SPEC TIẾNG ANH lộ tẻ RẠCH sỏi technical specification kien giang EN

SPEC TIẾNG ANH lộ tẻ RẠCH sỏi technical specification kien giang EN SPEC TIẾNG ANH lộ tẻ RẠCH sỏi technical specification kien giang EN SPEC TIẾNG ANH lộ tẻ RẠCH sỏi technical specification kien giang EN SPEC TIẾNG ANH lộ tẻ RẠCH sỏi technical specification kien giang EN SPEC TIẾNG ANH lộ tẻ RẠCH sỏi technical specification kien giang EN SPEC TIẾNG ANH lộ tẻ RẠCH sỏi technical specification kien giang EN SPEC TIẾNG ANH lộ tẻ RẠCH sỏi technical specification kien giang EN

MINISTRY OF TRANSPORT (MOT) CUU LONG CORPORATION FOR INVESTMENT, DEVELOPMENT

AND PROJECT MANAGEMENT OF INFRASTRUCTURE (CUU LONG CIPM)

DỰ Á N XÂ Y DỰNG TUYẾN LỘ TẺ RẠCH SỎI

AND PYUNGHWA ENGINEERING CONSULTANTS LTD.

TABLE OF CONTENTS

Page DIVISION 2 - SITE WORKS

DIVISION 3 – EARTH WORKS

DIVISION 4 – WATERWAY WORKS

DIVISION 5 - ASPHALT PRODUCT AND PAVEMENT

Section 6.1 Precast concrete Piles 6.1

DIVISION 7 – NOT APPLICABLE

DIVISION 8 - MISCELLANEOUS

DIVISION 9 - ELECTRICAL WORKS

DIVISION 10 - DAYWORKS

DIVISION 2

SITE WORKS

DIVISION 2 - SITE WORKS

TABLE OF CONTENTS

2.1 - Site Clearing and Grubbing 1

2.2 - Demolition and Removal of Existing Structures and Obstructions 5

2.3 - Diversion & Protection of Existing Utilities 11

SECTION 2.1 - SITE CLEARING AND GRUBBING

TABLE OF CONTENTS

1 DESCRIPTION 2

2 CONSTRUCTION REQUIREMENTS 2

2.1 General 2

2.2 Clearing and Grubbing and Tree Removal 2

2.3 Topsoil Stripping 2

2.4 Protection of Areas Designated to Remain 3

2.5 Disposal of Cleared Material 3

3 MEASUREMENT AND PAYMENT 3

3.1 Method of Measurement 3

3.2 Basis of Payment 4

SECTION 2.1 - SITE CLEARING AND GRUBBING

1 DESCRIPTION

This work consists of clearing, grubbing, removal of top soil, and removal and disposal of all vegetation and debris within the project limits, excepting those objects designated to remain in place or to be removed in accordance with other sections of these Specifications

This work also includes the preservation from injury or defacement of all vegetation and objects designated to remain

2 CONSTRUCTION REQUIREMENTS

2.1 General

The Engineer will establish the limits of work and designate all trees, shrubs, plants and other things to remain The Contractor shall protect and preserve all items designated to remain

2.2 Clearing and Grubbing and Tree Removal

(a) All surface objects and all trees, timber, rotten wood, stumps, roots, snags, brush, other vegetation, rubbish, and other protruding obstructions, not designated to remain, shall be cleared and/or grubbed, including disposal as required

to a depth at least 50 cm below the original ground surface and at least 50 cm

below the bottom of the designed lowest pavement layer

less than 50 cm below the finished subgrade level

(d) All pits, channels and ditches shall be cleaned of unsuitable material

(e) Voids left after removal of roots shall be filled with suitable material and compacted

2.3 Topsoil Stripping

(a) In areas under roadway embankments or where designated by the Engineer, the Contractor shall remove the topsoil and dispose it of as directed by the Engineer

is sufficiently fertile to encourage or sustain the growth of vegetation

by the Engineer, and the topsoil that in the Engineer’s opinion can be re-used shall be stockpiled separately from other excavated material

(d) Where topsoil is to be used for dressing of the slopes of embankment or other areas as directed by the Engineer or as indicated on the drawings, the work of topsoil stripping will be deemed to include stockpiling of topsoil when necessary as well as removal, placing and spreading of topsoil in areas designated by the Engineer In which case, the work shall be measured and paid only under Specification Section 3.5 “Embankment Construction” After spreading, the topsoil shall be raked to form a smooth surface free from weeds, roots, sods and large stones

2.4 Protection of Areas Designated to Remain

In areas designated by the Engineer, the Contractor shall be responsible for the protection and routine maintenance of existing shrubs, trees and grassed areas On completion of the Works these areas shall be returned to the Employer in the same condition as before and any damage due directly or indirectly to the Contractor's operations shall be made good at the Contractor’s own expenses

2.5 Disposal of Cleared Material

(a) The Contractor shall have the right to use un-saleable timber (or saleable timber when permission is granted in writing by the appropriate government agency or authority) for his own purposes in connection with the Contract; always provided that he has ascertained and complied with the requirements

of the relevant government agency or authority

or near the right-of-way as directed and shall be trimmed and stacked in accordance with the requirements of the relevant government agency

(c) All other timber, except timber to be used, and all brush, stumps, roots, logs, and other refuse from the clearing and grubbing operation shall be disposed

of at locations provided by the Contractor

(d) The adjacent areas shall be left with a neat and finished appearance No accumulation of debris shall remain on or adjacent to the project

