with fine sand, red spots, white grey, light yellow.State: softly viscous Its thickness varies from 0.9m (HK4) to 1.4m (HK9); elevation ofthe layer’s bed varies from -1.06m (HK9) to 0.03m (HK8)

+ Layer 3B: Clay, white grey, light yellow State: hard viscous This layer isfound in some boreholes in the area (except HK6) Its thickness varies from 1.6m(HK4, HK5, HK9) đến 5m (HK8); elevation of the layer’s bed varies from -3.72m(HK3) đến 2.83m (HK1) Drill did not reach the layer’s bed at HK8

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+ Layer 3C: Clay mixed with with little light yellow sand, red-brown State: halfhard – hard This layer is found in most boreholes in the area (except HK8) drill did notreach the layer’s bed.

Summary of main physico-mechanical properties of the main layers

Soil

desciption

Natural water content

Wet density

Void ratio

Plasticity index Consistency

Internal friction angle

Cohesion force C

* Report of geological survey of Construction Road Đ.N1B :

+ Layer 1: Dark grey clay mud Main elements are clay, dust, and organicsubstance State: watery This layer is found in some boreholes in the area (exceptHK6) Its thickness varies from 0.5m (HK2) to 3.5m (HK7)

+ Layer 2: Silty clay, softly viscous – haft hard Main elements are clay, dust,sand; color blue grey, yellow, red-brown This layer is found in some boreholes in thearea (except HK5, HK6); drill did not reach the layer’s bed (except HK8)

+ Layer 3: Mixed with clay, watery viscous – hard viscous Main elements areclay, dust, sand and sometimes laterite grit; color blue grey, brown-yellow This layer isfound in some boreholes in the area (HK5, HK6, HK8); drill did not reach the layer’sbed

Soil

desciption

Wet density

Void ratio

Plasticity index Consistency

Cohesion force C

* Report of geological survey of Construction Road Đ.D10 :

+ Surface layer (only described): Black soft mud layer, at (HK2, HK4).Thickness 0.2 – 0.3m and white fine sand layer at (HK1, HK3)

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+ Layer 2: Clay, clay mix laterite grit; color: yellow red, white grey, red grey,yellow red; state: hard viscous – hard High viscosity Layer 2 lies right under surfacelayer and even deeper than bottom of the borehole.

y ratio Void Plasticit y index Consistenc y

Cohesio

n force C

+ Top layer (only described): Black soft mud layer, at (HK2, HK3, HK4).Thickness 0.3 – 0.6m and white fine sand layer at (HK1)

+ Layer 2: Clay, clay mix laterite grit; color: yellow red, white grey, red grey,yellow red; state: hard viscous – hard High viscosity Layer 2 lies right under surfacelayer and even deeper than bottom of the borehole

Soil

desciption

Wet density Void ratio Plasticity

index

Consistency

Internal friction angle Cohesion force C

+ Top layer: Clay mixed with black humus, sand and white clay This layer isfound in some boreholes in the area, lies from the ground surface to the depth of 0.2m(HK1, HK2, HK3, HK4)

+ Layer 1: Clay – white and yellow mixed with clay State: hard viscous – halfhard Low viscosity This layer lies under top layer Thickness of this layer varies from0.6m (HK1, HK2) to 0.7m (HK3) Elevation of the layer’s bed varies from 0.85m(HK1) to -0.22m (HK4)

+ Layer 2B: Clay mixed with laterite grit; color: grey mixed with red-brown,white grey mixed with red-brown, yellow with white spots… State: half hard – hard.High viscosity This layer is found in some boreholes in the area (HK1, HK2, HK3,HK4) It lies under layer 1; and drill did not reach the layer’s bed

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According to the result of the supplementary geological survey conducted byTedi South for the route from Km 1530 to the end of it with 7 boreholes in September

2015, the distribution of the layers is as below:

+ Layer K: is the top layer Clay mixed with organic substance; dark grey; softlyviscous This layer is found in all of the boreholes Its thickness varies from 0,3m (HK-BS1) to 0,5m (HK-BS5) The elevation of they layer’s bed varies from 0,10m (HK-BS5) to 0,40m (HK-BS1 & HK-BS2)

+ Layer 1A: Clay with high vicosity (CH), Dark grey, white grey, sometimesmixed with organic substance; state: watery – watery viscous This layer is found inboreholes HK-BS5, HK-BS6 và HK-BS7 Its thickness varies from 1,3m (HK-BS5) to2,6m (HK-BS7) Elevation of the layer’s bed varies from -1,20m (HK-BS5) to -2,30m(HK-BS7)

+ Layer 1b: Clay with low viscosity (CL); Yellow brown, white grey;sometimes mixed with grit and gravel; state: soft viscous This layer is found in allboreholes Its thickness varies from 0,9m (HK-BS3) to 2,7m (HK-BS5) Elevation ofthe layer’s bed varies from -0,70m (HK-BS3) to -3,90m (HK-BS5)

+ Layer 2: Clay with low vicosity; Blue grey, white grey, yellow brown, redbrown; sometimes mixed with laterite grit; state: hard viscous – half hard This layer isfound in all boreholes However, the drill did not reach the bottom of they layer Thethickness of the drilled layer varies from 2,5m (HK-BS5) đến 5,7m (HK-BS3)

Soil

description

Natura

l water conten t

Wet density

Void ratio

Plasticit

y index

Consis tency

Cohesion force C

Conclusion: Most of the roadbed lie on weak geological substance with high void ratio,

low intensity, high compressibility and settlement Therefore, we would concentrate on thebase treatment before constructing of the pavement layer on it

III.3 Climate feature

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The climate in Moc Bai have the features of climate of Tay Ninh province: it isrelatively temperate and divided into two season: dry season and wet season Wet seasonstarts from May to November; and dry season starts from December to April.

Futhermore, the local barely suffer from stormy weather and other unfavorablefactors Besides the advantages, some main disadvantages of this place is the variation andspecific differentiate of the factor in each season

The contrast between dry season and wet season, rainfall regime, wind regime andmoisture regime somehow becomes the obstacle to the development of manufacturing andliving

Properties of the project area’s climate:

 Air temperature:

Average temperature in 2004- 2006: 27,40C-27,50C

Highest-average-temperature month is April: 28,50C-29,60C

Lowest-average-temperature month is December: 25,50C-25,70C

 Air humidity:

Average humidity in 2004-2006: 76,7% - 79,7%

Highest-average-humidity month is July, August, and September: 80% - 89%

Lowest-average-humidity month is December, January, and February: 71%

67%- Rainfall intensity:

Rainfall intensity of year 1655 mm

Highest-rainfall-intensity month is October: 334 mm

Lowest-rainfall-intensity month is February: 56 mm

 Sunshine duration:

Highest sunshine hour in a day: 8,3 hour

Highest sunshine hour in a day: 5 hour

 Wind:

2 main wind seasons every year:

Dry season: Southwest wind or West – Southwest wind

Wet season: Northeast wind

In general, the climate is relatively moderate, barely suffers from storm, flood as well

as natural disaster

III.4 Hydrological feature

As being affected by the rain regime and wind regime, the surface flow is alsodivided into two season: floody season and dry season

Floody season occurs in the area in May to November anually Dry season occurs inDecember to April of the following year

As for hydrologic, the local surface water depends on of Vam Co Dong river Vam

Co Dong river start from the high hill with the height of 150m in Cambodia; its flow indirection of Northwest – Southeast with the total length of 220km A part of the riverbelongs to Moc bai urban area about … km

Vam Co Dong river flow to Bau Quy intersection (Can Duoc, Long An province),then merge with Vam Co Tay river and flow into the sea The valley area is 8.500km2, the

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water flow rate is 96m/s Besides Vam Co Dong, the area also has ditches starting fromVam Co Dong river flow inside the land, which create waterway system; drainage ditchesdistribute all over the area from the north to the south.

