CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION METHOD STATEMENT FOR ROAD WORKS TABLE OF CONTENTS I SITE CLEARING, GRUBBING, EXCAVATION TOP SOIL II EXCAVATION III ROCK BLASTING IV EMBANKMENT V CONSTRUCTION SUB - BASE AND BASE COURSE VI CONSTRUCTION ASPHALT CONCRETE PAVEMENT, ASPHALT TREATED BASE COURSE VII CEMENT TREATED BASE COURSE VIII PORTLAND CEMENT CONCRETE PAVEMENT IX BITUMINOUS SURFACE TREATMENT 1/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION CHAPTER I: METHOD STATEMENT FOR ROAD I Site Clearing, grubbing, excavation top soil Site clearing, grubbing, excavation top soil Site clearance and grubbing: This work shall include the removal from ground surface and grubbing of root and miscellaneous foundation of all dense vegetation, bushes, trees, hedges, debris, rubbish, fence, obstructions and the like together with the removal and disposal off the Site, of all materials and waste arising therefore, all as indicated on the drawings or as instructed by the Engineer and as specified The waste material and disposal and unsuitable materials shall be disposed by dump trucks to dispose site The suitable material to be reused under Engineer’s instruction shall be stored and protected separately by Bidder The quantity of clearing and grubbing for payment shall be the actual completed area approved by the Engineer upon completion The construction sequence is as follows: +Step 1: Site is cleared be bulldozer and labor +Step 2: The top soil is excavated and removed by excavator +Step 3: The excavated top soil shall be removed and dumped in dumps and leveled by bulldozer +Step 4: The waste and unsuitable materials shall be loaded on the dump truck and then transported to the disposal site Demolition and removing existing structures 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 cubic meter, of all buildings, hedges, fences, structures, pavements regardless of its nature (asphalt, concrete, etc.), 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 Bidder shall schedule the work associated with Specification 2/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION II Excavation General This section bidder presents method statement for excavation, this work include supports to the sides or additional excavation to form sloped sides, working space, keeping the excavations free of all water (including surface water and ground water), segregation of material suitable for backfilling or embankments, all necessary handling, stockpiling, disposal, shaping and trimming completed excavations in accordance with the locations, lines, levels, grades and dimensions shown on the Drawings and as specified herein This work also includes general over site excavation to reduce levels, excavation in and the necessary diversion of or containment of canals and water courses; including all necessary pumping, draining, sheeting, bracing and the construction, maintenance and subsequent removal of cribs and cofferdams Method statement 2.1 Preparation 2.1.1 Machine and labor Machine and personnel construction are fully prepared by Bidders to ensure quality and quantity Prior to construction, the Bidder will trial operation of machinery and equipment to ensure all the equipment stable operation during construction 2.1.2 Preparation construction site Prior to the construction of the excavation bidder conducting the cleanup, grass, tree, stripping of top soil and cleaning obstacles within the construction site Ensure drainage construction sites 2.1.3 Disposal Prior to construction, the Bidder will test expected disposal field position to ensure that the disposal work is not cause negative impact to environment, local planning as well as the effects the stability of the roadbed itself 2.2 Detail method statement Road excavation shall not start until topsoil has been removed from the work area Based on the plans and drawings the Bidder shall proceed the survey and setting out for the construction limits, submit the daily requests for inspection of work to the Engineer Based on the topographic conditions of the package, type of cross-section excavation, the length and direction of excavated transport , the roadway shall 3/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION be excavated by Bulldozer, excavator in combination with manual and transport by dump truck in accordance with the level, line, dimensions, cross section shown on the Drawing /or as required by the Engineer In the case the thickness of ground to be excavated and removed is bigger than design thickness, our Bidder shall stop the work and make and submit report to Employer and Engineer for their instruction Road excavation is constructed from top layer to bottom layer over the entire cross section Excavation shall be performed carefully to avoid over break or unnecessary disturbance of adjacent surfaces Any over break or disturbance caused by excavation operations shall be backfilled, compacted and restored by the Bidder and as directed by the Engineer Slopes in excavations shall be formed and maintained to prevent the formation of standing