07 2 iok a1 ABUTMENT AND PIER

CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION CONSTRUCTION METHOD STATEMENT FOR ABUTMENTS AND PIERS TABLE OF CONTENTS CHAPTER I: PREPARATION WORKS I CONSTRUCTION LAYOUT CHAPTER II: FALSEWORK CONCRETE WORK, REINFORCEMENT, FORMWORK, I FORMWORK AND FALSEWORK II REINFORCEMENT III CONCRETE WORK IV INSPECTION AND ACCEPTANCE CHAPTER III: CONSTRUCTION METHODS FOR ABUTMENTS AND PIERS I GENERAL II CONSTRUCTION SEQUENCES FOR ABUTMENTS AND PIERS 1/ 19 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION CHAPTER I: PREPARATION WORKS I CONSTRUCTION LAYOUT The Site of the Contract Package A1 is from Km65+000 (ending point of Contract package 7) to Km81+150 (beginning point of Contract Package A2), total length of the package is of 16,150 meters The Site is located in Phu Ninh district, Tam Ky city and Nui Thanh district of Quang Nam province a Summary of Detailed Design (D/D) Results The summary of D/D results of Package A1 is shown in Table Summary of D/D Results No Items Main Features Quang Nam province: 16.150km 01 Beginning Point: Km65+000, Tam Thai Commune, Phu Ninh District, Quang Nam Province Road Length Ending Point: Km81+150, Binh Quy Commune, Thang Binh District, Quang Nam Province 02 Road Classification Expressway: Type A, Class 120 03 Design Speed Expressway: 120km/hr 04 Nos of Lane lanes (Ultimate stage: Widened to lanes) 05 Road width Expressway: Road 25.5m, Bridges: 25.5m bridges (L=515.8m) 06 Other River Bridge (L100m): bridge (L=280m) Cross Road Flyover : bridges (L=145.8m) 07 Underpass 19 cross roads (Thruway: 19) 08 Culvert 10 Interchange None 11 Frontage Road 1,902 m Culvert Box: 25 (Thruway: 25) Culvert Pipe: 25 (Thruway: 25) The summary of bridge design results in Package A1 is shown in Table Table Summary of Bridge Design Results in Package A1 N o Bridge Code Jurisdiction City/ Provinc e FO06a ORB17a 2/ 19 Quang Nam Distric t Bridge Location Commune Thruwa y Expressway/Linking Road SA/PA Interchange Thruwa Thruw Rampway y ay Design Results Cross Road Bridge Station Km066+455.0 Km066+615.0 D/D Girde r Type PC Void Slab PC-I Girde r Girder Arrange 3@30 1@24 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION LRB12 ORB21 FO07 Nui Thanh Tam Xuan Km068+457.2 Tam Anh Km075+182.2 Km076+970.0 PC-I Girde r PC-I Girde r KFrame 7@40 2@33 12.4+31+12 Construciton Sequence 3/ 19 - Bridge shall be chosen as the place to gather materials and machinery at the positions of apporach roads on the left side , facilitate the movement of machinery or supply equipment - Carry out the demolition works within the construction area of bridge - Leveling of construction site - Construction of the boundary fence around the site by wire mesh - Construction of temporary service roads - Construction of warehouses, accommodation, casting yards - Details of construction plan show in the drawings of construction method for each bridge PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION CHAPTER II: CONCRETE WORK, REINFORCEMENT, FORMWORK, FALSEWORK All specifications for this work item will be in accordance with Division 7: Concrete and Bridge Works of the Specification I FORMWORK AND FALSEWORK The Contractor shall submit a method statement for formwork and falsework, including design calculations, shop drawings, working drawings and details of all materials and manufactured goods included in the formwork and falsework to the Engineer for his approval at least two months before the start of construction work on Site Work shall not start until approval has been given Formwork shall be made of steel to ensure rigidity, stability and removable, and will not cause difficulties for installation of reinforcement steel, placing and compacting concrete Formwork and falsework shall be designed for vertical load and lateral pressures in accordance with Vietnamese Standard TCVN 4453-1995 and where appropriate, any increased or readjusted loading that may result from prestressing forces If retarding admixtures are used their effect shall be duly considered during the calculation of the lateral pressures of the fresh concrete The formwork and falsework shall be designed and constructed to ensure completed concrete surfaces comply with the tolerances specified in Vietnamese Standard TCVN 4453-1995 or relevant Specification All joints in shuttering or moulds must be tight to avoid water loss when poured and compacted cement concrete, at the same time protect the fresh concrete from weather influences Fabricating and installation of formwork must be accurate as in accodance with the correct shape and size Formwork will be the appropriate design and durable construction The contractor will adjust to get the exact concrete structures to ensure small chamfer, camber, etc It is neccessary to limit formwork joints, the joints should not be arranged on the same cross section and at the position of big loads The bracing, strut and supports should be calculated and arranged appropriately to the overall stability of formwork Installation of formwork should ensure the following requirements: 4/ 19  The formwork surface in contact with concrete shall be covered