1 Hydrological survey result: (According to the supplementary hydrological survey

result on road Đ.N1A and 51 of project Construction of Moc Bai urban conducted by TEDI SOUTH dated on October 03, 2015).

 Hydrological regime of the area

The area’s hydrological regime is the same as the hydrological regime of Vam CoDong river

+ In the dry season and when there are small diluvial rains, the water level ofthe ditches and small rivers dependent on the tide of Vam Co Dong river The level ofwater is up and down in an irregularly semidiurnal cycle When the tide is up, the flowdirects from Vam Co Dong river to the borderline of Vietnam and Cambodia; when thetide is low, the flow directs from the borderline of Vietnam and Cambodia to the Vam

Co Dong river

+ In floody season, especially when there are extreme diluvial rains, the flowonly direct to Vam Co Dong river and the period of this flow direction is more than onemonth

+ The most extreme dilivial rain in the area occurred in 1978, 1996, 2000, 2001,

2011, and 2013 with the flood in 2000 is the most extreme flood in the past 50 years

 Survey’s highest water level.

+ At the border guard post in the starting point of road Đ.N1A (110 06’ 13’’ N,

1060 09’ 15’’ E) is the highest water level in 2000 Hmax 2000 = 2.18m, time of theflood is about 1 month Highest water level in 2013 Hmax2013 = 1.68m (0.5m lowerthan the highest water level in 2000) (information collected from local citizen frequently

go past the post and from the borderline soldiers)

+ At Dia Xu bridge on ĐT786, the ending of road Đ.N1A (110 06’ 09’’ N, 106010’ 54’’ E) is the highest water level in 2000 Hmax 2000 = 2.01m, time of the flood isabout 1 month Highest water level in 2013 Hmax2013 = 1.68m (0.33m lower than thehighest water level in 2000) (information collected from Mr Nguyen Van Hoa, 47 yearsold, Thuan Tay hamlet, Ben Cau district)

+ At the double electric post on the left of the road connecting Trans-Asiahighway with Thuan Dong hamlet, near the pontoon bridge (Bailey bridge on Dia Xuditch 110 05’ 50’’ N, 1060 12’ 30’’ E) is the highest water level in 2013 Hmax 2013 =1.40m Highest water level in năm 2000 Hmax2000 = 1.90m (0.5m higher than thehighest water level in 2013) (information collected from Mr Nguyen Van Non, 55 yearsold, Thuan Dong hamlet, Loi Thuan commune, Ben Cau district)

 Water level at Go Dau Ha hydrological station

+ TEDI SOUTH has updated statistic of water level to the end of 2014 of GoDau ha hydrological station (at the pier of Go Dau bridge) At the station, the years withhighest water level is Hmax1978 = 1.43m, Hmax1996 = 1.53m, Hmax2000 = 1.80m,Hmax2001 = 1.33m, Hmax2011 = 1.25m, and Hmax2013 = 1.21m The highest waterlevel ever in Go Dau Ha station within 20 days is 1.45m (from October 03, 2000 toOctober 22, 2000) and the highest water level since 2001 in Go Dau Ha station within

20 days is 0.85m

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+ At Go Dau Ha station, the average water lever throughout years is Ha =0.35m.

+ According to series of 53 highest water level each year statistics, and applyingPearson type III distribution, TEDI SOUTH has drawn the highest water level curve anddetermined at Go Dau Ha station H1% = 2.02m, H4% = 1.59m

 Road design water level:

+ The frequency of highest water level is 4%: The frequency of highest waterlevel 4% is used to determine the height of road shoulder According to the correlation

of highest water level between the survey points and Go Dau Ha station:

oRoad 1A : The starting point (Border guard post H2000 = 2.18m) has H4% =1.97m; The ending point (Dia Xu bridge on ĐT786 H2000 = 2.01m) has H4%

=1.80m The height of road shoulder design is applied to the road curves allover the road

oRoad 51 : The starting point (the natural landform height about 2.7 - 2.9); theending point (as the pontoon bridge H2000 = 1.90m) has H4% =1.69m Theheight of road shoulder design is applied to the road curves all over the road.+ The height of highest water level within 20 days: The height of highest waterlevel within 20 days is used to determine the height of pavement layer bed According tothe correlation of highest water level between the survey points and Go Dau Ha station:

oRoad 1A : Starting point has H20 = 1.83m (as H20 in 2000) and H20 = 1.23m(as H20 in 2012); Ending point has H20 = 1.66m (as H20 in 2000) and H20 =1.06m (as H20 in 2012) The height of pavement layer bed design is applied tothe road curves all over the road

oRoad 51 : Starting point (high natural landform, not affected by the water ofVam Co Dong river); Ending point has H20 = 1.55m (as H20 in 2000) and H20

= 0.95m (as H20 in 2012) The height of pavement layer bed design is applied

to the road curves all over the road

 Conclusion:

As the design process did not mention of the water level frequency within 20 days, tomake the height of the road design is harmonious with the other roads in the urban area, thehighest height of water level within 20 days of 2012 is chosen to be the design height ofwater level in order to determine the pavement layer bed and the height of the 5 roads of theproject

IV SCALE AND SPECIFICATION OF DESIGN

The design scale of the routes is in accordance with the Decision BQLKKT of Tay Ninh Economic Zones Authority issued on the approval of constructionproject: “Greater Mekong Sub-region Corridor Towns Development Project in Moc Bai –Tay Ninh” dated on July 26, 2012

No.140/QĐ-4.1 Scale of construction of Road Đ.N1A:

+ Length (include the intersection): L = 3.03km

+ Starting point: at Border guard post (Dia Xu bridge)

+ Ending point: intersection with internal road Đ.D11 (on ĐT786, is the startingpoint of road Đ.N1B)

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Construction technical standard is defined as below:

+ Asphalt concrete pavement grade A1, horizontal gradient 2%

+ Road’s cross section:

+ Construction type: Urban road

+ Construction grade: grade III

+ Calculated speed: V= 50Km/h

+ Load capacity of road: single axle 120KN

Standards of technical geometry is in accordance with TCXDVN 104-2007:

2 Minimum radius of horizontal curve m 80

4 Radius without super-elevation design m 1500

5 Length of super-elevation run-off equivalent to

7 Braking distance or Stop sight distance m 55

8 Minimum reversing sight distance m 115

10 Minimum length of grading transition m 80 (50)

11 Minimum radius of convex vertical curve m 800

12 Normal minimun radius of convex vertical

13 Minimum radius of sag vertical curve m 700

14 Normal minimum radius of sag vertical curve m 1000

15 Minimum length of vertical curve m 40

Design contents of book II 1 includes construction items:

+ Road;

+ Soft ground treatment;

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+ Rainwater drainage;

+ Culvert – technical tank;

+ Lighting and trees

Typical cross section of Road Đ.N1A

4.2 Scale of construction of Road Đ.N1B:

+ Starting point: at the end of Đ.D11 ( on ĐT786, is ending point of roadĐ.N1A)

+ Ending point: about 200m from the intersection with road Đ.D23

+ Asphalt concrete pavement grade A1

+ Construction grade: grade III

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No Criteria Unit Value

5 Length of super-elevation run-off equivalent

16 Minimum length of vertical curve m 40Design contents of book III 1 includes construction items:

+ Road;

+ Soft ground treatment;

+ Rainwater drainage;

+ Culvert – technical tank;

+ Lighting and trees

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Typical cross section of Road Đ.N1B

4.3 Scale of construction of Road Đ.D10:

Scale of construction of Road Đ.D10:

+ Starting point: intersection with road Đ.N25

+ Ending point: intersection with road Đ.N1

+ Construction grade: grade IV

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15 Minimum length of vertical curve m 35Design contents of book IV 1 includes construction items:

Typical cross section of Road Đ.D10

4.4 Scale of construction of Road Đ.D11:

+ Length (include the intersection): L = 1.31km;

+ Starting point: the intersection with roaf Đ.N25;

+ Ending point: intersection with Đ.N3

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+ Construction type: Urban road.