water, The Bidder will inspect geometrical factor, flatness of the slope according to technical standards Every 20m length to check quality complete excavation slope in a cross-sectional All excavations shall be finished to reasonably smooth and uniform surfaces In the case the excavated material is suitable for slop protection or for planting trees or grass, or for backfill to structure, embankment which shall made free of sand, stone, rubbish and other foreign matters and complies with the specification will be transported to shoulder of embankment for re-used , if approved by Engineer The excavated shall be stockpiled on the both sides of the road, a part of which will be used to make temporary water-retaining dyke; the remaining will be transported to the disposal area as regulated Excess material shall be placed in the right places The Bidder spray and compaction to make 2% slope on surface of excess material stockpiled, excess material stockpiled no higher than 3m Temporary Ditch shall be set along Excavated Area for gathering surface water Make soakage pit at suitable location Temporary drainage ditches shall be cleaned and trimmed from time to time so that there may be a free flow of water throughout the whole Construction Period After excavation area to laboratory standards, criteria determine whether to design level, the Bidder take soil samples within the work about natural moisture, liquid limit, plasticity index, density and the load capacity swelling from CBR laboratory to to change the material within the area Quality control of excavation construction Check The inspection of excavation construction includes 4/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION Check the material classification and criteria of natural moisture, liquid limit, plasticity index, density standards criteria and the load capacity swelling from CBR laboratory The classification of excavated material into soil or rock shall be made according to the following test using a bulldozer with a hydraulic ripper The test shall be performed by the Bidder under the direction of the Engineer Standard Test Method for Classification of Soil and Rock Test Items Requirements Standard Specification of Test Machine Bulldozer (110CV) with one tyne hydraulic ripper Test Frequency At least one test at a mountain/location on the construction site Test Area Area: 15m X 30m Hauling distance: 20 - 30m Slope of test area : - % Test Method Crushing by ripper and hauling by blade of the bulldozer QR=Net excavation volume (m3) / Time (hr) Criteria for judge of the classification Rock : Qr /Q < 0.4 Q= Standard excavation capacity (21 m3/hr) Check the quality of the construction of geometrical factor, flatness slope Check the disposal Tolerances After excavation the dimensional tolerance for; finished lines, grades and formations of designated areas instructed by the Engineer shall be ±2cm of dimensions shown on the Drawings All exposed finished excavated surfaces shall be; properly graded, uniform and shall have sufficient slope to ensure that they are free draining and free from ponding during rainfall III Rock blasting General description In this part, the Bidder describes method statement for the construction rock excavation by blast fracturing and the constructing of stable final rock cut faces using controlled blasting and production blasting techniques Controlled blasting 5/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION uses explosives to form a shear plane in the rock along a specified back slope Controlled blasting includes presplitting and cushion blasting Production blasting uses explosives to fracture rock in accordance with Specification and in conformity with the lines, grades and typical cross sections shown on the Drawings Method statement 2.1 Preparation 2.1.1 Machine and labor Machine personnel construction are fully prepared by Bidders to ensure quality and quantity Prior to construction, the Bidder trial operation of machinery and equipment to ensure all the equipment stable operation during construction 2.1.2 Preparation construction site Prior to the construction of the embankment, the Bidder conducting the cleanup, grass, tree, stripping of top soil and cleaning obstacles within the construction site, prepare the under layer in accordance with Specification Ensure drainage construction sites 2.1.3 Site Specific Blasting Plan The Bidder will submit site specific blasting plan for acceptance before drilling operations begin included: • Bidder’s drawings showing a scaled map of the blast area and cross sectional views which indicate beginning and ending stations, free face location, hole spacing, hole diameter, hole depth, burden, hole inclination, and sub-drill depth The drawings shall show any significant joints or bedding planes within the blast zone and these geological features shall be incorporated into the blast design • Where blasting may affect nearby structures or utilities, the Bidder shall provide the method of monitoring and controlling blast vibrations • A loading pattern diagram showing the