CONTENTS 1. INTRODUCTION 4 1.1. GENERAL 4 1.2. RELATED STANDARDS 4 1.3. MATERIALS FOR PILING. 4 1.4. SCOPE OF WORK 5 1.5. GEOLOGICAL CONDITION AND HYDRAULIC CONDITION. 5 1.6. COORDINATE OF BORED PILE: 6 1.7. DETAILED REBAR OF BORED PILE: 6 1.8. ACCESS ROAD 7 1.9. RIVER ROAD 7 1.10. UNSUITABLE MATERIALS 7 1.11. WORKING DRAWING 7 1.12. LIST OF BORED PILE: 7 2. QUANTITY 8 3. SITE ORGANIZATION 9 4. CONSTRUCTION SCHEDULE 11 5. EQUIPMENT AND MATERIAL 12 5.1. Equipment. 12 5.2. Material 13 5.3. Batching Plant. 13 5.3.1. Concrete of contractors. 13 5.3.2. Concrete of Pha Din 18 6. CONSTRUCTION FLOW CHART 19 7. CONSTRUCTION METHOD 21 7.1. Method and sequence of construction 21 7.1.1. Setting out pile location 21 7.1.2. Temporary casing setting 21 7.1.3. Bentonite liquid 22 7.1.4. Boring works 24 7.1.5. Cleaning bored hole for the first time 24 7.1.6. Rebar cage installation 24 7.1.7. Tremie pipe installation 25 7.1.8. Secondary cleaning 25 7.1.9. Concrete placing 26 7.1.10. Removal of temporary casing 27 7.2. Detail of boring method 27 7.2.1. Procedure 27 7.2.2. Boring method 27 7.2.3. The reason cause falling in of drilling hole wall and solution methods: 28 7.3.1. General requirements: 29 7.3.2. Detail of method to mix Bentonite suspension. 29 7.3.3. Supplying and recycling of Bentonite suspension. 30 7.3.4. Recycling of Bentonite suspension: 30 7.3.5. Prevent Bentonite affect to the Environment 30 7.4. Method to clean bored hole 30 7.4.1. Method 1: Cleaning of Bored hole by Pumping. 30 7.4.2. Method 2: Cleaning of Bored hole by Air Compressor. 30 7.5. Installing rebar cage work 31 7.6. Method of concrete placement 32 7.6.1. General requirements 32 7.6.2. Composition and admixture of concrete 32 7.6.3. Transport of concrete 32 7.6.4. Method of concrete placement 33 7.7. Positional Tolerance 34 8. GROUTING SONIC PIPE MEASURE 34 9. GROUTING SONIC PIPE MEASURE 35 10. QUANLITY CONTROL 36 11. SAFETY CONTROL 37 11.1. Everyone working on site 37 12. ENVIRONMENT CONTROL 39 APPENDIX 1: Coordinates and geological layers of bored pile APPENDIX 2: Risk analysis in bored piling APPENDIX 3: Inspection of pile construction machines APPENDIX 4:Dumping method APPENDIX 5: Construction drawings of bored pile 1. INTRODUCTION 1.1. GENERAL The objectiveof thismethod statement is todescribetheconstruction methodology and procedure forpiling workofbelowbridgesofpackgeA3:Tra Bong.Thesizesof thepilestobe coveredby thismethod statementarediameter1200mm.Planandprofileofboredpileofthese bridgesareattachedinShopDrawing. 1.2. RELATED STANDARDS TCVN9395:2012 Bored PilesConstruction, Check and Acceptance. TCVN 9396:2012 Bored PilesDetermination of Homogeneity of Concrete – Sonic Pulse Method. TCVN 9393:2012 PileStandard Test Method for Insitu Piles Under Axial Compressive Load ASTM D4945 Pile Testing Using Large Deformation Method 1.3. MATERIALS FOR PILING. 1.3.1. Concrete a) Bored Piles shall be constructed in accordance with the details shown on the Drawings and in accordance with Specification Section 07100 Concrete and Concrete Structures. b) Concrete shall conform with the applicable provisions of Specification Section 07100 Concrete and Concrete Structures 1.3.2. Reinforcing Steel Reinforcement shall conform with the requirements of Specification Section 07500 Reinforcing Steel 1.3.3. Temporary Casings a) Temporary casings shall be used to maintain the stability of pile excavation, which might otherwise collapse. b) Temporary casings shall be free from significant distortion. They shall have a uniform cross section throughout each continuous length. During concreting they shall be free from internal projections and encrusted concrete which might prevent the proper formation of piles. 1.3.4. Bentonite and Bentonite Slurry (Drilling Fluid) a) Supply i) Bentonite shall be in accordance with Vietnamese Standard TCVN 9395:2012. b) Mixing i) Bentonite shall be mixed thoroughly with clean fresh water to make a suspension which will maintain the stability of the pile excavation for the period necessary to place concrete and complete construction. ii) Where chemically contaminated groundwater occurs, special precautions shall be taken to modify the bentonite in all respects for the construction of piles. 1.4. SCOPE OF WORK This method statementincludesthefollowingscope of works: (1)CastinplaceConcretePilingD=1,200mm (2)HumusTesting(refertosection7300 ofspecification) (3)CompressionTesting (refer tosection 7100ofspecification) (4)SonicTesting (referto section 7300 ofspecification) (5)Pile DynamicTesting(refer tosection 7300ofspecification) 1.5. GEOLOGICAL CONDITION AND HYDRAULIC CONDITION. 1.5.1. Geological condition Tra Bong Bridge. 1.5.2. Hydraulic condition