12 Normal minimun radius of convex vertical curve m 700

15 Minimum length of vertical curve m 35

Design contents of book V 1 includes construction items:

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+ Trees.

Typical cross section of Road Đ.D11

4.5 Scale of construction of Road 51:

+ Starting point: intersection with road ĐD.7

+ Ending point: intersection with road ĐD.23

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15 Minimum length of vertical curve m 35Design contents of book VI 1 includes construction items:

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Typical cross section of Road 51

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PART II – TECHNICAL MEASURES FOR ROAD CONSTRUCTION

A PREPARATION

I Preparation for construction

The preparation steps for construction:

1 The Contractor coordinates with the Investor to deal with the local authority onthe administration procedures, settlement of executing work, preparation for the work site,office, laboratory, storage yard for material, casting concrete components, and siteclearance

2 Together with the Investor, the Supervising Consultant Engineer allocates thework site, then restores and marks the route centerline, highest mark and other detailedmarks of the curves; sets up additional bench-marks, construction sign posts; checks andcompares the design document with the actual site; executes locating the work site

3 Mobilize specific machinery and equipement for the work

4 Execute manufacturing the materials or sign contracts of supplying assets asrequired by the work progress

5 Execute measure for assets and materials transporting, at the same time test thephysico-mechanical standards of each material: soil, sand, crushed stone aggregate,bitumen, cement, iron, steel and other concrete aggregate ingredients standards; and submitthe results to the Supervising Consultant Engineer

6 Prepare all the necessary tools and equipment and traffic signs system on theconstructing route

II Road forming:

Road forming is the work with its aim is to stabilize the main parts of the actual crosssection of the road to ensure the construction as in the design The document for theconstruction to base on is the drawing of vertical section horizontal section and plan of theroad

During setting road forming, the road form stakes may be lost so they have to bemoved out the work site Besides, the level machine and other equipment for measuring theform and elevation of the base shall be used in constructing

As for the embankment base case, road forming consists of determining elevation ofembankment at the centerline of road and the edge of road, determining slope embankmentbottom soil extracting sites (if available) The road form stakes at low embankment areerected at the marks of every 100m and additional marks; at high embankment base andcurves, the space between piles shall be 5-10m

As for the excavation base case, the road form stakes shall be kept out from the worksite These stakes shall have the location and the depth of excavation described on them anddetermine the edge of the slope of excavation base During excavating, the rulers shall beused frequently to check the slope gradient When excavating close to the design depth, theelevation of excavation base is determined by the holes excavated along the centerline ofroad and edge of road until reaching the design elevation and then that elevation shall beused as standard elevation

As for the the side ditches and line ditches, the road form stakes are set at thecenterline and edge of the ditch and are also kept out the work site

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B MEASURE OF EXECUTING CONSTRUCTION ITEMS

I CONVENIENT CONSTRUCTIONS MOVING, SITE CLEARANCE AND

ORGANIC EXCAVATION

1 Scope of work:

“Site clearance” consists of removing the trees, grass, plants, clearing the organicpieces and ploughing the surface soil layer in the construction site according to the scopementioned in the approved design drawings The limited area of the work site includes thearea of the cross section adding 3m expanding on each side (from the top of slope ofexcavation base or toe of slope of embankment base) This work includes the preservation

of trees and other objects that are allowed to keep)

The natural ground surface of these types of area must be excavated and eliminatedthe organic soil layer of the surface layer according to the limits and depths mentioned inthe design document: The areas of lake, and ditches,… laid on by the base shall beexcavated the organic layer (if available) completely which is mentioned in the designdocument before embanking the base

The Contractor shall mark the location and limit of the area in need of removal oftrees, grass, plants, organic pieces and ploughing the surface soil layer at the applicableplaces and submit the Supervising Consultant to consider and decide the work that needs to

be performed and appoint the plants and other objects that are allowed to keep

We have the useful measures for safety and warning for the constructing sites andsignal lighting at night

The centreline and edge marker posts, and benchmarks shall be led out ofconstruction affecting area by the supplementary stakes The Contractor shall fix andprotect the supplementary stakes carefully Avoid lead the supplementary stakes to the

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storage yards, traffic road, and the places which are likely to be sunk, eroded and slipped…

soil-Requirement of the location and road forming is to locate the centerline, constructionaxis, toe of slope for embankment base case, top of slope for excavation base case, retainingwall, edge line of the foundation ditch, edge of material mines, width of the side ditches andline ditches, the cross sections of the embankment or excavation,…

Use the measuring machine with high accuracy to locating the construction TheContractor shall arrange the survey unit frequently available at the site to supervising,checking the centreline, construction mark posts during constructing

b The tasks:

All the objects on the natural ground including plants, trees, grass and other obstaclesmust be removed completely except the harmless objects lying under at least 01m thealtitude of base or the top of base slope The Contractor does not have to remove the treesand other objects that can be kept according to the Supervising Consultant

As for the shallow foundation ditches (dikes, canal, small foundation) with the depth

<0.5m, the Contractor shall remove all the tree and its root

The limits of soil excavating to utility embank and utility excavate, limits of baseembanking with the height of embankment less than 0.5m, limits of soil storage yard andthe place to extract soil must be cleared

At the places which the altitude of embankment base higher than natural ground 1.50m, all the plants, trees and roots, grass, rubbish and other organic pieces must becompletely removed Use the mechanized vehicles to excavate the trees After unearthing,the trees must be moved away so as not to obstruct the constructing

Use the bulldozer with equipment to excavate the tree, the excavator and specificsystem for removing the tree with diameter less than 0,50m

As for the trees with diameter larger than 0.50m and wide growing root, mine shall

be used

Only keep the tree within the limits of base with height of embankment base >1.5m

If the embankment base is 2m, the trees shall be cut close to the ground, if the embankmentbase is higher than 2m, the trees may kept 10cm higher from the natural ground

The organic soil layer must be removed or the top soil layer (or the mud layer)according to the approved design document

The rich soil layer within the stipulated area of the design foundation ditch of theconstruction shall be removed and stored to recover the damaged ground duringconstructing in the future, ect…

When scooping, storing and managing, rich soil cannot be contaminated with water,rocks and rubbish There shall be measures to reinforce the top of slope, growing grass onthe surface to avoide erosion The temporarily borrowed ground for constructing must berecovered according to the completion progress Within 03 month after the constructionhandover, all the temporarily borrowed ground shall be fully recovered and returned to theowner

c Backfill and place of dumping:

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The Contractor shall backfill with the filling materials responsive to technicalstandards for the holes from excavating trees and the holes after moving the obstacles withthe compaction different from the required compaction (except the excavation base).