location and amount of each type of explosive to be used in the holes including primer and initiators and the location, type, and depth of stemming, column heights, and overall powder factor for each type of loading • A delay and initiation diagram showing the delay pattern, sequence, and delay times 2.2 Rock excavation by blasting sequence Rock excavation by blasting sequence: • Specify location of drilling and depth of drilling 6/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION • Drill holes with drill D42mm (or D76mm) • Blow, cleaning drilling holes, acceptance drilling holes • Install explosive • Blasting, test explosion sites • Excavation rock to dump truck 2.3 Method statement detail 2.3.1 General Drill and blast shall be made in accordance with the approved blasting plan Before drilling remove overburden soil and loose rock along the top of the excavation for at least 10 meters beyond the hole drilling limits or to the end of the cut; • Cap all holes to prevent unwanted backfill; place a stake next to each hole with hole number and total depth drilled; • Use the types of explosives and blasting accessories necessary to obtain the required results (a bottom charge may be larger than the line charges if no over break results); • Free blast holes of obstructions for their entire depth; place charges without caving the blast hole walls; stem the upper portion of all blast holes with dry sand or other granular material passing the 9.5-millimeter sieve; not stem the hole with drill cuttings; • Following a blast, stop work in the entire blast area and check for misfires before allowing workers to return to excavate the rock; • Remove or stabilize all cut face rock that is loose, hanging, or potentially dangerous; scale by hand or machine methods as approved by the Engineer; leave minor irregularities or surface variations in place if they not create a hazard; drill the next lift only after the cleanup work and stabilization work are completed; 2.3.2 Drill holes Drill holes with drill D42mm (or D76mm) The Bidder shall submit drill logs including the following: • Blast plan map showing designated hole numbers; and • Individual hole logs completed and signed by the driller showing; total depth drilled, depths and descriptions of significant conditions encountered during drilling that may affect loading such as water or voids and date drilled 7/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION 2.3.3 Controlled blasting When test blasts indicate the need for controlled blasting, the Bidder shall use controlled blasting methods to form the final rock cut faces when the rock height is more than meters above the ditch grade and the staked slope is 2:1 or steeper Controlled blasting includes only those holes drilled on the row furthest from the free face and that are drilled on the design slope Down hole angle or fan drill blast holes shall be used for pioneering the tops of rock cuts or preparing a working platform for controlled blasting The blast hole diameter and hole spacing established shall be used for controlled blasting during the test blasts Controlled blast holes shall be drilled not greater than 100 millimeters in diameter along the final rock face line Controlled blast holes shall be drilled within 75 millimeters of the proposed surface location and shall be at least 10 meters beyond the production holes to be detonated or to the end of the cut Drilling equipment with mechanical or electromechanical devices that accurately control the angle the drill enters the rock shall be used A lift height shall be selected and drilling operations shall be conducted in such a way that the blast hole spacing and down hole alignment does not vary more than 225 millimeters from the proposed spacing and alignment When more than percent of the holes exceed the variance the lift height shall be reduced and the drilling operations shall be modified until the blast holes are within the allowable variance Maximum lift height is 15 meters A 600 millimeter offset is allowed for a working bench at the bottom of each lift for drilling the next lower controlled blasting hole pattern The drill inclination angle or the initial drill collar location shall be so adjusted that the required ditch cross section is obtained when the bench is used Drilling 500 millimetres below the ditch bottom is allowed for removing the toe Bulk ammonium nitrate and fuel oil shall not be used for controlled blasting In presplitting, the nearest production blast row shall be delayed by at least 25 milliseconds after the presplit line blasting Presplitting shall be done at a minimum of 10 meters ahead of the production blasting zone In cushion (trim) blasting, the cushion blast row shall be delayed by 25 to 75 milliseconds after blasting the nearest production row IV Embankment General description In this part, the Bidder describes method statement for the construction of subgrade and roadway embankment this work included placing and compacting 8/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION to requirement compaction all materials