METHOD STATEMENT Document No.: Version: 01 DANANG – QUANG NGAI EXPRESSWAY PROJECT PACKAGE A3: KM99+500 ÷ KM110+100 BOREDPILESWORKS Submissiondate: 28/11/2014 Page of 42 CONTENTS APPENDIX 1: Coordinates and geological layers of bored pile APPENDIX 2: Risk analysis in bored piling APPENDIX 3: Inspection of pile construction machines APPENDIX 4:Dumping method APPENDIX 5: Construction drawings of bored pile METHOD STATEMENT Document No.: Version: 01 DANANG – QUANG NGAI EXPRESSWAY PROJECT PACKAGE A3: KM99+500 ÷ KM110+100 Submissiondate: 10/12/2014 BOREDPILESWORKS Page of 42 INTRODUCTION 1.1 GENERAL The objectiveof thismethod statement is todescribetheconstruction methodology and procedure forpiling workofbelowbridgesofpackgeA3:Tra thepilestobe Bong.Thesizesof coveredby thismethod statementarediameter1200mm.Planandprofileofboredpileofthese bridgesareattachedinShop-Drawing 1.2 RELATED STANDARDS TCVN9395:2012 Bored Piles-Construction, Check and TCVN 9396:2012 Acceptance Bored Piles-Determination of Homogeneity of Concrete – Sonic Pulse Method TCVN 9393:2012 Pile-Standard Test Method for Insitu Piles Under Axial Compressive Load ASTM D4945 Pile Testing Using Large Deformation Method 1.3 MATERIALS FOR PILING 1.3.1 Concrete a) Bored Piles shall be constructed in accordance with the details shown on the Drawings and in accordance with Specification Section 07100 - Concrete and Concrete Structures b) Concrete shall conform with the applicable provisions of Specification Section 07100 - Concrete and Concrete Structures 1.3.2 Reinforcing Steel Reinforcement shall conform with the requirements of Specification Section 07500 - Reinforcing Steel 1.3.3 Temporary Casings a) Temporary casings shall be used to maintain the stability of pile excavation, which might otherwise collapse b) Temporary casings shall be free from significant distortion They shall have a uniform cross section throughout each continuous length During concreting they METHOD STATEMENT Document No.: Version: 01 DANANG – QUANG NGAI EXPRESSWAY PROJECT PACKAGE A3: KM99+500 ÷ KM110+100 BOREDPILESWORKS Submissiondate: 10/12/2014 Page of 42 shall be free from internal projections and encrusted concrete which might prevent the proper formation of piles 1.3.4 Bentonite and Bentonite Slurry (Drilling Fluid) a) Supply i) Bentonite shall be in accordance with Vietnamese Standard TCVN 9395:2012 b) Mixing i) Bentonite shall be mixed thoroughly with clean fresh water to make a suspension which will maintain the stability of the pile excavation for the period necessary to place concrete and complete construction ii) Where chemically contaminated groundwater occurs, special precautions shall be taken to modify the bentonite in all respects for the construction of piles 1.4 SCOPE OF WORK This method statementincludesthefollowingscope of works: (1)Cast-in-placeConcretePilingD=1,200mm (2)HumusTesting(refertosection7300 ofspecification) (3)CompressionTesting (refer tosection 7100ofspecification) (4)SonicTesting (referto section 7300 ofspecification) (5)Pile DynamicTesting(refer tosection 7300ofspecification) 1.5 GEOLOGICAL CONDITION AND HYDRAULIC CONDITION 1.5.1 Geological condition Tra Bong Bridge METHOD STATEMENT Document No.: Version: 01 DANANG – QUANG NGAI EXPRESSWAY PROJECT PACKAGE A3: KM99+500 ÷ KM110+100 BOREDPILESWORKS Submissiondate: 10/12/2014 Page of 42 Filling soil, cultivated soil Poorly graded sand, loose (SP) Low plastic ity silt, soft (ML) Poorly graded sand with gravels, medium dense (SP) Low plasticity silt, high plasticity clay, with grits, very stiff to hadr (ML, C H) Silty sand, Poorly graded sand, medium dense (SM, SP) Poorly graded, well graded gravel with silt, clay, medium den to very dense (GP, G C , GW-GM) Granodiorit Moderately weathered interbeded with, slightly weathered hard roc k (V-2, V-1) G ranodiorit highly to extremely weathered hard rock (V-3), bec omes sands, grits and rock fragments G ranodiorit moderately weathered hard roc k (V-2) G reen sc hist highly to extremely weathered hard rock (V-3) High plastic ity c lay, soft (C H) Green sc hist moderately weathered hard rock (V-2) Green sc hist slightly weathered hard rock (V-1) Green sc hist Fresh to Slightly weathered hard rock (V-1) 1.5.2 Hydraulic condition 1.6 CO-ORDINATE OF BORED PILE: Co-ordinate of bored pile shown on Appendix 01 1.7 DETAILED REBAR OF BORED PILE: Detailed Rebar