All the materials from the site clearance and soil ploughing must be dumped away.Arrange the redundant material at the selected site with the approval of the SupervisingConsultant Any material shall not be burnt

Use the excavators combined with bulldozers to remove and destruct the convenientconstructions;

The removal or destruction of the existing constructions performed by the Contractorwithin the area or neighbouring of the road segments and landmarks shall be instructeddirectly by the Consultant or as mentioned in the drawings

Use the dump truck to move the removed objects to the stipulated dumping site

II CONSTRUCTION OF BASE

1. Excavation of excavation base:

- During the work, when excavating to the design altitude and reaching unsuitablematerial, the Contractor shall notify the Supervising Consultant to have a punctual method

to deal with it and ensure the quality of the construction

- The excavated material shall be dumped in the right site, cleanly and harmless tothe surrounding plants, construction and properties

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- When the excavating exceeds the limits mentioned in the design document, it must

be filled with suitable materials and tamped at compaction K≥95

- The excavating across operating underground technical system, must have thepermission of the underground technical system management unit or the local authorityunit Centreline, landmarks of the underground technical system must be defined clearly onactual site and set with high stakes to be easily seen During the work, there must befrequent supervision of the authorized represenative of the construction unit and theunderground technical system management unit The Contractor has to perform themeasures to avoide damaging to the underground technical system

- In case of discovering the underground technical system , constructions orarchaeological site, arms depot, caster caves,… which are not mentioned in the design, theexcavating must be stopped and notified to the representatives of the authorized unit tocome to the site to solve the case

- The excavating shall be perform as the progress and procedures as other workingphases to provide favorable conditions for embankment and drainage

- Altitude and size of the base must be adjusted to be suitable to the requirements ofwork procedures and design document During work, frequently check the top of the slope,direction, altitude to ensure the excavation completion is responsive to the requirements.Invite the Supervising Consultant to check and excavate the ground to the suitable altitude

- When excavating to the design altitude, the Contractor and Supervising Consultantshall conduct testing and collecting the soil model to determine the physico-mechanicalstandards of soil Conduct rolling the soil layer 30 cm thick below the bottom of roadfoundation reaching K  0,98 If the excavated materials is not responsive to the requiredquality, conduction of replacement responsive soil shall be made

2 Construction of embankment base:

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+ Plants, trees, grass or other unsuitable materials must not be used for theembankment base The plant cover in the embanking base must be removedcompletely by bulldozer or grader until it is free from roots and grass.

+ Do not use alkali, and soil containing much salt and gypsum (ratio of salt andgypsum over 5%), silty soil, and humus soil to embank

+ Clay soil (with clayish fraction less than 50%) shall be only used at the dryground, not floody, quick water drainage at the toe of the road, the altitude ofembankment is from 0.8 to 2.0m

+ When embanking the base in the floody area, the good drainage materials likestone, sand, mixed sand shall be used

+ The quality of embanking soil shall be check and collect the model by theSupervising Consultant right at the mine and supervised its testing at the laboratory.+ The embanking material meet the requirement of compaction K≥0.95(according to 22TCN 333-06) must be responsive to the below requirement:

 CBR (soaked in 4 days) at least 5%

+ The embanking material K98 can bear the load CBR at leasr 8%, compactionK>=98 (according to 22TCN 333-06), in case there is no materials responsive to theabove requirement, the Contractor shall propose another suitable material to replace.This procedure shall be inspected by the Supervising Consultant and submitted to theInvestor and authority units to consider and decide

Technical requirements to embanking material K98Technical standard Testing method Required numeric testing

valuePassing sieve max TCVN 4198-2014

* Procedures of embankment base:

- Clear the admixture, organic substance, plants on the embanking ground

- Grading by bulldozer according to design document

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- Inspect the quality of embanking material; transport the embanking material (fromthe excavation base) by dump truck.

- The bulldozer to grade the dumped soil into layer, rolling until reach the requiredcompaction

1.1 Preparation before embanking

Before embank the base, buil water drainage system, surface drainage first, thenditch excavation and embanking causeway,…

Excavate small ditches to drain the stagnant water and then at sunny time repair thesewet sureface to make them easily dry

Before the earthwork, clear the admixture, organic substance, plants and big rocks onthe working site by excavator and grader

In the area of bankment, removed all the top soil, humus soil, organic substances,organic soil,… to the stipulated depth To clear the organic soil, we use the bulldoze at theplace the landform is favorable In the narrow places or obstructed places, we clear it byhand

All the tree within the working area shall be removed completely and excavated todepth of 0.5m and backfilled with the appointed materials not mixed with humus, organic,roots or other admixture and tamped by jumping jact compactor at the suitable compaction

All the redundant material shall be dumped in accordance with instruction of theInvestor or Supervising Consultant and shall not be burnt

After excavating for removing the top soil layer to the design depth, if discover softground, we shall notify the Supervising Consultant for treatment method suck as:

- Scarify the top soil, air-dry and ramming by the roller until reaching requiredcompaction

- Excavating and removing the soft ground and replace it with another good waterdrainage soil appointed by the Supervising Consultant and ramming until reachingreaquired compaction

- In case the foundation is soft and cannot be improved by pumping water orexcavating more, the embanking material shall be gravel or rock which are well drainageand they shall be ramming as stipulated The thickness of drainage layer can be about 50cm

or as instruction of Supervising Consultant

- As for the segments of embanking base at the tangent to the structures like culverts,ditches and existing construction, there must be suitable constructing measure to avoiddamaging the structure

In order for new embanking material to well bind to the slope and the top of slope ofold embankment base, bench-cut before embanking with soil, these benches have the lengthand width suitable for the thicnkess of the embanked soil layer and ensure the width for theconstruction equipment to perform The suitable material excavated from the grade shall beused as embanking soil

The entire ground after organic excavation, plant cut and root removal is benchcutting and rolling until reaching the require compactor

According to the standard:

- K = 0.98 within 30cm from the bottom of the surface

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- K = 0.95 within 30-80cm from bottom of surface.

After completing the ground within the scope until being inspected and accepted, weshall conduct the next segment construction

The final size and form of the embankment base shall be set by the Contractor underinstruction and acceptace of the Supervising Consultant The forming shall be performedwith wood stakes, stretching wire and marks on the fixed objects

1.2 Embankment of the base

Constructing measure depends on the width of embankment and the height ofembankment base But in order to ensure well binding between the new embanking basesegment and the natural ground, and the intensity of the newly embanked base, the generalrequirement for all the cases is bench-cutting the top of slope of embankment base beforeembanking new segment and embank layer by layer from the bottom to the top, carrefullyramming Definitely do not embanking horizontally because of not ensurance of thecompactor, the base shall sink and slide Furthermore, the embanking soild should be thesame type as the embankment base

When bench-cutting, each bench must be wide enough (depends on the constructingmeasure) for the grader and vibrator to work Each surface transverse of the bench shall becalculated from crossing point of the natural ground to the vertical edge of the previousbench As for the bench-cutting material, the bench shall be embanked with suitablematerials, same type and rammed together with the new material of the embankment base.The bench-cutting and excavating ditches shall be kept for the surface before dryembankment

The general constructing measure shall depend on each cases whether to use themechanized equipment or mainly by hand

In case the expanded width is wide enough for the machines to move up and down,the dump truck shall be allowed to transport the soil and place directly at the site and use thebulldozer preliminarily to grade and use the grader to grade and use the roller to roll untilreaching the require compaction If the vehicles cannot directly dump at the constructingsite, the soil shall be dumped at the proper site and then use the bulldozer to bulldoze thesoil and grade into layer to ram