in accordance with Specification and in conformity with the lines, grades and typical cross sections shown on the Drawings 9/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION Requirement for Compaction Layer Compaction Top 30cm Layer (Subgrade) 98% (22TCN333-06, Method 2D) or AASHTO T180 50 cm Layer below Top 30cm Layer (Subgrade) 95% (22TCN333-06, Method 2D) or ASSHTO T180 Layers below Subgrade 95% (22TCN333-06, Method 2D) or ASSHTO T180 Method statement 2.1 Preparation 2.1.1 Material Construction material will be prepared by Bidder in conformance with the quantity, quality shown on the project specification 2.1.2 Machine and labor Machine personnel construction are fully prepared by Bidders to ensure quality and quantity Prior to construction Bidders trial operation of machinery and equipment to ensure all the equipment stable operation during construction 2.1.3 Preparation construction site Prior to the construction of the embankment, the Bidder conducting the cleanup, grass, tree, stripping of top soil and cleaning obstacles within the construction site, prepare the under layer in accordance with Specification As with the natural substrate, the hollows, to clear the bottom and use the material in accordance with the technical standards for filling Ensure drainage construction sites 2.1.4 Trial section construction The Bidder will carry out in accordance with our method statement for the compaction of each type of fill material to be used in the Works to determine the relation between; the types of compaction equipment, the number of passes required and such methods as may be necessary for adjusting moisture content in order to construct Embankments in accordance with this Specification Section Trials areas will be 10 m wide and 50 m long and subject to the approval of the Engineer 2.2 Construction sequence Embankment construction sequence: 10/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION The expansion joints and its accessories shall be installed in right positions and upon Engineer’s approval Construction of expansion joints 2.3.6 Placing and vibrator concrete mixture Prior paving concrete mixture, the aggregate base course shall be corrected and trimmed in compliance with the gradient, geometrical dimensions, cross section, level etc and surface of which shall be cleaned from dirty and deleterious material and approved by the Engineer The concrete mixer shall be hauled to the site by truck mixer and loaded into the paver Bidder propose to use Pavers HTH60000 and GOMACO, which have been used for paving concrete mixture of other similar works The above pavers can pave concrete mixture regularly without segregation in design thickness overall area to be paved with concrete Concrete mixture shall be placed regularly both side of the joints to be placed with dowel bars and avoid movement of dowel bars during paving concrete mixture The paved concrete mixture shall be compacted almost after placing for avoiding segregation and settlement Due to the concrete mixture is paved bay paver, therefore the Vibrator having vib operation frequency between 7000 and 1200 vibrations/minute with amplitude rang 0.6-1.5mm shall be used for 50/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION compaction overall surface and thickness of paved area This vib compacting is equipped with the vib screed having vib frequency not less than 3500 times/minute for ensuring that the paved concrete mixture is compacted regularly and smoothly The places, where the pacing concrete can be undertaken by paver, so concrete shall be placed by common labor and the compacting shall be undertaken following sequence: • Compacting by Vib Pocker (its vibration frequency >3500 vibrations/minute) overall placed concrete area The Vib Procker shall be operated in straight direction to certain depth of concrete layer for avoiding crack or damage of separate membrane The time for compacting at each point is not more than 45 seconds After that pocker is extracted slowly for avoiding making the holes on the concrete surface and continue to compact next point far from that point about 1.5 diameter of compacting effective of pocker • Compacting by plate compactor (vibration frequency >3500 vibrations/minute) from edges toward the center of paved concrete trip with the internal vibration frequency not less than 500 vibrations/minute • Finish compaction by handle compactor (screed) shall be undertaken overall surface of paved concrete trip os that the level of paved concrete trip is equal to the top of formwork The compacting concrete mixture shall be finished when the overall surface of concrete trip is smoothly and regularly, the coarse aggregate is sink under the surface If the compacting paved concrete is undertaken over requirement, so concrete shall be segregated and influences to quality of concrete The surface finishing shall be undertaken almost after finishing compaction In the case the concrete mixture is placed by common labor, the surface finishing of that concrete area shall be as follows: • Using rolling pipe D100, weight 