of Bored Pile is shown in Shop Drawing METHOD STATEMENT Document No.: Version: 01 DANANG – QUANG NGAI EXPRESSWAY PROJECT PACKAGE A3: KM99+500 ÷ KM110+100 BOREDPILESWORKS Submissiondate: 10/12/2014 Page of 42 1.8 ACCESS ROAD Access road construction is designed to right expressway, the road width is meters The drawing road service are separate Before starting work, we will submit the agreement of the access path on local and access road of construction 1.9 RIVER ROAD Construction of piers outside the river was conducted in the dry season Before starting work, conducting licensing procedures and ensures stop the flow Of application for permits procedures waterways are separate 1.10 UNSUITABLE MATERIALS Dump waste materials in Binh Long Elementary School (cluster A) Drawings waste dump are separate 1.11 WORKING DRAWING Prior tocommencementofwork,WorkingDrawingwillbe submitted separatelyshowing designated areas forthe works 1.12 LIST OF BORED PILE: Tra Bong Bridge Elev of Elev of tip bottom of of pile pilecap ELE2 ELEL1 (m) (m) -0.246 -24.246 -0.607 -12.107 Diamete r of pile Length of pile (L) A1 P1 (mm) 1200 1200 (m) 24.0 11.5 P2 1200 16.5 -0.281 -16.781 10 Type P3 1200 16.5 -0.013 -16.513 12 Type P4 P5 P6 1200 1200 1200 25.0 25.0 25.0 -1.901 -1.945 -3.547 -26.901 -26.945 -28.547 12 Type 12 Type 12 Type P7 1200 25.0 -4.755 -29.755 12 Type P8 1200 25.0 -5.493 -30.493 12 Type P9 P10 A2 1200 24.0 -6.773 -30.773 12 Type Abutment , Piers Total Number of pile Type of pipe (nos) 20 Type 10 Type 124 METHOD STATEMENT Document No.: Version: 01 DANANG – QUANG NGAI EXPRESSWAY PROJECT PACKAGE A3: KM99+500 ÷ KM110+100 BOREDPILESWORKS Submissiondate: 10/12/2014 Page of 42 QUANTITY Base on the quantity in BOQ, the quantity as follows: D1-5 D1-5 D1-5 D1-5 D1-5 D1-5 D1-5 Section 0730002 0730005 0730007 0730008 0730009 0730010 0730 Bored Pile Unit Quantity Bored Pile 1200mm diameter m 2,746.00 Static Load Test (Dia.1200mm pile) no 1.00 sectio n 744.00 no 6.00 no 2.00 no 1.00 Sonic Test Compression Test for Core Samples from Pile Tip Humus Test at Pile Tip (in Humus Test pipe Dia 1.10mm) Pile Dynamic Test (PDA) METHOD STATEMENT Document No.: Version: 01 DANANG – QUANG NGAI EXPRESSWAY PROJECT PACKAGE A3: KM99+500 ÷ KM110+100 SITE ORGANIZATION Siteorganization for: BOREDPILESWORKS Submissiondate: 10/12/2014 Page of 42 METHOD STATEMENT Document No.: Version: 01 Submissiondate: 10/12/2014 BOREDPILESWORKS DANANG – QUANG NGAI EXPRESSWAY PROJECT PACKAGE A3: KM99+500 ÷ KM110+100 Page of 42 Siteorganization forCast-in-place Concrete PilingWorkis shownbelow: Chỉ huy trưởng cơng trình Phạm Việt Hùng Tel: 0982902927 Mail: mrhungincico@gmail.com Chỉ huy phó Nguyễn Bách Khoa Tel: 0915.387.799 Mail: nguyenbachkhoa79@gmail.com Phụ trách hành chính: Phụ trách kỹ thuật: Bành Thị Thu Trang Đào Tuấn Anh Chỉ huy phó Phạm Văn Dũng Tel: 0982.177.177 Mail: phamdungxhp12345@gmail.com Phụ trách thi cơng: trách an tồn, mơiPhụ trường: trách kháo sát: Lê Hà Thành Phụ trách chất lượng, kếPhụ hoạch: Nguyễn Duy Dũng Phạm Đức Bình Điện thoại: 098.980.3080 Tăng Tiến Dũng Tel: 043.6417266 Tel: 043.6417266 Email:lehathanh@ymail.com Tel: 0936.238.556 Tel: 043.6417266 Tel: 043.6417266 Email:incicogroup@gmail.com Email:incicogroup@gmail.com Email:incicogroup@gmail.com Email:incicogroup@gmail.com Email:dungincico@gmail.com Kỹ thuật trường: Tạ Văn Cương Tel: 043.6417266 Email:incicogroup@gmail.com Kỹ thuật trường: Trần Đức Tú Tel: 043.6417266 Email:incicogroup@gmail.com Kỹ thuật trường: Phí Ngọc Thụy Tel: 043.6417266 Email:incicogroup@gmail.com Drilling Team Đội khoan Rebar Team Đội gia công thép Concrete Team Đội bê tông No Work Description General Bored pile work Job Classification Detail Manpower Site Manager SiteEngineer Foreman The drilling operator Thecraneoperator Drilling Machine crane Remarks Dayand Night Dayand Night Dayand Night METHOD STATEMENT Document No.: Version: 01 DANANG – QUANG NGAI EXPRESSWAY PROJECT PACKAGE A3: KM99+500 ÷ KM110+100 Theexcavatoroperator Submissiondate: 10/12/2014 BOREDPILESWORKS Page of 42 excavator CommonWorker 40 Dayand Night Dayand Night Electrician Dayand Night CONSTRUCTION SCHEDULE TASK NAME Construction time I Test pile Mobilization 10 day Test pile construction and curing 20 day Quality checking and preparation 10 day Static load test and report 10 day II Mass pile P3 (12 pile) 40 day P2 (10 pile) 30 day P1 (10 pile) 30 day A1 (20 pile) 65 day P6 (12 pile) 50 day P5 (12 pile) 50 day P4 (12 pile) 50 day P7 (12 pile) 50 day P8 (12 pile) 50 day P9 (12 pile) 50 day 15-Jan Fe-15 15-Mar 