In case the expanded width is narrow or embanking on the grading slope but theexpanded segment is low, the constructing measure shall be by hand or moving the soil bythe machines (bulldozer, truck,…) from the expanding excavating segment or from the soilmine along the route and from the old route push the soil down to embank the expandedsegment Notice that the soil pushed down must be graded into layer and rammed rightaway by manpower

In the cases abover, we should use the compactor which is suitable to work in narrowplaces like jumping jack compactor, mini compactor… Only use the roller in the favorablelandform, large work volume, long expanded segments, and especially when the expandedsegment is wide enough ( >2,5m )

After completing the constructing, all the measures as the new base constructing tocontinue embanking until the base reaches the new design height

As for the embankment base at the head of the artificial constructions:

If the embanking soil nearby the structures like immediate precast culverts orheadwalls of culvert, longitudinal ditches,… only execute embanking when the concrete

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structure reaching over 70% design intensity; and be really carefull so that the area next thethe construction is not rammed too fast that causes collapsing or put the construction undertoo much pressure

When the embankment base crossing the places that used to be the digged holes, ordifferent places that usual compactor cannot be used, the embankment at the places mustcomply the stipulated requirements for filling foundation ditch until usual compactor can beused at those places

1.2.1 Execution of ramming and rolling test:

- Before widely constructing, the Contractor shall propose in writing on the plan ofcompaction test to determine the construction equipment line, required numbers of rollingstroke, and the method to adjust the water content

- During constructing, if there is any amendment in embanking materials orconstruction equipment, the Contractor has to execute supplementary compaction tests andsubmit the testing survey to the Supervising Consultant Engineer for approval

- During constructing, the Contractor shall completely comply with the preparedcompaction procedure and request by the Supervising Consultant Engineer

- The Compaction testing is completed before the official applied constructing

- After compaction, the average density of the trial paving shall be determined by theaverage of the results from the density-testing sample at the site, the testing site shall berandomly chosen

1.2.2 Work procedure:

- The materials used in embankment base work which are extracted from material minesmust be responsive to the standards stipulated in the technical standards of the Project Theembanking materials shall be conducted in layers with the thickness of each layer 20cm to thedesign altitude

- Transporting the embanking materials from the mines to the work site is conducted indry weather, paved down and grade into layer with determined thickness and ensured ofeven thickness before being compacted

- Arrange the stroke of the grading equipment and soil transporting vechicles in alogical manner so as to get the most out of the compacting function when transporting thoseequipment, minimalizing ruts and uneven compacting

- During grading, ensure the cross slope, well drainage, avoid water stagnant on rainydays When grading each layer, expand the grading out of the road sides 0.5m as designed

so that the compaction equipment can perform fully its function at the edge of road whenmoving safely on the edge

- During compacting, frequently inspect the altitude, geometrical size and the flatness

of the layers Ensure suitable water content of the embanking materials If the water content

is too low, supplement of water is needed In case the water content is too high, measures ofploughing, excavating drainage ditches and other measures appealed to the requirements ofthe Supervising Consultant Engineer

- The Compaction equipment is capable of meeting the requirements on compactionwithout harming the compacted materials The compaction equipment and compactionprocedure shall comply with the prepared and approved procedures

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- During the constructing, frequently inspect the density of the compacted layer bymeans of testing methods at the site or the approved methods If the testing results at anysite having the actual density failed to meet the requirements, the Contractor shall conductcorrection to ensure the required density

- After finishing the embankment base, the Contractor invites the SupervisingConsultant Engineer to inspect on altitude, geometric size, flatness and density of thematerials If the above criteria meet the technical standards and are confirmed ofacceptance by the Supervising Consultant Engineer, continue on the work of next layer

1.2.3 Inspect and managing the quality of work and inspection:

- The materials before and during constructing is fully inspected on the requiredquality as stipulated Checking the quality of material mines before embankment or every10,000m3 of embanking material, a test shall be conducted, each time collecting 3 randomsamples and calculating the average number of 3 samples The criteria to be inspected:

+ Density of soil grain;

+ Elasticity modulus (E) or CBR,

- The base shall be inspected on every layer (each layer ≤ 20 cm) Only continue towork on the next layer until the previous layer is responsive to the requirements Thematerials used on embankment at the depth of 30cm-50cm below the bottom of pavementsurface must have the density K≥0.98; the other embankment base must have the densityK≥0,95

- The density of the embankment base is inspected randomly according to theassignment of the Supervising Consultant, and is conducted throughout the depth ofembankment The space between the density inspection points does not exceed 200m Asfor the embankment soil surrounding structures or culverts, density inspection for each layershall be conducted As for the embankment base, every at least 500m3 of placed materialshall be inspected on density At least 1500m2 of each compacted embanked-soil layershall be conducted a group of 3 actual density inspections at the site If the inspectionresults reveal the actual density at any site fail to meet requirements, the Contractor shallexecute correction for a responsive density Less than 5% of the amount of sample can havethe density <1% of required design density but they are is not allowed to be in the same site

- It is not allowed for the embankment base to be sink and have constantly

omnidirectional long cracks and blister on the embankment base

- The top of slope, route direction, altitude and width of the base, ect… must becorrect, accurate and suitable to the drawing and technical constructing procedure, orsuitable to other instructions accepted by the Investor and Supervising Consultant

- The base embanked at the design altitude, conduct inspection on the criteria below: + Deviation of the embankment crest width is not less than one in the design,every 50m conducted one inspection

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+ Deviation of cross slope and superelevation rate not exceed (+, -) 0.3%, every50m conducted one inspection on one cross section by level machine

+ Deviation of the gradient of side slope is not larger than one in the design,every 20m conducted one inspection by measuring machines

+ Deviation of the centerline axis of the road, every 50m conducted oneinspection on one point and points of curvature and points of tangency

+ Deviation of altitude on vertical section lies in scope from -20mm to +10mm ,every 50m conducted one inspection on one point on the centerline axis of the road+ Deviation of flatness of the slope is measured by the widest rut under ruler 3mfor the 50mm slope of embankment base On the same cross section, constantlycheck on the surface of slope to find out the widest rut

3 The measures to ensure transportation and construction quality.

+ Before excavating or embanking the base of road, drainage system must bebuilt, firstly the surface water drainage (water from rain, pond, lake, ditches,…) toavoid flowing into the foundation hole and the base of construction Excavateditches, canals and embank the causeway,… according to the landform and nature ofthe construction

+ When excavating conducted in the places under the underground water, it isnecessary to have measures in surface and underground water drainage inside andoutside of work site Arrange drainage ditches, collector wells, package pumpingand drainage pump station for each constructing segment Definitely avoid waterstagnancy and its influences to the base of road

+ The entire water drainage system is maintain in good condition duringconstructing

+ Use the wood stakes, measuring tape, reference point to limit the excavationarea during constructing If possible, fixed objects like trees, water drainage structure

or unmoving stones shall be marked to be based on to check to finished work in thefuture Submit to the Supervising Consultant to consider before executing theremoval excavation The Supervising Consultant shall consider and decide the work

to do and appoint the plants and other objects to keep

+ To ensure the transportation on the route, during constructing, the excavatedmaterial shall be graded cleanly and quickl moving to the stipulated site, sweep allthe dirt scattering on the existing road surface to avoid boggy and slippery road onrainy days