40kg for initial screeding surface and then using rolling pipe d100, weight 20kg for finish screeding • The screeding is undertaken almost after compacting, the surpus concrete mixture may be added for compaction or removed The screeding the unevenness places shall be undertaken several times until it is smoothly and regularly In any case the paving concrete mixture will not be undertaken in the heavy rain, if heavy rain arisen during paving concrete, so the paving shall be completed as quick as possible the nearest joint and stop and give the notice to the batching plan for stop mixing concrete The concrete moisture area which just paved shall be covered from rainfall in right manner, so that the rain water not wash the concrete and make honey combs Etc 51/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION Placing and vibrator concrete mixture 2.3.7 Making roughness of surface The making roughness of concrete surface shall be undertaken after completion of paving and compacting concrete The interment used for making roughness shall be in 450mm wide and operated in transverse direction of concrete trip and creating regular patches in 1.2mm – 1.5mm depth 52/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION Making roughness of surface 2.3.8 Construction of joints Longitudinal joints: The longitudinal joints shall be done by formwork posited along the paving trip and inserting mastic of joint top and dry concrete Both longitudinal joints in adjacent with road shoulders shall be posited with tie dowel bar for avoiding removed of concrete trip to the shoulder These tie dowel bars shall be posited as design and through the formwork The transverse joints: Construction joint: This will be made at point of finishing working shipment or at the place where the interrupt of work longer than time for concrete settlement The joint shall be made by placing transverse formwork with tie bar If possible, the working joint shall be posited nearly by the expansion joint Expansion transverse joint: This joint shall be made by cutting the ditch for reducing area of concrete surface These ditch may be created by placing the bar in 3-5mm thick and height of 1/5 concrete thick into west concrete mixture and vibration force or cutting by roll saw concrete is being hard 53/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION The sawing ditch on the concrete being hard shall be undertaken so that it will not appearance of cracks due to shrinkage of concrete The time for sawing concrete usually 8-12 hours after concrete completion in order that the concrete is reach to enough strength and hardness for sawing so that the edges of joint will be not cracked or damaged The sawing concrete shall be performed by the skill experience worker 2.3.9 The precautions for early cracks The cracks appear on the paved concrete surface after several days upon completion of paving concrete is called to as the early cracks The cracks are due to change of temperature and moisture, therefore concrete is shrinkage In order to avoid these cracks, the following options may be applied for: • Try to minimize cement volume in 1m3 of mixture and use the cement of low shrinkage, reduce water volume for 1m3 of concrete mixture by using plastic additive and aggregate of good quality • Reducing friction coefficient of surface of base aggregate course (by overlaying oil paper or spraying bitumen Sprinkling water to enough moisture of base aggregate course prior paving concrete • The outside temperature during paving concrete is less than 300C • Limit the time for sawing joint and adjust the time for sawing concrete complied with the working and weather condition Usually sawing 5-6 joint in hard concrete, so sawing on1 joint in wet concrete • Upon paving and completion of concrete, the concrete surface shall be covered in right manner for avoiding sun light and quick vaporization 2.3.10 Curing concrete The curing concrete shall be undertaken upon completion of rough making of overall surface of concrete as follows: • Curing by creating impervious membrane: The entire surface of paved concrete shall be sprayed uniformly with white pigmented curing compound immediately after finishing of the surface and before the concrete has set • Curing compound shall be applied by mechanical sprayers under pressure at the rate of liters to not more than 14m2, then the sacks shall be covered in right manner for three (03) days The curing compound shall not be applied during rainfall The traffic will be closed during curing 54/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION Curing concrete 2.3.11 Remove formwork The formwork shall be remove, when the concrete is reached to more than 25% design strength The time for discharging formwork following the below Table Allowable Time for Discharging Formwork Average (day and night) temperature (00C) Allowable time for discharging formwork 15 20 25 >30 36 30 24 18 The formwork discharging shall be undertaken carefully so that it wills not damage and Brock angles, edges of concrete plates and protect formwork