3 MEASUREMENT AND PAYMENT

3.1 Method of Measurement

(a) Clearing and grubbing, demolition and removal of existing structures and obstructions, and protection of designated areas, included in the work for Site Clearing, shall be measured in square meters Quantities will be based on the field measurements and volumes approved by the Engineer

be measured in cubic meters Quantities will be measured and approved by the Engineer

(c) Removal or protection of trees, regardless of their size or nature, shall not be

measured or paid separately, and shall be deemed included in the work of Site Clearing

3.2 Basis of Payment

Payment for Site clearing and Excavation organic soil shall be based on actual quantity that accepted by Engineer, suitable with approved drawing and BOQ Quantities that out of approved drawings or other areas shall be borne by the Contractor Quantities in structure foundation, channel relocation,… shall be measured follow related pay items in this Specification

SECTION 2.2 - DEMOLITION AND REMOVAL OF EXISTING

STRUCTURES AND OBSTRUCTIONS

TABLE OF CONTENTS

1 DESCRIPTION 2

2 WORK REQUIREMENTS 2

2.1 General 2

2.2 Removal of Drainage Structures 3

2.3 Removal of Curbs 3

2.4 Removal of Pavements, Footpaths, etc 4

2.5 Removal of Traffic Signs 4

2.6 Removal of Buildings and Structures 4

3 MEASUREMENT AND PAYMENT 6

SECTION 2.2 - DEMOLITION AND REMOVAL OF EXISTING

STRUCTURES AND OBSTRUCTIONS

1 DESCRIPTION

Demolition and Removal of Existing Structures consist of the removal, wholly or in part, and satisfactory disposal of blocks of masonry of an individual size greater than 1 cubic meter, of all buildings, hedges, fences, structures, pavements, curbs, and any other obstructions which are not designated or permitted to remain Demolition includes the salvaging of designated materials and proper backfilling (in accordance with specification requirements) of any and all trenches, holes and pits resulting from demolition and removal work

Right of way acquisition may not be completed in all areas at the start-up of the construction period and the Contractor shall schedule the work associated with this Specification section accordingly

Obstructions or other items that are designated for removal and disposal elsewhere

in the Contract Documents shall be dealt with in accordance with so stipulated requirements

2 WORK REQUIREMENTS

2.1 General

Demolition and Removal of Existing Structures by the Contractor shall be provided, within and adjacent to roadways, and on the right-of-ways, as shown on the Drawings or as directed by the Engineer

(a) The Engineer may instruct that materials recovered from demolition work shall remain the property of the Employer unless specifically provided otherwise in the Contract Documents

damage, in sections or pieces that may be readily transported, and shall be stored by the Contractor at specified places on the project as directed by the Engineer

(c) Basements or cavities left by structure removal shall be back-filled with acceptable material to the level of the surrounding ground and, if within the prism of construction, shall be compacted There will be no separate payment for backfilling and compaction the resulting cavities

removed, their custody, preservation, and storage on the right-of-way or any

other locations as may be designated by the Engineer or the Employer, or disposal as provided herein

2.2 Removal of Drainage Structures

(a) Bridges, culverts and other drainage structures in use by traffic shall not be removed until satisfactory arrangements have been made to accommodate traffic

(b) The removal of existing culverts within embankment areas will be required only as necessary for the installation of new structures Abandoned culverts shall be broken down, crushed and sealed or plugged

(c) All culvert sections removed, which are not designated for stockpiling or relaying, shall become the property of the Contractor and be removed from the project or disposed of in a manner approved by the Engineer

(d) Unless otherwise directed, the substructures of existing structures shall be removed down to the natural stream bottom and those parts outside of the stream shall be removed down to at least 300 mm below natural ground surface

(e) Where portions of the existing structures lie wholly or in part within the limits for a new structure, they shall be removed as necessary to accommodate the construction of the proposed structure Where only a section of the existing structure is to be demolished, the Contractor shall execute this work in such a way as to avoid damage to the section designated to remain All details of the Contractor's proposed working method shall be submitted to the Engineer for approval

removed from the right-of -way

(g) Blasting or other operations necessary for the removal of an existing structure

or obstruction, which may damage new construction, shall be completed prior

to placing the new work, unless otherwise approved by the Engineer

(h) Steel bridges and wood bridges, when specified by the Engineer to be salvaged, shall be carefully dismantled without damage Steel members shall

be match-marked, unless the Engineer waives such match marking All salvaged material shall be stored as requested by the Engineer

(i) Unless waived in writing by the Engineer, all concrete removed that is of suitable size for rip-rap and not needed for such use on the Project, shall be stockpiled at locations designated by the Engineer, for use by the Employer

2.3 Removal of Curbs

into pieces, the size of which shall not exceed 300 mm in any dimension and stockpiled at designated locations on the site for use of the Employer, or otherwise disposed of as directed by the Engineer

damage to existing pavements and curbs which are designated to remain

2.4 Removal of Pavements, Footpaths, etc

(a) Irrespective of thickness, all asphalt or concrete pavements, footpaths, or other hard surfaces designated for removal, shall be broken into pieces, the size of which shall not exceed 300 mm in any dimension and stockpiled at designated locations on the site for use of the Employer, or otherwise disposed of as directed by the Engineer

abutting sections of pavement or structures designated to remain

individual size less than 10 cubic meters or excavation of ballast, gravel or similar sub-base or base material is necessary, this work shall be considered

as Common Excavation, and shall conform to the requirements of Specification “Common Excavation”, for construction, measurement and payment

2.5 Removal of Traffic Signs

(a) Where directed, traffic signs including steel frames shall be carefully dismantled, removed and stored where directed by the Engineer

