7 3 ok CW2C ABUTMENT AND PIER

Test method for determination of fineness TCVN 4031-85 Cements - Method for determination of standard workability setting time and volume stabilityTCVN 4032-85 Cements - Methods for dete

CONSTRUCTION METHOD STATEMENT FOR

ABUTMENTS AND PIERS

TABLE OF CONTENTS

CHAPTER I: PREPARATION WORKS

I ARRANGEMENT OF WORKING TEAMS

II MOBILIZATION OF EQUIPMENT FOR CONSTRUCTION OF ABUTMENTS AND PIERS

CHAPTER II: CONCRETE WORK, REINFORCEMENT, FORMWORK

I REFERENCE STANDARDS

II CEMENTITIOUS MATERIAL

III WATER FOR CONCRETE MIXING AND CURING

IV AGGREGATES

V FORMWORK AND FALSEWORK

VI CONCRETING

VII PRECAST CONCRETE

VIII ACCEPTANCES TEST AND TOLERANCES

CHAPTER III: CONSTRUCTION METHODS FOR ABUTMENTS AND PIERS

I CONSTRUCTION OF FOOTING OF ABUTMENTS AND PIERS

II THE GENERAL REGULATIONS FOR CONCRETE WORKS

CHAPTER I: PREPARATION WORKS

I ARRANGEMENT OF WORKING TEAMS

1 Song Lap Vo bridge

Arranging 05 construction teams:

- Team 1: Construction of bored piles

- Team 2: Construction of abutments, piers

- Team 3: Casting box girder;

- Team 4: Casting super T girders and installation of girders andsuperstructure

- Team 5: Casting, driving RC piles and execution of supporting slab andtransition slab

2 Rach Lap Vo bridge

Arranging 04 construction teams for execution:

- Team 1: Construction of bored piles

- Team 2: Construction of abutments, piers

- Team 3: Casting beams and launching and installation of beams andsuperstructure

- Team 4: Casting, driving RC piles and execution of supporting slab andtransition slab

3 Kenh Rach bridge

Arranging 04 construction teams for execution:

- Team 1: Construction of RC piles

- Team 2: Construction of abutments, piers

- Team 3: Casting beams and launching and installation of beams andthe superstructure

- Team 4: Casting, driving RC piles and execution of supporting slab andtransition slab

4 Rach Ong Hanh bridge

Arranging 04 construction teams for execution:

- Team 1: Construction of RC piles

- Team 2: Construction of abutments, piers

- Team 3: Casting beams and launching and installation of beams andthe superstructure

- Team 4: Casting, driving RC piles and execution of supporting slab andtransition slab

5 Rach Xep Cut bridge

Arranging 04 construction teams for execution:

- Team 1: Construction of bored piles

- Team 2: Construction of abutments, piers

- Team 3: Casting beams and launching and installation of beams andsuperstructure

- Team 4: Casting, driving RC piles and execution of supporting slab andtransition slab

II MOBILIZATION OF EQUIPMENT FOR CONSTRUCTION OF ABUTMENTS AND PIERS

The contractor will mobilize the entire construction equipment andmachinery needed for construction Detailed mobilization as in the understatics table:

Description Unit Quantities Remark s

Bulldozer ≥140CV Nos 2

Excavators 1.25m3 Nos 4

Crawler or Moblie Cranes ≥50T Nos 4

Crawler or Mobile Cranes ≥25T Nos 4

Vibratory hammer Nos 4

Concrete agitators Nos 6

Water pump 60m3/h Nos 8

Welding machine 23kw Nos 6

Generator 200KVA Nos 2

Trucks 10-12 tons Nos 6

Rebar bending and cutting

Description Unit Quantities Remark s

Concrete Mixing Plant Nos 2

Transformer Station Nos 1

Concrete Bucket ≥1m3 Nos 4

Front Loader ≥2,4m3 Nos 2

CHAPTER II: CONCRETE WORK, REINFORCEMENT, FORMWORK

I. REFERENCE STANDARDS

The following Standards in their latest edition shall be particularly applied to theworks covered by this Specification

TCVN 141-08 Portland cement - Methods of chemical analysis

TCVN 5438-04 Cements - Standard Specification for Terminology

and definitionsTCVN 5439-07 Cements - Standard Specification for Classification

TCVN 4029-85 Cements - Technical requirement procedure for

physical contents testingTCVN 4030-03 Cement Test method for determination of fineness