by non-stick oil The anti-adhesive oil is applied according to the manufacturer's instructions and not touch either reinforcing steel or prestressed strand and anchors The Contractor shall use only one type of anti-adhesive oil for the concrete structure to ensure uniformity of color concrete  Formwork will be cleaned thoroughly before pouring concrete  Formwork is installed how to match up with the early removal of formwork without affecting to the quality  Formwork must be placed firmly on concrete or a hard ground, smooth, non-slip and no deformation when the bearing the load and the impact of the construction process PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION  When installation of formwork, the surveying markers, control points or the appropriate measures to check the centre line  Tolerances for installing formwork must be in compliance with project standards Formwork is only be removed when the concrete have reached the strengths of each type of structures indicated by the technical instructions of the project Removal of formwork should be avoided without causing sudden stress or strong collision: 5/ 19 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION F ormwork/Falsework Precast Girder (I) Support members/Pier head (30 MPa) Time / % of Design Strength of Concrete - / 90% - / 100% Centering under girders, beams, frames or arches 14 days / 80% Floor slabs 14 days / 70% Columns days / 70% Walls, sides of beams and all other vertical surfaces day / 70% To enable finishing, forms used for parapets, barriers, and exposed vertical surfaces may be removed between 24 hours and 48 hours after casting, depending on weather conditions II REINFORCEMENT General requirement Reinforcement steel used in reinforced concrete structures must be ensured the design requirements Reinforcement steel is fabricated at the site in conformity with the Specifications Do not use the reinforcement steels of the same shape, geometrical size in the same works, but different physical properties All Reinforcing Steel bars and deformed billet steel shall conform to Vietnamese Standard TCVN 1651:2008 In case items are not covered by TCVN 1651:2008 then AASHTO M31 (ASTM A615), Grade 60 or equivalent and AASHTO M31 (ASTM A615), Grade 40 for plain round reinforcing bars shall be used Testing shall be in accordance with Vietnamese Standard TCVN 1651:2008 with AASHTO T68 as the equivalent standard Unit stress calculations for bars having an area differing by percent or more from the nominal bar area shall be made using the actual measured bar area Before fabrication of reinforcement steel and before placing concrete should ensure:  The surface is clean, no sticky dirt, grease, no flakes and rust layers on steel  Reinforcement in the yard will be placed on sleepers with canvas cover  Reinforcement steel were crushed, loss in cross section due to cleaning or other reasons shall not exceed the permitted limit of 2% in diameter If this limit is exceeded that limit reinforcement steels shall be used in actual remained cross section  Reinforcement steel should be bent, pulled and straightened Cutting and bending of reinforcing steel The fabrication of reinforcing steel is in compliance with project standards 6/ 19 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION Cutting and bending reinforcing steel shall be conducted only by mechanical methods Reinforcing steel is bent to fit the shape, size of the design Steel products to be cut and bent must be inspected and approved by the Engineer Bar reinforcement shall be cut and bent to the shapes shown on the Drawings Fabrication tolerances shall be in accordance with ACI 315 All bars shall be bent cold, unless otherwise permitted Bars partially embedded in concrete shall not be field bent except as shown on the Drawings or as specifically permitted The dimensions of hooks and the diameters of bends measured on the inside of the bar shall be as shown on the Drawings When the dimensions of hooks or the diameter of bends are not shown, they shall be in accordance with Article of Vietnamese Standard 22TCN 272-05 Bridge Design Standard Reinforcement Joints Welding Joints: Welding Joints are permitted only when approved by Consulting Engineer or specified in the drawings Welding joints can be done by several different methods, but to ensure quality of welding seams as in accordance with design requirements When febricating the reinforcing steel grid by welded points, if no special instructions, comply with the following provisions:  For the smooth round steel, welding all the points of intersection  For deformed steel, welding all the points of intersection in two rows of outer perimeters, the remaining points in between by a welding alternating order; Electrical arc welding is used in the following cases:  Welding the extended hot-rolled steel bars with diameter greater than mm  Welding all the in-situ details, the component structures and bonding of joints in the assembly The welding joints must meet the following requirements:  Smooth surface, no uninterrupted fire, no narrow locally and there are no bubbles  Make sure the length and