for reuse 2.3.12 Sealing joints Upon completion of concrete curing, the joints shall be cleaned by: • Jetting water of high pressure for cleaning all dirt and deleterious materials; • Blowing by air compressor for drying before sealing mastic Hot Poured Sealant shall be applied uniformly for the full depth of the joint without entrapped air or formation of voids 55/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION The heating kettle shall be of an indirect heating type, constructed as a double boiler A positive temperature control and mechanical agitation shall be provided The sealant shall be heated to the temperatures given in the manufacturer’s information Overheating of the sealant shall not be permitted A direct connecting pressure-type extruding device with nozzles shaped for insertion into the joint shall be provided Any sealant spilled on the surface of the pavement shall be removed immediately Quality control The testing are carried out frequently before, during and after construction Portland concrete pavement This work including but not limited to the following: 3.1 Acceptance Sampling and Testing The Contractor’s testing Laboratory shall perform all acceptance sampling and testing necessary to determine conformity with the requirements of Specification Acceptance sampling and testing shall be conducted for each lot A lot size shall be proposed by the Contractor and approved by the Engineer before the commencement of the Work However the lot size shall not exceed 1500 m2 of pavement or one day’s placement (whichever is less) 3.2 Flexural Strength Samples shall be taken at the batching plant a minimum of two times a day The concrete shall be sampled in accordance with ASTM C172 Specimens shall be made in accordance with ASTM-C31 and the flexural strength shall be determined in accordance with ASTM-C78 3.3 Pavement Thickness Each lot shall be divided into four equal sub-lots and the Contractor shall take one core from each sub-lot Sampling locations shall be in accordance with random sampling procedures contained in ASTM D3665 The Contractor shall fill core holes with a non-shrink grout approved by the Engineer within one day after sampling The Contractor shall furnish all tools, labor, and materials for cutting samples and filling the cored hole The thickness of the cores shall be determined by the average caliper measurement in accordance with ASTM C174 3.4 Pavement Roughness At least 21 days before use, the roughness of the pavement surface shall be measured For this purpose the Contractor shall provide a Multi-purpose Profiling System (including all the necessary devices, hardware and software) for 56/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION calculation of the International Roughness Index (IRI) (AASHTO PP37 or ASTM E950) 3.5 Acceptance Criteria for Concrete Pavement Acceptance will be based on the following characteristics of the completed pavement: Tolerances of Items to be applied to decide Payment Factors Parameters Surface levels Width Thickness by Site Core Sample Tolerance ± mm ± 10 mm ± 8mm Flexural Strength （Class P（ Min 98% Surface Irregularity by 3m straight edge IRI values ( m /km) ± mm ± 2.50 IX Bituminous Surface Treatment General description In this part, the Bidder describes method statement for furnishing Bituminous Surface Treatment apply at frontage road and cross road, this work consists of layers of bituminous seal coat with cover aggregate laid on a prepared base, which is sealed with a bituminous prime coat in accordance with Specification Coat and in conformity with the lines, grades and typical cross sections shown on the Drawings Method statement 2.1 Preparation 2.1.1 Material Construction material main as prime coat, bitumen will be prepared by Bidder in conformance with the quantity, quality shown on the project specification, please reference item … Aggregate Properties of aggregate shall following table Properties of aggregate Properties Compressive strength (daN/cm2) 57/ 64 Required Limits Testing Method TCVN 7572- 06 (Manufacture's PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION certificate shall be made) a Crushed aggregate from magmatic and > 1000 metamorphic rock (daN/cm2) b Crushed aggregate from sedimentary rock > 800 (daN/cm2) Los Angeles Abrasion Test (LA), % a For magmatic and metamorphic rock < 25% b For sedimentary rock < 35% AASHTO T96-87 Crushed aggregated content (at least > 85% fracture faces) of total particles retained on 4.75mm sieve, % By visual observation and percent passing sieve method Aggregate crushing rate > (ratio) By visual observation and percent passing sieve method acceptable TCVN7504:2005 Rc = Dmax/dmin Binding between asphalt cement and aggregate Side of aggregate for bitumen surface treatment Minimum Nominal Sieve Size (d/D)mm Aggregate Size Maximum Nominal Aggregate Size dmin Dmax 16.0 to 19 16 20 9.50 to 16 10 16 4.75 to 9.5 10 Note Rounded values have been used dmin: nominal minimum size of crushed aggregate Dmax: nominal maximum size of crushed aggregate; Particles which are bigger than (D) and (D+5mm) shall not exceed 10% and 3% by weight respectively; Particles which are smaller than (d) and 0.63 d shall not exceed 10% and 3% by weight respectively; Particles which are flat shall not exceed 5% by weight (Vietnamese Standard TCVN 7572-06); 58/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION Particles which are poor and sedimentary shall exceed 3% by weight (Vietnamese Standard TCVN 7572-06); Aggregate shall be dry and clean The material shall have clay dust content not exceeding 1% by weight, of that content of clay ball shall not over 0.25% (Vietnamese Standard TCVN7572-06) Binding between aggregate and bituminous shall meet at least acceptable level (Vietnamese Standard TCVN7504:2005) The aggregate and bitumen content used for DBST shall be as following table: Required aggregate and bituminous content Bituminous Typ e of BST Two layer Thick ness (cm) 2.02.5 Spayin g Sequence Volume (Kg/m2) The first time The second time 1.8 1,2 Aggregate Placing Sequence Aggregate Size The first time The second time (mm) Volu me (Lit/m2) 9.5/12.5 14 – 16 4.75/9.5 10 12 2.1.2 Machine and labor Machine personnel construction are fully prepared by Bidders to ensure quality and quantity Prior to construction Bidders trial operation of machinery and equipment to ensure all the equipment stable operation during construction 2.1.3 Conditioning of Surfaces Before placing the Prime coat, the surface of base course shall be cleaned of all loose foreign materials The existing surface of base course shall be swept until the embedded large aggregate is exposed The surface shall be cleaned by air compressor and manuals Before placing the bitumen and aggregate for BST, the primed surface shall be cleaned until the surface is free of mud or other covering 2.2 Construction sequence Construction sequence for DBST, 3kg/m2 • Conditioning of surface • Stretch cord and install mark poles 59/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION • Placement prime coat • Placement bitumen first layer • Placement aggregate first layer • Rolling first layer • Placement bitumen first layer • Placement aggregate first layer • Rolling first layer • Maintenance 2.3 Method statement detail 2.3.1 Conditioning of surface and Stretch cord and install mark poles Used pneumatic blowers, combined with brooms to clean the surface has been prepared the road surface must be clean dirt, mud, but not bubble the aggregate located in the upper part of the road If the road is dirt then clean by water and waiting for dry before placement prime coat Range of clean pavement wider range of placement bitumen about 0.2 m along the edges When the road surface is clean and dry, applied the prime coat layer on the prepared surface in compliance with the requirements of Technical Specification Prime coat was conducted prior to placement of BST days but not more than days Stretch cord and install mark poles before placement bitumen to bitumen distributor driver can determine the range of placement bitumen 2.3.2 Placement bitumen first layer Use bitumen distributor at a speed of 5km/h to 7km/h to distribution bitumen according to bitumen quantity norms has been approved Ensure bitumen placement on the road surfaces be uniform, full Put strip of building paper, minimum 1m wire and 300 mm longer than the spray bar length at the position where bitumen distributor starts running and stop to avoid uneven bitumen placement At a slope greater than 4% bitumen distributor start from the bottom up to avoid bitumen flowing down When construction BST with more than layer, bitumen shall be placed staggered horizontal, along connection of upon layer and under layer At the location of bitumen distributor cannot access, use hand distributor to supplement placed bitumen When placed bitumen by hand, the worker must ensure that the bitumen placement on the road surfaces be uniform, full The 60/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION worker shall place bitumen in construction lane overlap the other construction lane about 2cm to 5cm 2.3.3 Placement aggregate first layer Use chip spreader combine with truck to placement the aggregate, placement aggregate was carried out immediately after spread bitumen The truck are going back to the wheel always go on spreading new aggregate and wheels not stick to bitumen The speed of the truck and the slits of chip spreader were adjusted to ensure the quantity of aggregate be spread accordance with the technical standard Aggregate will be placement uniform, full on the road surfaces, the aggregate are close together, but not overlapping Additional aggregate at the place where the lack and sweep away aggregate at the place where excess by manually even while aggregate spreader even operating and in the first turn of roller At each construction lane, paving aggregate shall leaving 20cm range bordering along placed bitumen area to distribution bitumen overlap this range when construction next construction lane 2.3.4 Rolling first layer Using tired roller with load per wheel 1.5 T to 2.5 T, ≥ 1.5 m in roller width compacting