(b) Concrete foundations shall be broken into pieces removed and stockpiled at designated locations on the site for use of the Employer or shall be otherwise disposed of as directed by the Engineer

2.6 Removal of Buildings and Structures

(a) Upon receipt of notification by the Engineer, the Contractor shall take over all responsibility for the building or buildings then acquired and vacant and shall proceed with the removal thereof as specified

Contractor shall complete the demolition and removal of buildings and structures together with all foundations and retaining walls, piers, partitions and columns down to a plane 30 centimetres below the ultimate grade in the area

(c) Walls shall be broken into pieces not exceeding 60 square centimetres for any area of surface, mixed with previous backfill material and placed in basement areas

60 square centimetres for any area of surface and shall be left in place Excess debris shall be removed and disposed All other foundations, concrete floor slabs, sidewalks, signs, sheds, garages and fences and all other incidental and collateral work necessary to fully complete the removal of the buildings and appurtenances shall be removed and disposed

himself the work involved and the equipment and the materials required for such demolition work

(f) The Contractor shall arrange for the discontinuance of all utility services that serve the building or buildings in accordance with the respective requirements and regulations of the appropriate government agencies, and the utility agencies involved

the local government agency or agencies responsible and the Engineer, all sewer outlets that serve any building or buildings that the Contractor is directed to remove

(h) The Contractor shall keep the Engineer informed of his plans for the performance of any work in connection with the sealing off of such outlets in order that proper inspection may be provided at the time the work is performed

(i) The Contractor shall conduct his operations in such a manner as to avoid hazards to persons and vehicles After work is started on any building, the work on that building shall be continued to completion, promptly and expeditiously

The area shall then be filled with previous backfill material simultaneously with the breaking of the foundation walls so that the previous backfill material will be well integrated with the pieces of broken concrete

(k) Concrete slabs resting on earth and forming walks, driveways, or the first floor slabs of buildings without basements except as indicated on the Drawings shall be broken up and removed from the site

buildings or miscellaneous structures which have not been indicated on the Drawings

(m) Existing underground storage tanks on the site or within the buildings shall be removed and disposed by the Contractor The Contractor shall take all necessary precautions during the removal of the fluid within the tanks and the removal of the existing tanks Where tanks are removed, the Contractor shall backfill with fine aggregate This backfill shall be in accordance with this Specification section 3.2 “Structural Excavation”

(n) Structures designated to become the property of the Contractor shall be removed from the right-of-way

which may damage new construction, shall be completed prior to placing the new work, unless otherwise provided in the Contract

3 MEASUREMENT AND PAYMENT

Demolition and removal of existing structures and obstructions shall not be measured for payment and shall be included in the pay item of Site Clearing

Demolition and removal of pavement, regardless of its nature (asphalt, concrete, etc.) under this Specification section is applicable only when pavement removal is required in conjunction with site clearing

SECTION 2.3 - DIVERSION AND PROTECTION

OF EXISTING UTILITIES

TABLE OF CONTENTS

1 DESCRIPTION 12

2 CONSTRUCTION REQUIREMENTS 12

2.1 General 12

2.2 Drawings and Documents 13

2.3 Standards, Specifications and Codes 13

3 MEASUREMENT AND PAYMENT 13

3.1 Method of Measurement 13

3.2 Basis of Payment 13

SECTION 2.3 - DIVERSION AND PROTECTION

If these works are requested by the Engineer, the Contractor must be selected and contracted with a professional subcontractor and submit to the Owner for reviewing and approving to carry out these works to confirm with technical and quality requirements

This specification section shall be updated and revised by a professional company

to appropriate with special technical requirements

2 CONSTRUCTION REQUIREMENTS

2.1 G ENERAL

The scope of this work incl udes the supply and delivery to the Site, installation, testing and commissioning as required of all materials, equipment and labor for the actual replacement, relocation, diversion or protection of the following:

(k) Other utilities as directed by the Engineer or the Employer, along with the

associated civil engineering works, all to the extent and in accordance with the Drawings, Standards and Specifications for the installations issued by the Vietnam Utility Authorities namely:

underground installations, 220/380V low voltage distribution overhead lines and power substations

underground cables

2.2 D RAWINGS AND D OCUMENTS

The Contractor shall refer to all relevant drawings issued by the Authorized Agencies to ascertain for himself the relocation of routes of all utility services so as

to maintain adequate clearance between the services The supplied drawings will usually indicate the general arrangement of the works, and the Contractor shall provide working drawings showing the exact routes of all pipes, overhead and underground installations, the exact run of conduits and trunk-connection, the location of manholes or control holes, draw-in and junction units, the number and size of cables in each conduit, etc

2.3 S TANDARDS , S PECIFICATIONS AND C ODES

The Provincial Utility Authorities will provide the following if required:

 Materials Specifications

 Codes, Standards, Construction Practices

 As built drawings Local Government shall provide these above documents (if need )

3 MEASUREMENT AND PAYMENT

3.1 M ETHOD OF M EASUREMENT

For each utility to be replaced, relocated, diverted or protected, the extent of work and the method of measurement will be established by the Engineer in accordance with the requirements of the work as directed by the Employer and the actual work carried out by the Provincial Utility Authorities or by the Contractor

3.2 B ASIS OF P AYMENT

The work, measured as specified above, where applicable, will be valued for payment in accordance with its pertinent clause of “Provisional Sums” included in the Conditions of Contract