height of welding seams as required design Reinforcing Steel Components Chemical Composition Percent Carbon (C) 0.30 Manganese (MA) 1.50 Carbon Equivalent (CE) 0.55 Lap joint: 7/ 19 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION Lapped splices shall be of the lengths shown on the Drawings If not shown on the Drawings, requirements for lapped slices shall be in accordance with Article 5.10.3 of the Vietnamese Standard 22TCN 272-05 Bridge Design Standard The bars in lapped splices shall be placed and wired in such as manner as to maintain the minimum concrete cover and the minimum spacing between the bars as detailed in the Specification In Lap Joints, tied with steel wire rods that maintain the minimum distance to the surface of the concrete as shown in the drawing Mechanical Joint (Coupler Type) Splices made with mechanical couplers shall be used only if detailed on the Drawings or previously approved by the Engineer in lieu of welding Such couplers shall develop in tension or compression as required, at least 125 percent of the specific yield strength of the bar When requested by the Engineer, up to two field splices out of each 100, or portion thereof, placed in the work and chosen at random by the Engineer, shall be removed by the Contractor and tested to 125 percent of the specified yield strength Tensile failure must be occur in the bar away from the joint There must be no reduction of the nominal cross section area of the parent bar Couplers must be marked to allow full traceability of the material Couplers connecting bar reinforcement embedded in existing structures to other bar reinforcement should meet the performance criteria Mechanical Joint by threaded coupler splice shall be applied to rebar more than D36 Splicing of Mesh or Mats Sheets of mesh or bar mat reinforcement shall be spliced by overlapping sufficiently to maintain a uniform strength and shall be securely fastened at the ends and edges The lap shall not be less than one mesh in width plus 50 mm III CONCRETE WORK General requirement The concrete materials must ensure the technical requirements as specified in the Specifications During the storage, transportation, materials must be stored to avoid contamination or mixed grain sizes and types When encountering such cases, it should be immediately remedied to ensure the stability of quality The Contractor shall submit samples of all materials to be used in concrete mixes together with test results confirming their compliance with this Specification Section for the approval of the Engineer The Contractor shall use approved materials to prepare mix designs and for trial mixes to be approved by the Engineer No materials shall be delivered to the Site until materials, mix designs and trial mixes have been approved by the Engineer 8/ 19 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION Material for concrete 2.1 Portland cement Cement shall be Portland cement (type 1) or Portland blended cement (type 2) as classified in Vietnamese Standard TCVN5439:2004, complying in all respects with Vietnamese Standard TCVN 2682-2009 or TCVN 6260-2009 However the Contractor may submit to the Engineer for his approval fully supported proposals for the use of other types of cement whose tests comply with Vietnamese Standards: TCVN4029:1985, TCVN 4030:2003, TCVN4031:1985, TCVN4032:1985, TCVN6016:1995 and TCVN6017:1995 All cement shall be manufacturer’s standard cement unless otherwise specified on the Drawings Only one brand of cement shall be used for all concrete works throughout the Works unless otherwise authorized by the Engineer Cement shall be delivered to the Site in sealed bags or in bulk The Contractor proposed source of supply of cement shall be submitted to the Engineer for his approval All deliveries of cement to Site shall include appropriate test certificates, 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 temporary buildings used exclusively for the storage of cement Cement shall be stored in dry conditions on areas raised above ground level Storage capacity shall be sufficient to hold enough cement for the largest units to be cast Bags shall not be stored more than high and a free passage of at least one meter shall be left between the cement and the side walls of the sheds Cement delivered by bulk carriers shall be stored in silos made for cement storage All handling shall be by methods that prevent contamination of the cement The silos shall be provided with interior moisture control devices that keep the cement dry and prevent premature hydration The silos shall be provided with access ladders and access points to enable samples to be taken from various levels of each silo for testing purposes Access ways shall be provided between storage containers such that every container can be visually inspected Each delivery shall be stored separately from previous deliveries Deliveries shall be used in the order in which they were delivered Any delivery which has become caked or otherwise adversely affected shall be removed from the Site at the Contractor’s expense The Contractor shall provide weighing machines which shall be kept