+ When the excavated soil is not moved away from the site due to some reason,the soil shall be dumped into piles to avoid obstructing to the transportation on thatroute and construction equipment operating on the site When dumping the redundantsoil from the excavation base at the upper slope, continuously dump into dykesleading the water out so as not to flow into the base of road When dumping theredundant soil from the excavation base at the lower of the slope, dump interruptedlyinto separate piles for easy water drainage

+ Water drainage system installation is conducted along with the roadwork,ensure the surface of the road always be dry

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- If the excavated soil is qualifiable enough for embankment and with the approval ofthe representative of Investor, we shall take full advantage of the excavated soil to embank

at the embankment road Redundant soil and unqualifiable soil for embankment shall bedisposed and moved to the dump site as instruction of the Supervising Consultant

- The material is disposed with the approval in writing of the Consultant Engineer and

is not dumped near the culverts or the upstream weir

- When excavated close to the design altitude, the excavation should be terminate toleave a sinking prevention height for the influence of the moving of vechicles and machinesduring constructing

- If excavating over the design altitude, conduct backfilling with accepted material andcompacting to the design density stipulated in the design or as technical instructions TheContractor shall be liable for all the costs due to the backfilling and compacting

- After excatvating to the design altitude, the constructing unit shall execute to collectsample to test its physico-mechanical standard to determine whether it is responsive to therequirement for the surface If it failed to meet the requirements, the representative of theInvestor shall appoint to excavate and dispose and replace the soil with another responsivesoil type Then the ploughing and rolling for compaction ensurance shall be performed andclean before continuing to work on the foundation of road

- The slope after being excavated shall be smoothen to ensure proper grading fordifferent geological type to avoid sliding, sudden collapsing

- Unresponsive material shall be disposed with the approval in writing of theConsulting engineer The Contractor shall be liable for placing the material in ensurance ofgood-looking of the site and not harm to the plants, construction and other neighbouringproperties

- The stored soil shall be piled up tidily in a reasonable manner and not obstruct thework

- If the contractor places the material at the wrong place and has no permissions of theConsulting engineer, we shall rearrange it at our own expense

- During constructing the pavement, the road form is kept dry, easy for drainage, theside ditch running from excavation base down to embankment base shall be made carefully

in order to avoid erosion damaging the embankment base

- In order for embankment base and foundation layer not to be wet, the Contractor has

to buil drainage canals or suitable ditches so that the water shall be drained out from thework site

- The damages to the pavement and other existing or constructing constructions cause

by carelessness in drainage system, we shall have positive mesures to repair at our ownexpense

- The excavation shall be conducted in harmonious with the work progress andproceduce of other work phases to create favorable condition for pavement and drainage atany time and any where

- The excavation shall be suspended in the weather condition in which paving andconpacting on the embankment base according to approved design document is not allowed

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- Altitude of the base shall be constructed according to the construction procedurerequirements and technical criteria mentioned in the approved design document underinstruction of Supervising Consultant engineer

- The Contractor has consider about the influence of construction process toenvironment and study carefully this issue In a certain time, the constructing shall notaffect much to the ecological environment and water environment

Inspection, management on constructing quality and acceptance:

- All the slope route direction, altitude, width of pavement must be accurate andsuitable to the design drawing and construction technical procedure Any deviation must be

in allowable range or suitable to other instruction with permission of the Investor andSupervising Consultant

Allowable geometric deviation:

T

1 Pavement crest width inspection conducted every 50m Not smaller than one in design,

2 Cross slope and superelevation ≤±0,5%, inspection conductedevery 50m on a cross section

3 Deviation of slope gradient is not larger than

4 Deviation of centerline <10cm, Each 20m measure onepoint but do not create more

curves

5 Deviation of altityde on vertical cross -20mm to +10mm, 50m measureone point on centerline axis

6

Smooth of slope surface is defined by the

widest rut under ruler 3m to the slope of

embankment base

50mm

7 Altitude of excavation base -20mm, Each 20m measure onecross section

8 Deviation of grade of excavation base

≤0,25% of the grade, measure atthe grade change point on the

10 Slope of excavation base measured with ruler3m 20m measure one cross sectionThe sinking point <8cm, Each

- The deviation mentioned in the table above are the maximum acceptable values andonly occur less than 5% of total inspection points and are disperal, not gathering in a area

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Inspection and evaluate the quality:

- Before constructing on the foundation of the road, inspection and valuation of thebase must be conducted

- The inspection can only be conducted only after the inspection items are fulfilled andthe quality is responsive to requirements of design

- After accomplishing the work, make acceptance minutes for work phase transitionbefore continuing other next tasks

III EXECUTION OF DRAINAGE WORK:

1 Scope of work:

Execute errecting the drainage constructions of the locations mentioned in designdocument The erection is responsive to the requirements of location, direction, altitude,gradient mentioned in the approved construction drawing and as instructions of SupervisingConsultant

This work consists of all the foundation excavating, foundation compacting, andfoundation backfilling according to the location, altitude, gradient and the cross sectionesmentioned in the detailed design drawings in the approved construction design document

2 Measure of constructing execution:

The culvert routes lying on the routes of the tender have its function of surface waterdrainage and load a large amount of water from the basins along 2 sides of the road

According to the basic design approved at Decision No 140/QĐ-BQLKKT by TayNinh Economic zone management department dated on July 26, 2012, distribute 02 culvertroutes along the sidewalks of the route in order to collect water from the surface and basinsalong two sides of the road and to the drainage gate mentioned above The arrangement of

02 culvert route along two sides of the road also ensures the connection of drainage system

of other sub-projects along the road in the future

Measure of constructing:

+ Mechanized combines manual

+ Construct all the drainage system to ensure the embankment of the base.Arrange transportation during constructing if necessary In common cases, thematerials are gathered before executing errection work

* Mechanized:

- Excavate foundation with excavators; move the materials (sand, stone, cement,culvert pipes, ) to the work site and move the redundant soil to the dump site with truck

- Load and unload precast components by crane truck

- Use jumping jack compactor and rod vibrator to compact the concrete mortar

- Use mixing machine to mix the building mortar, concrete mortar

* Manual:

- Fix, complete foundation ditch

- Move the material and construction equipment of light weight and short length oftransporting

- Excavate at the places which mechanized equipment can’t reach; finish culvertfoundation ditch

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- Coordinate with machines in installing culvert, work on culvert joints and proof

water Place concrete, build headwalls, wingwalls, reinforce upper and lower pool culvertapron

- Backfill finished culvert and continue working on the other lane

Excavation of culvert foundation:

- During constructing, execute working respectively on each side of the road to ensuretraffic fluency, work from the lower to the upper stream

- Base on approved construction design document and instructions of SupervisingConsultant, execute placing stakes to locating excavating holes

- Use excavators to excavate culvert bedding, manually fix and complete the segment

as right altitude and size right after it is excavated The excavated soil shall be used forembankment or be dumped at the stipulated site Execute simple bench excavation andmultiple bench excavation to avoide sliding and erosing

- At the places where the loading capacity of the foundation at the design altitude isnot responsive or inappropriate, the Contractor shall excavate and dispose the material andreplace with another accepted suitable material, and compact it as requirement of theSupervising Consultant

- When excavating to the design altitude, check the gradient of the bottom of theculvert bedding; if it is responsive to the requirement, execute grading the bottom of theculvert bedding

- Execute compacting the foundation to avoid losing connection between pipes If thefoundation ground is soft, we shall execute measures to treat with the approval ofSupervising Consultant

- The bottom of the culvert bedding in excavation base must be compacted as currentrequirement Any damages of the bottom of the culvert bedding must be excavated deeper

as request of the Supervising Consultant The excavated part shall be replaced with suitablematerial and compacted to the required altitude of the bottom of culvert bedding

- After completing treating the soil of culvert bedding and being inspected bySupervising Consultant in specific writing, we shall continue the work according to thedesign

a Work on circular culvert, precast box culvert: the following work is executed as below:

* Foundation preparation:

- The material used for foundation of culvert is mentioned in the construction designdocument with the approval of Supervising Consultant The Supervising Consultant canrequest the Constructor to alter the material for foundation

- The size of the foundation layer is in accordance with the construction designdocument

- After the culvert bedding is excavated, construction of culvert foundation andplacing must be conducted right after receiving approval of Supervising Consultant

- Use the level machine to check to ensure the altitude of culvert foundation at theculvert placing point as the design altitude

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- Construct the culvert foundation with rubble and mortar, the design thickness foreach culvert is approved and instructed by the Supervising Consultant.