Pay Item Description Unit

DIVISION 3

EARTH WORKS

DIVISION 3 – EARTH WORKS

TABLE OF CONTENTS

SECTION 3.1 – COMMON EXCAVATION 1

1 DESCRIPTION 1

2 CLASSIFICATION OF EXCAVATION 1

3 CONSTRUCTION REQUIREMENTS 3

4 MEASUREMENT AND PAYMENT 5

SECTION 3.2 - STRUCTURAL EXCAVATION 6

1 DESCRIPTION 6

2 CONSTRUCTION REQUIREMENTS 7

3 MEASUREMENT AND PAYMENT 12

SECTION 3.3 – NOT APPLICABLE 14

SECTION 3.4 - NOT APPLICABLE 15

SECTION 3.5 - EMBANKMENT CONSTRUCTION 16

1 DESCRIPTION 16

2 MATERIAL REQUIREMENTS 16

3 CONSTRUCTION REQUIREMENTS 19

4 GEOTEXTILE SPREADING PROCEDURES 23

5 MEASUREMENT AND PAYMENT 24

SECTION 3.6 – AGGREGATE SUBBASE AND BASE 26

6 MEASUREMENT AND PAYMENT 35

SECTION 3.7 - SOFT SOIL IMPROVEMENT 37

1 DESCRIPTION 37

2 MATERIAL REQUIREMENTS 39

3 CONSTRUCTION REQUIREMENTS 46

4 MEASUREMENT AND PAYMENT 61

SECTION 3.8 – SCARIFICATION AND REPAIRING EXISTING PAVEMENT 64

1 DESCRIPTION 64

2 CONSTRUCTION METHODS 64

3 MEASUREMENT AND PAYMENT 65

SECTION 3.1 – COMMON EXCAVATION

(d) Common Excavation shall include the removal, handling and proper utilization

or disposal of all excavated materials, regardless of their nature or existing condition, and shaping of excavation and preparation of the exposed surface of excavation in accordance with these specifications and the lines, levels, grades, dimensions and cross-sections shown on the Drawings and/or as required by the Engineer

2 CLASSIFICATION OF EXCAVATION

Common Excavation will be categorized to 3 kinds, such as 1) Soil Excavation, 2) Rock Excavation, and 3) Excavation of Unsuitable Materials

(a) Soil Excavation: Common excavation classified as “Soil Excavation” when

it is composed of the following materials:

 Soil: Roadway excavation classified as soil shall be in accordance with Rock, soil classified tabulation in letter no 1776/BXD-VP dated 16 Aug

2007 of MOC It shall include all soil excavation and soft rock (except for Hard Rock and Boulders herein defined) regardless of its nature or existing condition

 Soft Rock: Soft rock shall comprise weathered rock, sandstone, limestone and such materials which, in the opinion of the Engineer, can be excavated

by picking, ripping or other similar means without resorting to blasting However, Excavation of Unsuitable Materials is treated as different payment item in this Specification as shown in bellow

(b) Rock Excavation: Common excavation will be classified as “Rock

Excavation” when it is composed of the following materials:

 Hard Rock: Roadway excavation classified as hard rock shall include only such roadway excavation that, in the opinion of the Engineer, is not practicable without the use of pneumatic tools or drilling and blasting operations Hard rock shall not include material which, in the opinion of the Engineer, can be loosened or excavated with standard equipment (tractor or backhoe) This soil class includes all the types of rock described in the Vietnamese Standards for soil classification (letter no 1776/BXD-VP dated 16 Aug 2007 of MOC)

 Boulders: Boulders shall comprise solid pieces of rock that are weathered

on all faces and are between 0.25 m3 and 1.0 m3 in volume Boulders will

be measured by the maximum length of the longest axis of the boulder multiplied by the area of the circle with a circumference measured at the widest point of the boulder Boulders with a dimension exceeding the above-stated volume and that cannot be pulverized without the use of pneumatic tools, drilling and blasting operations, or by standard tractor or backhoe, shall be classified as Hard Rock However, boulders that are over the above-stated volume but can be disposed of outside the Project area by using common equipment for transportation without necessity of blasting or pulverization, shall not be considered as rock excavation Boulders that are smaller than the above-stated volume shall be classified

as soil

(c) Excavation of Unsuitable Material: Common excavation will be classified

as “Excavation of Unsuitable Material” when it is composed of:

(1) Materials below the natural ground surface in embankment areas, and in excavation areas below the grading plane or other limits shown in the Drawings, or as designated by the Engineer, that are unsuitable for the planned use

(2) Surplus material over the amount required for the construction of the embankment, provided however that it is not material rendered surplus

by reason of the Contractor having opened borrow pits solely for his own convenience

(3) Materials such as highly organic clays and silts, peat, muck, soil containing a large amount of roots, grass and other vegetal matters, domestic or industrial waste, might be classified as “unsuitable” under this Specification Section

(4) Soils with a liquid limit exceeding 60% and a plasticity index exceeding 35%

(5) Soils with natural water content exceeding 50%

(6) Soil with a very low natural density, 800 kg/m3 or lower

(7) Highly expansive soil having an Activity Value greater than 1.0 or a degree of expansion classified by AASHTO T258 “Standard Method of Test for Determining Expansive Soils” as “Very High” or “Extra High”

The Activity Value shall be measured by the Plasticity Index/Percent Clay Size ratio The application of equivalent ASTM standards is also allowed depending upon the Engineer approval regarding to its proper interpretation and application

(8) Materials having hazardous chemical or physical properties

(9) Soil that cannot be properly compacted in accordance with Specification requirements or as determined by the Engineer

(10) Suitable materials that, in the Engineer’s opinion, were contaminated by unsuitable materials during excavation operations