immediately after each aggregate sprayed In first turns of the roller speed is km / h, in the next turn increase to 10km / h Total turn over the roller is times point Rolling from edge to center of construction lane, overlapping streaks roller be at least 20cm, roller wheels to keep clean and dry Rolling operation shall be done immediately after applying the cover coat material to ensure aggregate embedment without degradation All rolling shall be completed in the same day 2.3.5 Placement bitumen second layer Second layer of placement bitumen done similar to the first layer Note that bitumen have been distribution overlap at between construction lanes 2.3.6 Placement aggregate second layer Second layer of placement aggregate done similar to the first layer 2.3.7 Rolling second layer Second layer of roller done similar to the first layer 2.3.8 Maintenance 61/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION Arrange personnel maintenance within 15 days after finish construction to sweep the discrete stones shot out while driving, repairing local protrusions, lack of aggregate excess bitumen location or vice versa Quality control The testing are carried out frequently before, during and after construction Bituminous Surface Treatment Basic requirements for Bituminous Surface Treatment is good stick to the road surface layer, not flaking out, not were wave cornered, not melted in hot weather 3.1 Check conditioning of surfaces Check the height and dimensions of the surface geometrical Check the flatness of the surface by m long ruler or measuring device IRI Check the cleanliness, dryness of the surface Check the distribution of prime coat according to technical standards: uniform, depth of penetration, freeze waiting time Check the quantity of prime coat used in 1m2 3.2 Check machine and equipment Checking of the normal operation of the equipment department: Distribution equipment, chip spreader combine with truck, rollers For equipment department of distribution equipment: • Status of the insulated bitumen tank: temperature of hot bitumen in the tank is not reduced to the 2.5 oC per hour • The accuracy of the distribution equipment speed meter ± 1.5%; pumps speed meter ±1,5%; bitumen quantity meter ±2%; thermometers measure the temperature of bitumen ±5OC • Height of distribution flame suitable for distribution diagram, respectively with equipment speed, pumps speed and bitumen quantity for 1m • Uniformity of distributed bitumen • The difference between the distributed bitumen over 1m with norms not exceeding 5% For chip spreader and dump truck: • Check the smoothness and flat of tank truck • Check the operation of the outlet and stone discharge slot • Check Bars of stone paving equipment 62/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION • The difference between the stone paving 1m2 with norms not exceeding 8% For roller: • Check tire condition, air pressure, wheel load 3.3 Material testing Before using any material, the Bidder take samples testing according to requirement in item 2.1.1 Stone • Test dryness of small stones, especially after the rain Bitumen • Every day during construction, get bitumen directly from the distribution parts of bitumen distribution equipment to check quality • Check the temperature of bitumen before pump to tank and before spraying Permissible variation of ± 10 ° C • Bitumen had been heater to construction temperature not be kept longer than 8h 3.4 Testing during construction • Testing bitumen distribution to ensure bitumen spread uniformity, norms, temperature • Testing the small stones paving to ensure timeliness, security norms, full-face bitumen • Checking the additional stone work at the place where the lack and sweep away stone work at the place where excess • Checking the bitumen distribution and stones paving at conterminous location • Checking rolling work: rolling diagram, number of turn on a point, rolling speed, status of stone under rolling wheel • Checking maintenance work • Checking traffic organization • Checking safety plan • Checking environmental plan 3.5 Acceptance 63/ 64 PHUONG THANH TRANCONSIN – GRBCC JV CIVIL WORKS CONTRACT PACKAGE A1 (KM 65+000-KM81+150)- DA NANG – QUANG NGAI SECTION Acceptance of construction Bituminous Surface Treatment will be following Technical specification and Vietnamese Standards TCVN8863-2011: Bituminous Surface Treatment - Specification for Construction 64/ 64 PHUONG THANH TRANCONSIN – GRBCC JV ... grade 10 Wax paraffin content % Max 2. 2 22 TCN27901 22 TCN27901 22 TCN27901 22 TCN27901 22 TCN27901 ASTM D6/D5 ASTM D20 42 AASHTO T44 ASTM D70 AASHTO T 228 ASTM D3 625 DIN- 520 15 Polymer Modified Binder (PMB)... 23 0 Loss on heating for hours at 163 °C % Max 0.8 32/ 64 01 22 TCN27901 22 TCN27901 22 TCN27901 22 TCN27901 ASTM D113 AASHTO T151 AASHTO T5396 ASTM D 92 AASHTO T48 ASTM D6 AASHTO T47 PHUONG THANH TRANCONSIN... Original Min 65 22 TCN279-01 ASTM D6/D5 Solubility of % Trichloroethylene C2 Cl4 Min 99 22 TCN279-01 Specific Gravity at 25 °C g/cm3 1.00 - 1.05 33/ 64 ASTM D20 42 AASHTO T44 22 TCN279-01 ASTM D70