* Inlet and outlet:

- The structure of inlet and outlet is constructed with concrete or stones as stipulated indesign document, suitable with the drainage system to form a natural and smooth flow

- Any culvert placed not straight or sunk shall be lifted up and re-installed; theContractor shall pay all the cost for the activities at it own expenses

- There must be an appropriate camber for the culverts placed under embankment basewithout piling foundation, even when it is not mentioned in the design document, in order tominimize the slumping when being influenced by the loading of soil filled above

- The camber of the culver does not depend on the geological condition under bottom

of the foundation, the embankment height and planned slumping of pavement above whereculvert is place

 Joints:

- The joints are packed with joint material (plastic gasket) or with the mortar accepted

by the Supervising Consultant

- The ratio of cement mortar must be as the technical requirements

- The surfave of the culverts must be clean and wet before being caulked with mortar.Before installing the culverts into their positions, conduct caulking the mortar to the insideand outside of the culvert joints The joints shall be covered with canvas to keep being wetwithin 7 days at least It must be free of dust, excessive mortar and other material left insidethe culvert during installation

 Maintaining and moving of culverts:

- Load and unload culverts by means of rolling the culverts on a battered plank or anyother inclined plane if there is no approvals in writing of the Supervising Consultant

- The Contractor shall use crane to uplift and lower the culvert pipe to avoid damages

- Any damaged culvert pipe shall not be brought into use and paid by the Contractor

- When finishing lowering and adjusting the position of culverts, execute constructingthe headwalls, wingwalls, absorption trench and reinforcing the upstream and downstream

of the culvert

* Embank the foundation ditch:

- Execute embanking in layers of 15cm thick and tightly vibrating with jumping jackcompactor The two sides of culvert must be embanked with soil to avoid all the harmfulforces caused by lateral pressure Vibrate on both sides to ensure the slump of culvert is thesame as one of the ground or the slump is minimized When backfilling, notice the water-proof cover of the culvert pipes During vibrating, avoid damaging the water-proof cover ofthe culvert

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As for the box culvert with transition slab, when embanking to the altitude of thebottom of transition slab then install the transition slab

- Use manpower to fix the slope and embank the pavement

When constructing culvert, we shall construct on each side of road respectively toensure the traffic and construct from the lowerstream to upperstream When constructing,

we shall use bamboo stakes or fence to separate the constructing area

During constructing, in case of any deviation from the document, the Contractorshall notify the Supervising Consultant and Construction management unit to find anappropriate solution

When finishing constructing, only when the Supervising accepts then the traffic shall

be opened and the other half of culvert shall be constructed

b Constructing cast-in-site box culvert, technical tank:

- The culverts casted right at the site should be executed in dry season to avoiddisadvantage of weather

- Constructing culvert on each side of road respectively to ensure the traffic andconstruct from the lowerstream to upperstream

- Arrange tents and constructing groups near the culverts

- The materials are gathered fully and collected samples as stipulated procedures andapproved by the Supervising Consultant

- The steel formwork is manufactured, fixed and inspected before being brought intouse

- Add crushed stones and vibrate with jumping jack compactor

- Install cement concrete formwork buffering bottom of culvert

- Erect reinforcement bars for the bottom and walls of the culvert

- Erect bottom formwork, wall of the culvert and pour concrete

- During constructing, frequently check the altitude and geometric size of the culvertwith level machine and steel ruler

- Install formwork of the culvert cover, set the reinforcement bars for culvert cover andpoor cement concrete

- Install reinforcement bars and formwork for wingwalls, headwalls, apron and pourcement concrete right at the site

- Foundation of headwall and cut-off wall are separated from the culvert body withsoft joint This soft joint is padded with gasket (or canvas) soaked bitumen or wood soakedbitumen as the stipulated procedure in the design drawing approved and instructed by theSupervising Consultant

- Construct and reinforce the upperstream and lowerstream apron by quarry stoneswith mortar on crushed stone underlayer

- Embanking must be carefully conducted Each layer must be vibrated at thestipulated density in the approved design document The requirements on materials arementioned in the pavement backfilling

- Reinforce and press the slope with stones and mortar on the compacted crushed stoneunderlayer

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Vehicles can only move above the box culvert with the approval of the SupervisingConsultant.

- During constructing, every step must be inspected and accepted by the representative

of the Investor before continuing other steps

- After finishing constructing culvert, only when reaching the standard intensity (28days) and being accepted by the representative of the Investor, the concrete constructionshall be opened to transportation and removed the temporary roads (if available)

- As for the small cuvert after being backfilled, only when reaching the standardintensity (28 days) and being accepted by the representative of the Investor, the items shall

be opened to transportation and the rest half of culvert shall be constructed

* Detailed measure of box culvert construction:

Box culvert blinding concrete:

Blinding concrete work

- The Contractor shall set the axes with theodolite, place the benchmarks and pourblinding concrete to foundation ditch, fulfilling the requirements on size and height asrequirements

- Use the rod vibrator to vibrate the blinding concrete

- The surface of blinding concrete after vibrated must be flat in order for later setting

of reinforcement bar

- After finishing laying blinding concrete, stop to wait as the technology requirementand then execute erecting reinforcement bars, formwork and placing concrete for bottom ofculvert according to the design

Constructing the culvert:

One day after laying blinding concrete, execute the constructing the culvert and theexecution is divided into 3 phases:

- Constructing bottom of culvert

- Constructing wall of culvert

- Constructing culvert cover

* Procedure of box culvert work:

- Installing reinforcement bars for the bottom of box culvert

- Setting formwork for bottom of box culvert

- Casting bottom of culvert with concrete

- Installing reinforcement bars for walls of box culvert

- Setting formwork for walls of box culvert

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- Casting walls of box culvert with concrete

- Setting formwork for cover of box culvert

- Installing reinforcement bars for cover of box culvert

- Casting cover of box culvert

- Precast reinforced concrete manhole

Reinforcement and erection of reinforcement bar:

Reinforcement bars used for the project must be the types mentioned in the drawing

or equivalent types that are responsive to National Standards TCVN 1651-2008, TCVN

197-2002, TCVN 198-2002 » Other requirements: cutting, bending, binding, quality - theacceptable deviation is as Article 4 of National Standars TCVN 4453-1995

The deformed steel bars with protruding ridges must have the product certificate ofthe manufacturer for the using steel