15-Apr 15-Jul 15-May 15-Jun Depending on soil layers, the Construction team could adjust the mixture by adding additive to meet to requirement 1.2.4 Recycling of Bentonite suspension: During in Cleaning Bored hole or placing concrete, drilling Fluid sucked back to de-sander and recycling to clean it before being supplying tank 1.2.5 Prevent Bentonite affect to the Environment Embankment surrounding of construction site to prevent Betonite flood into the river Arrange a boot (2x2x1)m to recover the flooded Bentonite and then recycling after de-sander Arrange interlining canvas to prevent Bentonite leak into the ground Abundant Bentonite and sandy are moved to the approved dump 7.3 Method to clean bored hole In case of height of sediment at bottom of bored hole is more than 2m, contractor should use Drilling Bucket to take out it before carrying out clean bore hole 1.2.6 Method 1: Cleaning of Bored hole by Pumping The cleaning of bored hole will be carried out by Pumping connecting with Tremie pipe to absorb sediment and bentonite suspension in bottom bore hole and supply new bentonite to replace at the same time Firstly, tremie pipes are connected together by threaded head to bottom pile At depth 6-20m from Casing Top, we directly connect Pumping 90m3/h with Tremie Pipe Each of pumping dead has threads to connect to Tremie pipe Level for installing Pumping is belong to degree sediment at bottom of bore hole to adjust reasonably so that Attractive power is enough strong to attract sediment at bottom of bore hole Then, operating Pumping to absorb sediment and bentonite suspension in bottom bore hole Time for cleaning of bottom of bored hole in the first time is at least hours 1.2.7 Method 2: Cleaning of Bored hole by Air Compressor After finishing drilling to designed level, contractor carry out clean bored hole with the method following: Installing Tremie Pipe D273 into Bored hole; the Level of head of Tremie Pipe is 30 -50cm from bottom of Bored Hole Installing the 60cm Air Tube inside Tremie Pipe to level that is 2/3 length of bored hole from bottom of Bored Hole At the head of air tube, we install an air distributer Installing the cleaning toper at top of Tremie pipe; The cleaning toper have two valves, one is jointed with Air Tube and one is joint channel to recycle Bentonite slurry adulterating soil in bored hole When starting cleaning bored hole, the high compress air is blown continuously with 7-9kg/cm2 tension by the 10 m3/phút air compressor, passing the air tube to the air distributer When the compress air is out of the air distributer under bored hole, it will turn back to go up due to principle of differential pressure inside and outside of Tremie pipe It makes an aspirate pressure at bottom of bored hole to absorb bentonite slurry adulterating sediment following tremie pipe to de-sander flowing bentonite tank During cleaning bored hole by air compressor, bentonite slurry continuously is supplied to compensate inside bored hole in order to ensure level and pressure of Bentonite slurry in bored hole not change Time of cleaning is by – hours After stopping to supply air compress, contractor use measuring tape to check bottom level of bored hole for obtaining design level Cleaning work is considered as finishing when sediment at the bottom is less than 5cm and result of checking properties of bentonite being achieving with specification 7.4 Installing rebar cage work Rebar cage will be fabricated in accordance with the approved Shop Drawings The lowest reinforcing cage will be put into the casing and temporarily fixed at section to be spliced with next reinforcing cage in such a manner as the steel shape H100 is crossing the top of temporary casing The spacer made by the reinforced steel will be fabricated and installed at the main bars of the side of the reinforcing cage by welding in accordance with the approved Shop Drawings The next reinforcing cage will be loaded and connected to the previous cage using of the crane After completion of connection of both cages, the connected cage will be put into the bored hole in the same method as aforesaid and spliced with the next cage The reinforcing cage will be spliced and put into the bored hole up to its bottom, repeating the aforesaid procedures Contractor will check the level of the top of pipe casing before and after Reinforcing steel cage sinking Contractor will carefully check after welding the joints of sonic pipes and core drilling pipe To determine the quality of joining points after