TCVN 4031-85 Cements - Method for determination of standard

workability setting time and volume stabilityTCVN 4032-85 Cements - Methods for determination of bending

and compressive strengthTCVN 4453-95 Concrete & integral Steel concrete structure - Code

of Construction and acceptance standardTCVN 6016-95 Cements - Test methods - Determination of strength

TCVN 6017-95 Cements - Test methods - Determination of setting time

and soundnessTCXDVN 302-04 Water for mixing concrete and mortar – Technical

requirements TCXDVN 305-04 Mass concrete - Code ofConstruction and acceptance procedure AASHTO M6Fine Aggregate for Portland cement Concrete;

AASHTO M33 Preformed Expansion Joint Filler for Concrete

(Bituminous Type)AASHTO M80 Coarse Aggregate for Portland Cement

Concrete; AASHTO M85 Portland Cement;

AASHTO M115 Asphalt for Damp-proofing and Waterproofing;

AASHTO M116 Primer for Use with Asphalt in

Damp-proofing and WaterDamp-proofing;

AASHTO M148 Liquid Membrane-Forming Compounds for Curing Concrete;

AASHTO M153Preformed Sponge Rubber and CorkExpansion Joint Fillers for

Concrete Paving and Structural Construction;

AASHTO T22 Compressive Strength of Cylindrical Concrete Specimens;

AASHTO T23Making and Curing Concrete Test Specimens inthe Field;

AASHTO T96 Resistance to Abrasion of Small Size Coarse Aggregate by

Use of the Los Angeles Machine;

AASHTO T119 Slump of Portland cement Concrete;

AASHTO T121 Mass per Cubic Meter, Yield, and Air Content (Gravimetric)

of Concrete;

AASHTO T141 Sampling Freshly Mixed Concrete;

AASHTO T224 Correction for Coarse Particles in the Soil Compaction Test;

ACI 347Guide to Formwork for Concrete, American ConcreteInstitute -

ACI Committee 347ASTM C31 Making and Curing Concrete Test Specimens in the

Field; ASTM C33Concrete Aggregates;

ASTM C39 Compressive Strength of Cylindrical Concrete

Specimens; ASTM C40Organic Impurities in FineAggregates for Concrete;

ASTM C87 Effect of Organic Impurities in Fine Aggregate on Strength

of Mortar;

ASTM C88 Soundness of Aggregate by Use of Sodium Sulphate

or Magnesium SulphateASTM C94 Standard Specification for Ready-Mixed Concrete;

ASTM C109 Compressive Strength of Hydraulic Cement Mortars (Using

2-in or 50-mm Cube Specimens);

ASTM C123 Lightweight Pieces in Aggregate;

ASTM C136 Sieve Analysis of Fine and Coarse Aggregates;

ASTM C138 Unit Weight, Yield, and Air Content (Gravimetric) of

Concrete; ASTM C143Slump of Portland Cement Concrete;ASTM C144 Aggregate for Masonry Mortar;

ASTM C150Portland Cement;

ASTM C227 Potential Alkali Reactivity of Cement-Aggregate

Combinations (Mortar-Bar Method);

ASTM C294 Constituents of Natural Mineral Aggregates;

ASTM C295 Petrography Examination of Aggregate for

Concrete; ASTM C494Chemical Admixtures forConcrete;

ASTM C827 Change in Height at Early Ages of Cylindrical Specimens

II. CEMENTITIOUS MATERIAL

Cement shall be Portland cement type I complying in all respects with ASTMC150 (AASHTO M85) or Portland cement blend complying in all respects withASTM C1157-GU However the Contractor may submit to the Engineer for hisapproval fully supported proposals for the use of other types of cement Allcement shall be manufacturer’s standard cement unless otherwise specified onthe drawings Only one brand of cement shall be used for all concrete worksthroughout the Project unless otherwise authorized by the Engineer

Cement shall be delivered to the Site in sealed bags or in bulk The Contractorproposed source of supply of cement shall be submitted to the Engineer for hisapproval All deliveries of cement to site shall include appropriate testcertificates, certified by an independent agency in the country of origin,confirming that the material delivered complies with the specification