(11) Material obtained from other work items within the Project area, which quality and/or condition satisfies the requirements for materials of other specification sections, but it is within one of the following categories:

 the total actual and effective distance for its transportation, from the Site location where was obtained to the place where it is intended to

be used, is accepted by the Engineer to be longer than the distance from an approved and operating quarry or borrow pit

 the route for its transportation is passing through existing or temporary roads that are not in practical conditions, and acknowledged by the Engineer to give critical affect to other works

in progress, or to a public road and existing traffic

in the “Schedule of Materials” established in Specification Section 1.15 “Control of Materials”

3 CONSTRUCTION REQUIREMENTS

3.1 Preparation Work

after excavation, and under the supervision by the Engineer, make a topographical survey of the area and submit the surveyed cross section and

profile maps to the Engineer for his consideration and approval to use as a

basis for the computation of the actual volume of excavated materials

(b) Prior to excavation, all necessary clearing and grubbing in that area shall have been performed in accordance with Specification Section 2.1 ”Site Clearing” (c) The Contractor shall include in the “Schedule of Materials”, required by Specification Section 1.15 “Control of Materials”, a detailed plan and schedule for the use of “suitable material” in the Project including details related to the location (of excavation and placement), construction method, time schedule, testing, etc This plan shall be continuously updated, on a weekly basis, in accordance with the progress of the works until completion

of the roadway excavation On the revision of the Plan, the Contractor shall

try to use better materials at the surface or upper course, and comparatively poor materials at the lower places

3.2 Use of Excavated Material

Engineer as “suitable”, shall be used in the formation of the road embankment, subgrade, shoulders, slopes, bedding, surcharge and/or counterweight, backfill for structures, structures, subbase and/or base courses, production of aggregates for concrete or asphalt pavements, or for other purposes shown on the Drawings or as directed by the Engineer

“suitable” for:

 Any other works items shown in the Drawings or as directed by the Engineer

Excavation operations shall be conducted so that material outside the limits of slopes will not be disturbed

for protect slope shall be followed approved drawings and follow requirement

in Specification items 3.5 “Embankment Construction” or as directed by the Engineer

3.3 Dimensional Tolerances

(a) Finished grades, lines and formations after excavation shall not vary from

those specified by more than 20 mm at any point

(b) Finished excavated surfaces that are exposed to surface run-off water shall be sufficiently smooth and uniform, and have sufficient slope, to ensure free drainage of the surface with no pending

4 MEASUREMENT AND PAYMENT

4.1 Method of Measurement

(a) Excavation of Soil and Rock, regardless of the soil nature, existing conditions or geological classification, shall be made measured by cubic meter only in the case where the material has been classified as “unsuitable material” in accordance with this specification

(b) Excavation soil to protect slope and Embankment backfill by fine sand (or other appropriate materials that agreed by the Engineer) at these excavation areas shall

be measured and paid separately as mentioned in Technical Specification item 3.5

“Embankment Construction”

all excavation from the average cross section areas as shown on the design drawings and subsequently deducting the volume of materials for reuse

for any design changes made by the Contractor without the approval of the Engineer or for any material classified as “unsuitable” without the approval of the Engineer

be made for over break or excavation outside the lines, grades and levels in the drawings or subsequently approved by the Engineer

for any material used by the Contractor in his own temporary works

4.2 Basis of Payment

The accepted quantities as Unsuitable Materials, measured as provided above, shall be paid at the contract price per unit of measurement for the pay items of the Bill of Quantities listed below

Payment shall be full compensation for the work detailed in this specification including all preparation, assembly, installation, excavation, removal, ripping, blasting, haulage, placing and compaction for backfilling and reusing or satisfactory disposal of site excavation, for shaping and completion of all surfaces, works for planning and updating, and for furnishing all labour, materials, tools, equipment and any incidentals to complete the work as shown on the Drawings and as required in accordance with these specifications subject to approval by the Engineer

SECTION 3.2 - STRUCTURAL EXCAVATION

in the Specification The use and disposal of all excavated materials shall

be in accordance with these Specification requirements and in conformity with the Drawings, or as directed by the Engineer Any excavation that can

be defined under any other Specification sections will not be considered as Structural Excavation

(c) All excavated material, so far as suitable and approved by the Engineer, shall be utilized as backfill or embankment, or shall be removed from the Site, if exceeding requirements

(d) All surplus material over the requirements shall, if instructed by the Engineer, be considered as waste and treated in accordance with the requirements for “Unsuitable Material (Waste) Excavation” of Specification Section 3.1 “Common Excavation” clause 2.3

(e) Structural Excavation shall include back-filling in accordance with the specifications and approved by the Engineer, incorporating surplus material

in the fill areas in accordance with the requirements of Specification Section 3.5 “Embankment Construction”, hauling and disposing of waste material, and all necessary materials and equipment for keeping the excavation free of surface run-off and groundwater

compacting granular back-fill adjacent to structures The areas in which this material is to be placed shall be as indicated on the drawings or as required by the Engineer

(g) It shall also include the supply and placing of approved foundation fill material to replace unsuitable material encountered below the foundation elevation of structures

(h) This work shall include necessary diversion of live streams, bailing, pumping, draining, sheeting, bracing, necessary construction of cribs and cofferdams, and supply of the materials therefore, and subsequent removal

of cribs, cofferdams and remaining unsuitable material and placing of all necessary backfill

(i) Removal or diversion of existing water flows shall be addressed in accordance with the requirements and stipulations of Specification Section

1.2 “General Works” Sub-Section 2.5.3 “Working in and Dealing with Existing Water Flows”