welding, contractor will pump up water in sonic pipe and core drilling pipe, and if the water level remains unchanged, welded lines is up to the requirement The steel pipe for sonic D60mm & D114mm shall be put into the bored hole together with reinforcing cage After installing last cage, use rebars D25~D28 with hook and fixed joint to the top of well casing to prevent steel cages from being lifted up and sunk in the process of concrete placement as the figure below: 0 CROSS SECTION - 96 1008 1200 96 7.5 Method of concrete placement 1.2.8 General requirements The concrete shall be placed continuously Slump is measured at the time of discharge in to bore hole shall be in accordance with the approved material The Contractor will test the slump of concrete for each truck mixer Concrete shall be poured when the Bentonite suspension meet the specification shown on Table Tremie pipe shall be cleaned and watertight throughout and enough to be under pressure during pumping smooth on both inside and outside of the tremie Each segment of the tremie pipe is about 2~6m long The joint shall be watertight and easy assembled 1.2.9 Composition and admixture of concrete Concrete mixture shall be in accordance with the technical specification 1.2.10 Transport of concrete Concrete shall be transported from the mixing plant which is located at Tra Bong site bridge or use commercial concrete (Backup batching plant): Concrete station Pha Din in Binh Thach - Binh Son - Quang Ngai to the casting place by 6-8 m3 truck mixer The Contractor will ensure the time from mixing to pouring concrete is not allowed to be over 90 minutes (ASTM C94 12.7) 1.2.11 Method of concrete placement Before placing concrete, the contractor must have the cleaning bored hole method if the slurry sample at 0.5m to the bottom of bored hole has the density > 1.25 g/cm3, sand content > 8%, adhesiveness > 28s Before placing concrete, the tremie pipe reaches to the bottom of bored hole, it shall be lifted up for 20cm in order to keep the enough clearance to discharge concrete The spongy ball shall be put in the tremie, under the funnel neck is about 20~40cm to keep the concrete and Bentonite suspension separately After completion of the above procedures, the tremie pipe will be lightly lifted so that the gap between the end of tremie pipe and the bottom of bored hole is 40cm in the first time of placing concrete The concrete will be directly provided from Mix Truck or Pipe of concrete pumping machine (if necessary) into the funnel of tremie pipe and the concrete slump will be as the approved material during placing It shall be managed that at least 2m and not more than 5m of the tremie pipe is buried in the concrete of the bored hole Contractor will fabricate filter net by Rebar D10, @150mm welding at funnel mouth to prevent big aggregate (if any) fall inside tremie pipe To prevent concrete from being stuck and jammed inside Tremie pipe, contractor will adjust the speed of concrete placing suitably Contractor should prepare rain - cover in case raining while placing concrete Sampling concrete mixture should be conformed to the technical specification of project Sampling position: at batching station and construction site Sample preservation: Contractor will store, preserve sample of concrete in the laboratory at site After completion of placing concrete, all the records related to this work shall be submitted to the Engineer The contractor shall control the temperature of concrete is not exceeding 32 0C ins t al l at io n o f t r emie pil e Pl ac ing Co nc r et e w o r k Shape steel H100 EXISTING ELEVATION Shape steel H100 Bentonite Tremie pipe PILE TIP ELEVATION 7.6 Positional Tolerance The positional tolerances for bored piles shall be as follows: PILE TIP ELEVATION The centre of the completed pile at the cut off level shall not deviate more than 80mm from the theoretically correct position shown on the Drawings The inclination of the pile shall not deviate more than 1:100 from the required vertical alignment After completion of all piling work and prior to casting the pile top into the pile cap or foundation, the top of the reinforcement cage shall be no more than 150 mm above and no more than 75 mm below the correct position and the top of the concrete shall be within 25 mm of the correct elevation The bottom of the shaft excavation shall be normal to the axis of the pile within 60 mm per meter of pile diameter Where a casing is used, its outside diameter shall not be less than the shaft diameter shown on the Drawings