permanently in each shed for checking the weight of the bags 2.2 Water for Concrete Mixing and Curing The Contractor’s proposed water source shall be submitted to the Engineer for his approval together with test results confirming that water from the source complies with this Specification Section Water for concrete mixes, curing concrete and other products containing cement shall be clean water free from oil, salt, acid, sugar, vegetable or any other substance injurious to the concrete in according with Vietnamese Standard TCVN 4506:2012 9/ 19 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION 2.3 Aggregates Aggregates shall be free of substances that react deleteriously with alkali in the cement sufficiently to cause unacceptable expansion of the concrete The Engineer’s approval of aggregate sources will be based on satisfactory evidence furnished by the Contractor that the aggregate is free from such materials This evidence shall include certified records of tests by a testing laboratory that the aggregates meet the requirements of Vietnamese Standard TCVN 7570:2006 and may include service records of concrete of comparable properties placed under similar conditions of exposure Tests shall be made in accordance with Vietnamese Standard TCVN 7572:2006 All aggregates shall consist of tough, hard, durable uncoated particles The Contractor shall be responsible for processing aggregates to meet the requirements of this Specification Section The Contractor’s proposed sources of aggregates shall be submitted to the Engineer for his approval Samples shall be taken in the presence of a representative of the Engineer and the Contractor for testing and approval before materials are brought to the Site Aggregates shall be stored in stockpiles that ensure the materials remain free draining and are adequately separated to prevent cross contamination Stockpiles shall be placed on a properly prepared surface to ensure no contamination occurs when materials are re-handled Materials shall be handled in a manner which avoids segregation All stockpiles are to be labeled with markers indicating the material type in the stockpile Materials previously approved but rendered unacceptable due to inadequate storage or handling will be rejected Aggregates shall be stored in sufficient quantity to ensure that there is no interruption of concreting work at any time Aggregates shall be stored near the mixing plant and shall be checked and approved by the Engineer prior to use by the Contractor Fine and coarse aggregates shall be tested in accordance with Vietnamese Standard TCVN 7572:06 Source approval shall be withdrawn if aggregates not meet the requirements of this Specification Section during routine testing Fine aggregates Fine aggregate shall consist of natural sand with hard, strong, durable particles or other inert materials with similar characteristics Fine aggregate shall be clean and free from extraneous materials, clay balls, organic matter or other detrimental material in accordance with Vietnamese Standard TCVN 7570:06 Fine aggregate shall be reasonably graded and shall meet the grading requirements as in the Specifications Fine aggregate shall be of such uniformity that the fineness modulus as defined in Vietnamese Standard TCVN 7570:06 shall not vary more than 0.20 in either way from the fineness modulus of the representative samples used in the mix designs Coarse aggregate Coarse aggregate can be provided under the form of blend of many particle sizes or separate particle sizes The gradation of coarse aggregate, shown by quantity of accumulated residuary on the meshes, is mentioned in Table 10/ 19 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION Grading Requirements of Coarse Aggregate Sieve Size mm Quantity of accumulated residuary on the Sieve, % quantity, corresponding with the smallest particle size and biggest particle size, mm 5-10 5-20 5-40 100 5-70 10-40 70 40 10-70 20-70 0 0-10 0-10 0-10 0-10 40-70 0-10 40-70 40-70 40-70 20 0-10 10 0-10 40-70 90 100 90 100 40-70 90-100 90-100 90-100 90-100 90-100 TCVN 7570:2006 Content of silt, dust, clay in the coarse aggregate depends on the concrete grade which shall not exceeded the values in Table Content of silt, dust and clay in the coarse aggregate Concrete compressive strength > 30MPa From 15MPa 30MPa < 15MPa Content of silt, dust and clay, % quantity, not greater than 1,0 to 2,0 3,0 The compressive strength of rock used for coarse aggregate in concrete shall be ascertained from the original rock sample or shall be determined through press test inside the cylinder In the latter case (1) igneous and metamorphic rock shall have a compressive strength times higher than compressive strength of the concrete and (2) sedimentary rock shall have a compressive strength 1.5 times higher than the compressive strength of the concrete The wearability of coarse aggregate when impacting is tested by the Los Angeles machine, it is not greater than 50 % of quantity Content of flat particle in the coarse aggregate shall not exceed 15% for concrete compressive strength > 30MPa and shall not exceed 35% for concrete compressive strength