1.2 Structural Excavation Classification

Structural Excavation is classified for measurement and payment as follows:

(a) Structural Excavation – Opening

Excavation work carry out in dry condition without braced sheet pile cofferdam

(b) Structural Excavation – Dry, in side braced sheet pile cofferdam:

Excavation work carry out in dry condition with braced sheet pile cofferdam

(c) Structural Excavation – Underwater, in side braced sheet pile cofferdam:

Excavation work carry out in underwater condition with braced sheet pile cofferdam

Note: The rate per cubic meter for this item shall be deemed including all required equipment, labor, incidentals, temporary materials and works and costs associated and necessary including, but not necessarily limited to:

(1) all expenses involved in providing pumps, cofferdams (regardless of their type

or material), braced sheet piling or any other methods proposed by the Contractor and approved by the Engineer;

(2) all expenses resulting from the Contractor’s observance of all rules and regulations of competent authorities regarding the interference or maintenance

of flow in the relevant canals, water courses, channels or pipes;

(3) provisions for and driving and removal of sheet piles including providing certification by an Independent Engineer;

(4) provisions for placement and removal of temporary Jetty/Guide frames;

(5) provisions for underwater works;

(6) provisions for underwater concrete, or blinding concrete;

(7) provisions for pumps and dewatering by submersible pumps;

(8) provisions for all necessary barges; and

(9) provisions for all necessary tug boats and auxiliary river craft

2 CONSTRUCTION REQUIREMENTS

2.1 Groundwater

Whenever groundwater is encountered or the excavation is taking place adjacent to free-surface water during structural excavation, the Contractor shall take such measures as necessary under the provisions of Specification Section 1.2 “General

Requirements” Sub-Section 2.5.3 “Working in and Dealing with Existing Water Flows” to ensure that the excavation and footing are kept free of water

2.2 Cofferdams

(a) Suitable and practically watertight cofferdams shall be used wherever bearing strata are encountered above the elevation of the bottom of the excavation

(H10%), an allowance for local and general scour of the river bed and the minimum ship impact requirements as noted in the Drawings showing his proposed method

of cofferdam construction to the Engineer for his approval in accordance with the requirements and stipulations of Specification Section 1.5 “Contractor Drawings” All designs shall be checked by an Independent Professional Engineer, at the Contractor’s expenses, who shall furnish a certification as to the adequacy and safety of the proposed details

(c) Cofferdams or cribs for foundation construction shall be carried out well below the bottom of the footings and shall be well braced and as nearly water-tight as practicable

(d) The interior dimensions of cofferdams shall be such as to give sufficient clearance for the construction of forms and the inspection of their exteriors, and to permit pumping outside the forms

(e) Cofferdams or cribs that are tilted or moved laterally during the process of sinking shall be righted or enlarged so as to provide the necessary clearance

impractical to dewater the foundation before placing the footing, the Engineer may require the construction of a concrete foundation seal of such dimensions as shown on approved shop Drawings The foundation shall then be dewatered and the footing placed When weighted cribs are employed and the weight is utilized

to overcome partially the hydrostatic pressure acting against the bottom of the foundation seal, special anchorages such as dowels or keys shall be provided to transfer the entire weight of the crib to the foundation seal Where a foundation seal is placed under water, the cofferdam shall be vented or ported at low water level as directed

(g) Cofferdams shall be constructed so as to protect green concrete against damage from sudden rising of the water and to prevent damage to the foundation by erosion No timber or bracing shall be left in cofferdams or cribs, without the approval of the Engineer

shall be done in such a manner as to preclude the possibility of any portion of the concrete materials being carried away Any pumping required during concrete placing, or for a period of at least 24 hours thereafter, shall be done from a suitable pump located outside the concrete forms Pumping for dewatering shall

not commence until the seal has set sufficiently to withstand the hydrostatic pressure

all sheets and braces involved therewith, after the completion of the substructure Removal shall be effected in such a manner as not to disturb or damage any finished work

2.3 Preservation of Channel

Unless otherwise permitted, no excavation shall be made outside caissons, cribs, cofferdams or sheet piles, and the natural stream bed adjacent to the structure shall not be disturbed without the approval of the Engineer If any excavation or dredging is made at the site of the structure before caissons, cribs, or cofferdams are sunk in place, the Contractor shall, after the foundation base has been in place, backfill all such excavations to the original ground surface or stream bed with material satisfactory to the Engineer Material deposited within the stream area from foundation or other excavation or from the filling of cofferdams shall be removed and the stream area free from obstruction

2.4 Excavation

(a) Prior to starting excavation operations in any area, the Contractor shall :

 take steps on his own initiative to regulate the natural drainage of the water flowing on the surface of the ground, to prevent flooding of excavations;

been performed in accordance with these Specifications; and

 notify the Engineer sufficiently in advance of the beginning of any excavation so that cross-sectional elevations and measurements can be taken of the undisturbed ground under the Engineer’ supervision The existing ground adjacent to the structures shall not be disturbed without the permission of the Engineer

(b) Trenches or foundation pits for structures or structure footings shall be of sufficient size to permit the placing of structures or structure footings of the full width and length shown The sides of trenches or pits shall be adequately supported at all times The elevations of the bottoms of footings as shown on the Drawings shall be considered as approximate only and the Engineer may order, in writing, such changes in dimensions or elevations of footings as may be deemed necessary to secure a satisfactory foundation

shall be removed from the site and shall not be used for back-filling purposes (d) After each excavation has been completed, the Contractor shall notify the Engineer to that effect, and no footing or bedding material shall be placed

until the Engineer has approved the depth of excavation and the character of the foundation material