The diameter of cast in-situ piles shall be at least 97% of the specified diameter GROUTING SONIC PIPE MEASURE 1.1 Purpose Grouting cement, sand and cement to fill the sonic pipe 1.2 Equipment and manpower High air compressor Special grouting machine Capacity 3m3/h Grouting height 40m Grouting distance 150m Motor power 4KW Pressure 2Mpa Nozzle diameter 64mm Exhaust diameter 38mm 1.3 Measure In order to ensure the quality of grouting in the pipe obtain requirement strength, not segregate, not pock-marked The measure should be carried out the stage follow as: Use air compressor to take water in sonic pipe out Prepair suitable grout follow the technical specification Use grouting machine to fill grout into the pipe from the bottom to the top of the pipe The grouting pipe is withdrawed gradually in the same time with the height of grout in sonic pipe With the pressure of machine, gravity load and the mobility of grout, the sonic pipe will be filled fully without the segregate and pock-marked GROUTING SONIC PIPE MEASURE a Waste Water Treatment Solution of waste water was solved by small tank for overflowed slurry from bored hole and excavated pond for overflowed slurry from excavated soil while excavated soil/mud shall be transported by trucks to approved disposal area Excavated pond is to collect all waste waste/slurry from the excavated soil and to prevent waste slurry from expanding to other areas Working Under Raining During construction, all activities concerning to electrical work shall be stopped if raining All electric boxes shall be protected by roof to prevent water from entering inside If concrete work is being carried out and it rains, activities shall be continued as usual with the plastic covers for the concrete hooper and concrete mixing trucks c Tremie Pipe Getting Stuck Removing & cleaning inside tremie pipe from bored hole if it is stucked Re-installation the tremie pipe up to level higher than the stopping level of concrete 30cm Starting concrete again same with beginning up to 1m height then tremie pipe will be connected and make it down 1.3m After that, concrete work can be continued until the new concrete level which is higher than designated one 2m d Broken Drilling Machine Repairing work for broken machine will be carried out immediately by a mechanics e Diameter and verticality of bored hole not satisfy requirements: First used side cuter of drilling bucket to cut the protruding soil by move bucket to diameter or verticality of bored hole not satisfy requirements area and rotate the bucket to cut the protruding soil of bored hole wall Second used steel casing 6m length, 1.2m diameter and 12mm thickness to repair the wall of bored hole Steel casing will be put in bored hole by drilling rig and move to repair area and then lift up steel casing and free drop down steel casing to whittle the wall of bored hole b 10 QUANLITY CONTROL 1.3 General All materials shall comply with all requirements in the specifications and their samples shall be taken and tested under the supervision of the Engineer before using Only approved materials by the Engineer in the specifications and quality control plan shall be used Should the materials not comply with the requirements of the specifications, they shall be removed from the site The sources approved shall be used throughout the project, and the sample of material in the new source shall be taken and tested for the Engineer’s approval in accordance with the Specifications if the source thereof is changed All the materials required to place the concrete of pile shall be enough stored to mix and supply concrete without interruption during placing of pile concrete 1.4 Reinforcement Reinforcing steel bars shall meet the requirement of the following shop drawings and specification of Section 07500 Reinforcing steel stored at the site shall be laid on wood floors so that no reinforcement steel shall be laid upon or come in contact with the ground If rainy or humid weather occurs or is anticipated, bars shall be stored under cover 1.5 Bentonite Bentonite shall be in accordance with specification of TCVN326-04 or 22TCN257-2000 Bentonite shall be stored in the storage tank at site Bentonite shall be mixed thoroughly with clean fresh water The temperature of the water used in mixing the Bentonite suspension, and of the suspension when supplied to the borehole, shall be not lower than 5˚C The tests for Density, Viscosity, Shear strength and PH of Bentonite shall be made before starting work 1.6 Concrete Concrete Mixing