 Maintainance of reinforcement bars

The reinforcement bars cannot be left on the ground as well as outside for a longtime The Contractor must mark each type of steel bar and store them separately The newsteel bars must be kept separately form the old ones so that the representative of Investor cantest the samples when in need

 Bending reinforcement bars

The reinforcement bars shall be bended as the stipulated size and installed to theposition mentioned in the drawing The bars must not be bended or straightened in a waythat they can be damaged All the work to do with bending must be applied to cold-worksteel

When necessary, the Contractor should clean the rust on the reinforcement bars bymeans of using the steel brush to clean the grease or other harmful substances before thebars are installed and casted with concrete

 Processing reinforcement bars

The reinforcement bars must have the shape and size as required and are processed in

a manner that does not damage the material

The Contractor shall ensure the reinforcement bars are bended as the size mentioned

in the drawing enclosed to this part

Do not weld the steel bars at high temperature

 .Erection of reinforcement bars

The bars must be cleaned to get rid of grease, rust and other harmful substancesbefore being installed and casted with concrete All the reinforcement bars must be keptstably in position with steel wire when casting and tamping Ensure the thickness and theproctection concrete layer Depending on puspose, use spacers made from mortar or plasticspacers (or bar chair) at least 4 spacers per 1m3

Representative consultant of the Investor shall check the installation of reinforcementbars before casting If the installation has been performed a long time before casting, thesebars shall be cleaned off rust and other harmful substances

 Binding reinforcement bars

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The binding of reinforcement bars should be performed as least as possible and thebinding must comply with the National Standards In any case, the Contractor shall submittfor permission of the representative consultant of the Investor on binding method andbinding position.

All the binding joint must not be 30 time shorter than the diameter of the bar andtightly tied at many points with steel wire

Formwork:

This is one of the most important task in concrete work This task partiallydetermines the good looking and accuracy of the construction Therefore, the Contractorshall focus on the type of the formwork to install In this construction, the Contractor shalluse the type of formwork below :

Formwork of bottom, wall, and cover of the culvert are forming steel form At thespecific shape, plywood formwork 30mm thick shall be used

Box culvert bottom formwork:

The bottom formwork is installed when finishing the erection of reinforcement bars

of the bottom After finishing laying the foundation bottom, the geodetic unit shall executere-locating the center of the culvert, then install formwork to stabilize the two sides Thecontractor shall use tole formwork combined with wood formwork

Check the centerline, core, altitude and position of the formwork with theodolite,level machine until they meet the technical requirements in the design then executioncasting shall be approved by Supervising engineer

Remove formwork after 48 hours as long as frequently maintain the concrete as procedure

Box culvert wall formwork:

Wall formwork is the forming steel formwork installed after finishing installing thereinforcement bar for the wall of the culvert This task plays an important role inconstructing for its major affect to the constructing progress of formwork and reinforcementbar installation of culvert cover The geodetic unit shall determine the center of each wall inboth manner of marking with red paint The formwork has been prepared well in advancebefore being brought into installation Rectangular formwork is the combination of formingsteel formworks binding with formwork clamps

Apply radial system on each side of the culvert formwork with 2 vertical steel barsU50 at space of 0.65m and standing steel bars U50 at space 2m to support the formwork,combine steel formwork turnbuckle anchor 8 obliquely placed to the bottom and placedcrossed the fromwork walls The turnbuckle is anchored to the bottom of the culvert withsteel hook 8 fixed in the base of culvert when casting and 1.2m away from the toe ofculvert wall

Use the theodolite and level machine to check the accuracy of the center, core andthe straight standing of the wall, and note down in the construction diary before casting

Other norms must comply with the regulations and procedures of the state

Culvert cover formwork:

- Use PAL scaffolding combined with wood purlins and steel purlins to support all thestructure of culvert cover structure; use steel formwork as formwork for bottom of the

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culvert cover The cover slab is placed on two layers of wood purlin The upper layer ispurlin 80x100 a400, and the lower layer is purlin 100x120 on the PAL scaffolding.

- Prepare measure to prevent the formwork from being deformed, notice the edge andthe upper surface must be cleaned before casting

- All the pending holes and details set in advance shall be marked on the formwork’ssurface clearly and stably during casting

- The culvert cover formwork is detailedly shown in the detailed construction drawing

of detailed box culvert cover formwork

- Before installing reinforcement bars, inspection and acceptance on entire formworksystem to avoid errors and deformation

After installation, we shall clean all the formwork and reinforcement bars beforecasting

Formwork removal:

Formwork and scaffolding to support the structure (culvert cover) shall be removedafter the concrete reaches necessary intensity to load its volume and other loading andaffecting forces during constructing

Concrete work:

General issues on concrete casting of the structures:

After carefully inspecting the formwork and reinforcement bars conducted bySupervising and Investor, if the formwork and reinforcement bars are responsive to therequirements, the Contractor shall conduct concrete casting

Checking the center, core, and other pending details to ensure there is no deviationsafter concrete casting and installation of formwork for the following parts

The concrete casted for the box culvert is commercial concrete: trucks carry theconcrete to the casting site, the concrete is poured with concrete pumper, tamp the concretewith electric vibrator (use fuel vibrator in case electric runs out)

Casting concrete for upper surface shown in the concrete work design As thevolume of concrete is relatively large, and requirement on surface quality is high, theContractor shall use the concrete at intensity as stipulated The thickness of concrete layers

is suitable for the size of the structure and tamping machines During casting, arrange levelmachines constantly checking the altitude Besides, arrange casting reinforcement squaregrating 2m x 2m to be easily kept track on The foundation casting is divided into phases.After graded and tamped, the concrete foundation shall be smoothen according to therequirements of design

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The concrete shall be casted by the workers under instruction of the site personnel toensure the concrete work follow correct procedure and requirement

During concrete casting, comply as below:

Do not make the position of formwork, reinforcement bars, thickness of theprotection concrete layer other pending details vary from the standard position

If the reinforcement bars are wraped and crooked, they must be set straight beforebeing casted

Install work platform so that the staffs and workers do not damage the reinforcementbars while moving

Notice the altitude of the concrete surface of all the casting structure (the altitudeshall be marked before concrete casting), do not higher or lower in comparison to one in thedesign The surface of concrete must be carefully processed

c Manhole work:

 Manhole :

 The space between manhole is from 30m – 40m

 Use the cover slab of reinforced concrete crushed stone 1x2 M200

 Wall of manhole: reinforced concrete crushed stone 1x2 M200, thickness20cm

 The manhole is placed on a base of concrete and crushed stone; thickness 10cm

 The phases of constructing manhole for waste water drainage:

 Manhole location

o Before constructing, the site manager shall direct the technical staff andmeasuring group of the unit to execute measuring segment (route) of drainagesystem When necessary, coordinate with the measuring group of the contractor

at the office Major contents of location work:

 Locate axis, center of the segment (route) of constructingdrainage

 The crossing point of the segment (route) with other drainageroute or technical route (water supply route, communication route,…) orwith other underground constructions

 The location of other construction on the constructing segment(route): drainage gate, culvert

 The drainage segments (routes) which are transitions indirection, altitude or specific requirements

 The border, area of earthwork: width of ditches, top ofexcavation slope, toe of embankment slope, the cross section (necessary)

 The results of measuring of the actual site must be shown on thedrawing and measuring note

d Technical conduit:

Conduit work:

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THUYẾT MINH BPTC ĐƯỜNG ĐÔ THỊ MỘC BÀI, TÂY NINHENGLISH

Main content of traffic safety measure

Measures to ensure the quality of specific works