(e) All rock or other hard foundation material shall be cleaned of all loose material and cut to a firm surface, either level, stepped or serrated as directed

by the Engineer All seams or crevices shall be cleaned out and grouted All loose and disintegrated rock and thin strata shall be removed

grade shall not be made until just before the footing is to be placed Where the foundation material is soft or mucky or otherwise unsuitable, in the opinion of the Engineer, the Contractor shall remove the unsuitable material and replace it with granular backfill as required by the Engineer This foundation fill shall be placed and properly compacted in 15cm layers up to the foundation elevation

(g) If, in the opinion of the Engineer, the foundation material is unsuitable solely because of the Contractor’s failure to fulfill his obligations under Specification Section 1.2 “General Requirements” Sub-Section 2.5.3

“Working in and Dealing with Existing Water Flows”, then the Contractor may either:

 carry out at his own expense the removal and replacement described above; or

 suspend works in that excavation, at his own expense (without time extension), until such time as the foundation material becomes suitable (h) Where foundation piles are used, the excavation of each pit shall be completed before pile driving and any placing of blinding stone shall be done after the piles have been driven However if for any reason it is impossible to drive the piles after excavation, piles shall be driven from the natural ground level, as directed by the Engineer Surplus length of piles in this case will not

be measured for payment

displaced material shall be removed, leaving a smooth, solid bed to receive the footing

(j) Where a box culvert is to be located in embankment, the Engineer may instruct that the excavation shall be performed after the embankment has been constructed to the proposed sub-grade level and compacted sufficiently

2.5 Backfilling

On completion of the structure, excavated areas shall be back-filled with approved

material to the level of the finished ground surface

2.5.1 Soil Backfilling

Back-fill shall be checked and tested in layers not exceeding 30 cm and compacted

to 95% of the maximum dry density determined according to 22TCN 333-06

2.5.2 Granular Backfilling

Granular backfilling is especially required for specific structures of abutment, retaining wall and others as shown on the Drawings or as indicated by the Engineer Granular backfill shall be checked and tested in layers not exceeding 15 cm and compacted to 95% (for K95) or 98% (for K98) of the maximum dry density determined according to 22TCN 333-06

The material shall be well-graded crushed or uncrushed gravel, stone, rock-fill or natural sand or a well-mixed combination of any of these Grading requirements for Granular Backfill are as follows:

Grading requirements for Granular Backfill

(a) Blinding stone for use as foundation for structures shall be provided as shown

on the Drawings or as instructed by the Engineer

crushed rock, of the maximum size compatible with the thickness of the blinding stone as shown on the Drawings The minimum height of any stone

as placed shall be 7 cm Stone shall be closely packed by hand placing, to the dimensions shown on the Drawings, and then thoroughly rammed by mechanical rammer Smaller stone pieces of a minimum size of 3 cm shall then be placed between the larger stones and the upper surface brought up to the finished level shown on the Drawings or instructed by the Engineer The complete surface shall then be thoroughly compacted to the satisfaction of the Engineer using a mechanical rammer or vibrating roller

use of graded, crushed stone of a maximum size less than 5 cm The

Engineer’s acceptance of this alternative and the maximum thickness to be laid in one layer will depend on the proposed compacting plan and its suitability for the restricted working area available

3 MEASUREMENT AND PAYMENT

3.1 Method of Measurement

(a) Structural excavation shall be measured as the number of cubic meters of material measured in its original position after the completion of clearing and grubbing and the removal of topsoil

(b) Where Contract Drawings require excavation in excess of the size of the structural member, such as for culverts requiring granular backfill, the net horizontal plan area shall be that required for the complete works as detailed on the drawings (c) Unless otherwise specifically approved by the Engineer or as required for the placing of granular material or blinding stone, measurement for structural excavation shall not include any material removed from below the footing grade, from beyond the specified limits of excavation, or material considered to compensate for anticipated swell or as a result of effective swell during pile driving

or additional material resulting from slides, slips, cave-ins, silting or filling

(d) Where excavation after the embankment has been placed has been carried out with the approval of the Engineer, such excavation in the embankment shall be measured for payment as structural excavation

(e) The volume of granular material and blinding stone measured for payment shall be the number of cubic meters of material completed in accordance with this specification and calculated using the nominal dimensions shown on the drawings

or as approved by the Engineer Materials placed in excess of the requirements and dimensions given on the drawings or as required by the Engineer shall not be measured for payment

(f) All granular material required as a consequence of the Contractor’s method of working or due to his convenience shall be placed and compacted at the Contractor’s expense

(g) All requirements for dealing with water flows shall be deemed included in the rates and unit prices for structural excavation and shall include all necessary provisions for dealing with ground water

3.2 Basis of Payment

The accepted quantities, measured as provided above, shall be paid at the contract price per unit of measurement for the pay items of the Bill of Quantities listed below

Payment shall be full compensation for the work prescribed in this Section including all preparation, assembly, installation, excavation, removal, ripping, blasting, haulage, placing and compaction for backfilling and reusing or

satisfactory disposal (waste) of site excavation, for shaping and completion of all surfaces, works for planning and updating, and for furnishing all labor, materials, tools, equipment and any incidentals to complete the work as shown on the Drawings and as required in accordance with these Specifications and/or as directed