and Delivery: The mix design of concrete shall be in accordance with the submitted by the Contractor and approved by the Engineer The batching plant shall include separate bins for the cement, fine aggregate and for each size of coarse aggregate, a weighing funnel, and scales capable of determining accurately the weight of each component of the batch Accuracy of each component of the batch shall be within allowance as provided in the specification Mixing and delivery of concrete shall be in accordance with the appropriate requirements of ASTM C94 When the concrete is not produced due to unexpected reasons in one concrete batching plant, it will be supplied from another plant located to place the concrete without interruption The slump of concrete for piling shall be as the approved material during placing The test cylinders shall be taken for the concrete of each pile and the relevant tests shall be done by the procedures as provided in the specifications in Site Laboratory 11 SAFETY CONTROL 1.7 Everyone working on site Must be trained Labor Safety – Environmental Sanitation before work, be physically fit, in the age of laborer And make sure that they understand their job done 1.8 Site preparation: - Clean works site tidy before construction Check to make sure that there is no original potential risks such as: bombs, bullet, underground cable… - Isolate, not allow the unauthorized entry to construction area - Signs will be installed at appropriate locations 1.9 Equip labor protection: Everyone working in the site is fully equipped labor protection such as: labor protective shoes, hats, clothing Also, different works will be equipped different labor protection in accordance with the task and as prescribed by law, such as glass, welding gloves when performing welding and cutting, seatbelt when working on 2m high or more 1.10 Lifting safety: Contractor ensures that all lifting machinery serving in site that are in the list of stringent requirements for safety Contractor ensures that the operators of equipment of stringent requirements for safety to be trained on occupational safety in the use of machinery and equipment and got such equipment operator’s license Before performing lifting must inspect operating equipment plan, if equipment safety is not guaranteed, it will be processed and calculated accordingly Check equipment before performing lifting, only safety ensuring machinery and equipment shall be done Cable, mani must be checked before work Lifting area will be isolated with warning wire and warning sign system and have signalman Work only to be done in the presence of site supervisor Load is not allowed to sit on, under No unauthorized entry to the lifting area It is not allowed to cling to the load when performing lifting It is not allowed to lift permissible overload equipment Ensure that signals between the operator and the co-worker are uniform When taking a rest or ending of working shift to shut off and close the equipment 1.11 Concrete work Workers doing concrete work will be furnished labor protection such as: safety clothes, shoes (boots), hat, glasses if working on over 2m high Workers should absolutely not stand under concrete pumping crane if it is pumping crane and stay out of the rotation of car pick if pouring by car pick Motor vehicles for construction must stand away from the pit mouth a safe distance Working platform surface must be bigger or equal to 30cm Pouring crane for concrete car must ensure large enough, surely, ensuring the safety of people involved in the construction Reference to TCVN5308 - 1991 1.12 Reinforced steel work Workers doing concrete work will be furnished labor protection, such as: safety clothes, shoes, hats, gloves if working at height over 2m People who this work must ensure good health The machinery and equipment in service are checked to ensure that it guarantees the safety without electrical leakage, fully safety equipment, earthed and are well shielded Materials and equipment used to make working platform, support pole must ensure good quality: no warping, no termite, no defects, Workers used welding and cutting machines must be trained and experienced Steel cage in the process as well as complete must be safely inserted to ensure that cage will not be moved Arrange 01 electrician to serve electrical connection If working at night will be arranged lighting to ensure the safety of workers and the related Safety officer will monitor regularly at the construction locations When performing work lowering steel