Bagged cement shall bear the manufacturer’s name, cement type and the date

of manufacture and shall be stored in waterproof sheds or other such temporarybuildings used exclusively for the storage of cement Cement shall be stored indry conditions on areas raised above ground level Storage capacity shall besufficient to hold enough cement for the largest units to be cast Bags shall not

be stored more than 8 high and a free passage of at least one meter shall be leftbetween the cement and the side walls of the sheds

Cement delivered by bulk carriers shall be stored in silos made for cementstorage All handling shall be by methods that prevent contamination of thecement The silos shall be provided with interior moisture control devices thatkeep the cement dry and prevent premature hydration The silos shall beprovided with access ladders and access points to enable samples to be takenfrom various levels of each silo for testing purposes

Access ways shall be provided between storage containers such that everycontainer can be visually inspected Each delivery shall be stored separatelyfrom previous deliveries Deliveries shall be used in the order in which they weredelivered Any delivery which has become caked or otherwise adversely affectedshall be removed from the Site at the Contractor’s expense

The Contractor shall provide weighing machines which shall be keptpermanently in each shed for checking the weight of the bags

III. WATER FOR CONCRETE MIXING AND CURING

The Contractor’s proposed water source shall be submitted to the Engineer forhis approval together with test results confirming that water from the sourcecomplies with TCXDVN-302-2004 Periodic testing of the water source shall bemade at least monthly

Water for concrete mixes, curing concrete and other products containing cementshall be clean water free from oil, salt, acid, sugar, vegetable or any othersubstance injurious to the concrete unless otherwise authorized by the Engineer

IV. AGGREGATES

Aggregates shall be free of substances that react deleteriously with alkali in thecement sufficiently to cause unacceptable expansion of the concrete TheEngineer’s approval of aggregate sources will be based on satisfactory evidencefurnished by the Contractor that the aggregate is free from such materials Thisevidence shall include certified records of tests by a testing laboratory that theaggregates meet the requirements of ASTM-C227 and may include service

records of concrete of comparable properties placed under similar conditions ofexposure Tests shall be made in accordance with ASTM-C287 and ASTM-C295ASTM C1077.

1 Fine Aggregate

Fine aggregate shall consist of natural sand with hard, strong, durable particles

or other inert materials with similar characteristics Fine aggregate shall beclean and free from extraneous materials, clay balls, organic matter or otherdetrimental material in accordance with AASHTO M6 The maximum combinedquantity of soluble chloride and sulphate in fine aggregate shall not exceed1,000 ppm

Fine aggregate shall be reasonably graded and shall meet the gradingrequirements mentioned in Table 1

Fine aggregate shall be of such uniformity that the fineness modulus as defined

in AASHTO M6 shall not vary more than 0.20 in either way from the finenessmodulus of the representative samples used in the mix designs

Table 1 Grading Requirements of Fine Aggregate

Sieve Size (mm) Percentage Passing by Weight (%)

Coarse aggregate shall be reasonably graded and shall meet the gradingrequirements in Table-2-1 in subsection 3.2 Concrete Classes

The percentage wear of the aggregate shall not be greater than 50 asdetermined by AASHTO-T96 Coarse aggregate shall withstand at least fivecycles of immersion and drying in both sodium sulphate and magnesiumsulphate solutions, as prescribed in the soundness test, and shall show anaverage weight loss of not more than 15 percent

4 APPROVED MIX DESIGN

The Contractor shall follow ACI (American Concrete Institute) method ofconcrete mix design or similar internationally acceptable mix designprocedure The mix design shall include mass of dry aggregates, mass ofabsorbed water in the aggregates and mass of free water per cubic metre ofwet concrete mix Separate concrete mix designs shall be prepared if pozzalonicmaterial such as micro silica, GGBS (ground granulated blast furnace slag),PFA(pulverised fuel ash) is used

In principle the concrete shall be proportioned in order to reliably meet thecriteria for acceptance through use of a target mean strength as follows

Where the standard deviation is not more than

3.5MPa:

Target strength = specified strength + (1.4 standard

deviation) Where the standard deviation is more than 3.5MPa

Target strength = specified strength + (2.4 x standard

During the execution of the Works, the Engineer may require additional tests to

be made on the work mix to check compliance with the approved Mix Design

5 WATER - CEMENT RATIO

Maximum water cement ratio shall be 0.40 for Class C35 and above class ofconcrete The Contractor’s proposed water content and water cement ratioshall be included in the mix designs, supported by trial mixes, submitted tothe Engineer for his approval The water content shall be the least amount thatshall produce a workable homogeneous plastic mixture Excess water shall not

be permitted and any batch containing such excess shall be rejected

The total water content for any batch of concrete shall include an allowancefor water contained in the aggregates The Contractor shall determine thewater content of the aggregates before concrete batching begins andadmixture (if any) The water added to the mix shall be adjusted for the watercontained in the aggregates

Frequent slump tests shall be carried out to ensure that the workability ofthe concrete remains consistent

6 ADJUSTMENTS DURING PROGRESS OF WORK

After a mix design has been approved, the mix shall not be changed during theprogress of the work except as follows:

If it is found impossible to obtain concrete of the desired workability with themix proportions originally determined, changes in aggregate weights may bemade subject to the approval of the Engineer

If it is found impossible to produce concrete of the minimum compressivestrength specified, the cement content may be increased subject to theapproval of the Engineer

7 CONTENTS OF CHLORIDE AND SULPHATE

The amount of chloride in the concrete mass shall not exceed 1,000 ppm of thetotal concrete mass, or 6,000 ppm of the amount of cement in the mix

The amount of sulphate in the concrete shall not exceed 3,500 ppm of the totalconcrete mass to TCVN141:1998

The amounts of chloride and sulphate shall be determined by recognizedmethods of laboratory analyses of the cement, aggregates, water andadmixtures

V. FORMWORK AND FALSEWORK

1 DESIGN

The design shall be appropriate for such temporary works and shall take intofull consideration all temporary loading cases arising from the procedures andwork sequences, the prevailing conditions at the site, in particular likely windloading, and the nature of the existing ground The Contractor shall carry out alladditional soils investigation necessary to confirm his assumptions concerningthe nature of the existing ground Falsework and forms shall provide for the fullcamber and roadway crown specified in the contract documents.

For cast-in-place concrete structures, the calculated deflection of falseworkflexural members shall not exceed 1/240 of their span irrespective of the factthat the deflection may be compensated by camber strips

Formwork and falsework shall be designed for vertical load and lateralpressures in accordance with ACI 347 and, where appropriate, any increased orre-adjusted loading that may result from pre-stressing forces If retardingadmixtures are used, their effect shall be duly considered during thecalculation of the lateral pressures of the fresh concrete The formwork andfalsework shall be designed and constructed to ensure completed concretesurfaces comply with the tolerances specified in ACI 347 or elsewhere in thisspecification

Falsework which cannot be founded on a satisfactory footing shall besupported on piles which shall be spaced, installed, and removed in anappropriate manner

Where required by Vietnamese standards, load testing of falsework /scaffolding shall be carried out to a minimum of 125% of design load

When manufactured formwork, shoring or scaffolding units are used, themanufacturer’s recommendations for allowable loads shall be followed In suchcases the Contractor shall provide certificates and test reports or records ofsuccessful experience Reduced allowable load values may be required formaterials which have or will experience substantial reuse

Where falsework openings are required for maintaining traffic flows or forpedestrian access the Contractor shall provide all necessary additionalfeatures to protect the public and to ensure that the falsework will remainstable, particularly if subject to impact by a vehicle Where openings areprovide the design shall include but not be limited to

 the anchoring of stringers to caps or frames in adjacent spans

 adequate bracing during construction or removal, and

 at least a 300mm gap between the falsework and protective railing

2 CONSTRUCTION OF FORMWORK

The formwork shall be constructed accurately to represent the shape of thestructure as detailed on the drawings It shall be of suitable design andappropriate construction and shall have been approved by the Engineer TheContractor shall make any necessary adjustments to allow for shrinkage,settlement or deflection which may occur during construction so that thefinished concrete sections conform accurately to the specified dimensions true

to line, level, location and camber

Wooden boards shall be cut accurately to shape and fixed such that there are

no openings after the wetting of the formwork prior to placing concrete

All exposed sharp edges and corners shall be chamfered using triangular filletsnot less than 2 cm by 2 cm in size, unless otherwise directed by the Engineer