SECTION 3.3 – NOT APPLICABLE

SECTION 3.4 - NOT APPLICABLE

SECTION 3.5 - EMBANKMENT CONSTRUCTION

1 DESCRIPTION

This Specification section describes requirements and procedures for the construction of the roadway embankment by placing and compacting all materials obtained from roadway excavation, borrow or channel and structural excavation in accordance with these specification requirements and in conformity with the lines, grades, and dimensions shown on the Drawings or established by the Engineer and accordance with TCVN 9436:1012, Highway Embankment - Standard for construction and acceptance

2 MATERIAL REQUIREMENTS

2.1 EMBANKMENT AND SUBGRADE

The term "subgrade" in embankment construction shall refer to the top layer of the embankment immediately underlying the pavement structure, with 500 mm thickness as indicated on the Drawings or directed by the Engineer The provisions

of these Specifications applicable to "embankment" shall generally apply to subgrade in addition to those provisions especially applicable to subgrade

Embankment and Subgrade shall be constructed of borrow materials, excavated earth or rock or other materials, approved by the Engineer as suitable for use in the permanent work

Trees, stumps, grass or other inappropriate materials shall not be left in the embankment Vegetation layer in embankment must be wiped completely by bulldozer or grader until the grass roots

The exploitation of the fill material must comply with the requirements of environmental protection and natural landscape The exploitation of the backfill material must be combined with local land planning and drainage planning, minimizing the occupied lands; leverage weathered barren; do not take the soil below the underground water; soil dig must be not affected the stability of the slope and the stability of the whole embankment; do not obtain the soil on either side of approach bridge

When existing ground with crossfall less than 20%, the contractor has to excavate and remove organic soil and make ground compaction with K = 0.9 before placing embankment layers

When existing ground with crossfall from 20% to 50%, the contractor has to make step excavation and remove organic soil before backfill Step excavation has to bigger than 2m, step height should be taken by multiples of compacted soil layer

thickness according to available rollers Step surface must be satisfactory compacted and has inward slope with minimum of 2%

The contractor has to take care of water in the boundary surface between the existing ground and embankment layer when carry out slope embankment

Do not carry out embankment on existing ground with horizontal slope more than 50% (without any kind of supporting system)

When existing ground has holes or hollows, the contractor has to clean these holes and backfill with appropriate materials and carry out layer by layer with requirement compaction density

With the embankment through rice area, the contractor must dig out all organic soil layers and pump water out before carry out the work

Materials will also be selected preferentially in accordance with AASHTO designation M57-80 (2000) to exclude the use of highly plastic clay soils, classified

as A-7-6 by AASHTO specification M145

Highly expansive (cracking) soils having an Activity Value greater than 1.25 or a degree of expansion classified by AASHTO T258-81 (2000) as "High" and

"Marginal" shall not be used as embankment fill The Activity Value shall be measured as the ratio of Plasticity Index (AASHTO T90) / Percent Clay Sizes (AASHTO T88)

Rock material shall not be used as backfill around pipes nor in the 30 cm of fill directly beneath subgrade For backfill and fill material used in these locations the maximum stone size shall not exceed 10 cm

The particular requirements for Common Embankment and Subgrade shall be as follows:

- CBR strength: Minimum soaked CBR of 5% (saturated in 4 days) in

accordance with 22 TCN 333-06 – Method I-A

Materials for embankment material can be extracted from mines or materials are identified as appropriate from soil excavation, if testing results show that they meet the requirements for each kind of material below

Materials for cohesive cover layer can be extracted from soil excavation within road area, structural area or can be extracted within 10m of land acquisition boundary Quality of this material shall be in accordance with below requirement of this Specification

2.2 MATERIALS FOR COMMON EMBANKMENT AND SURGRADE

2.2.1 SAND

Sand material used for common embankment K95 and/or subgrade K98 shall comply with the following requirements:

(a) Finer sand, river sand with gradation satisfy the requirement showed in

AASHTO M145-91 (2004), group A3 as follow:

+ Material finer than 0.425 mm sieve: 51% minimum

+ Material finer than 0.075 mm sieve: 10% maximum

+ Clay and organic content: 4% maximum

(b) CBR strength: Minimum soaked CBR of 5% (saturated in 4 days, K≥0,95 of

maximum dry density in accordance with 22 TCN 333-06 – Method I-A) (c) Plasticity: Material shall be non-plastic and free from clay lumps

Sand embankment and sand subgrade shall have a Cohesive Cover Layer

Sand material shall be taken sample and tested for each 500m3 that delivery to site

2.2.2 SOIL (if get approved for using in this project)

(a) For embankment: shall be satisfied these below requirements:

Liquid limit: lower than 40 (≤ 40) Plastic Index: lower than 17 (≤ 17) CBR (saturated in 4 days): more than 5 (≥ 5) K≥0,95 of maximum dry density

in accordance with 22 TCN 333-06 – Method I-A) Maximum diameter: 90 mm

(b) For subgrade: shall be satisfied these below requirements:

Liquid limit: lower than 40 (≤ 40) Plastic Index: lower than 17 ( ≤ 17) CBR (saturated in 4 days): more than 8 (≥ 8) K≥0,98 of maximum dry density

in accordance with 22 TCN 333-06 – Method I-D) Maximum diameter: 90 mm

Materials have a suitable gradation with smooth gradation curve All unsuitable rubbishes, organic…must be removed

Soil material shall be taken sample and tested for each 500m3 that delivery to site

2.3 COHESIVE COVER LAYER

Cohesive Cover Layer, shall be well graded gravelly or sandy clay, or clay and meet K≥0,95 of maximum dry density (accordance with 22 TCN 333-06 – Method I) Cohesive Cover Layer reuse exiting soil shall meet below requirement:

(a) Plasticity Index: 17%  Ip  35% in accordance with AASHTO T90