cage, no unauthorized entry to the construction area 1.13 Electrical safety Workers working with the electricity will be equipped with proper labor protection, such as: insulated protective clothes, shoes, boots, hats and in accordance with electrical regulations Contractor will send 01 professional electrician to serve works related to electricity on site Wires used in the project is to ensure quality (2 casings or more), are calculated to match the power consumption of each device and use wired with up 02 casings Electrical cabinets ensure safety: no leakage, have general Circuit Breaker, emergency disconnecting button, grounded, Sockets, plugs used in the project must ensure quality and in accordance with safety standards for electricity Electrical equipment used in the project must ensure the safety and regularly maintained by an electrician Welders, cutters, saws, drills, must ensure insulation and adequate safety devices such as protective shield, grounding, All wires used in construction must be high from the ground, water surface accordingly Supply enough light for the construction area Also should apply TCVN5308 - 1991 1.14 Deep pit: Deep pits are screened, warned Drilling holes will be filled after discharging It is not allowed to load supplies, materials near the hole mouth It is not allowed to let truck to pour materials near the pit mouth or turn near the pit edge When the foundation pit reaches the depth of 2m must regularly arranged no less than people at work, but stand apart a necessary distance to timely emergency in the event of occurring unexpectedly accidents Pit mouth should be beveled 450, or reinforced with planks, poles or other appropriate means to ensure no erosion Reinforcing model depending on the type of holes, grooves, nature of foundation and source of groundwater 12 ENVIRONMENT CONTROL Prior and during the execution of work on site, basic safety precautions will be implemented to work efficiently and to prevent any accident or casualties During the process of construction, installation, Contractor’s constructing units working in the site must: The drilling solution have to be recycled in order to ensure it’s not overflow or effect to the environment around the site Not to cause pollution exceeding the permissible level for the environment surrounding the site: • Discharge harmful elements such as dust, toxic gas, noise etc.; Discharge water, mud, wasted materials, soil, sand into the population area, roads, ponds and lakes, planting field surrounding the site that cause bad impact on living and production of the population around Not to cause danger for the population living surrounding the site Not to cause sagging, eboulement, cracks, collapse for the surrounding houses, buildings and technical infrastructure (cable system, underground pipeline, sewer, ditches…) surrounding the site Not to cause hindrance for traffic activities by encroaching roadway, sidewalk Not to let events of fire, explosion happening After construction completion, all construction units must put the site in order, neat and clean; remove all excess materials, demolish temporary facilities, repair damaged parts of surrounding road, sidewalk, sewer and trench, technical infrastructure, houses and buildings etc caused by the construction process strictly in accordance with initial agreement or current regulations issued by the Government The best practices consist of : Inorganic waste should be disposed of in an approved sanitary landfill sites away from the construction areas, or be recycle where this is economically feasible Any remaining organic non-toxic wastes should be ploughed into the soil layers All ground areas where toxic wastes have been spilled should be cleaned using neutralizing materials All areas where oil has been spilled should be ploughed or tilled using agricultural implementations, to facilitate the accelerated chemical breakdown of the oil If any other problems occurred in the site, applicable counter measures or prevention action will be considered immediately and executed as soon as possible At the management level, these matters will be controlled by the respective Construction Manager, and implementation by the respective Site Engineer • APPENDIX Coordinates and geological layers of bored pile APPENDIX Risk analysis in bored piling APPENDIX Inspection of pile construction machines APPENDIX 4: Dumping method APPENDIX Construction drawings of bored pile ... construction 1.1 .1 Setting out pile location The surveying will be carried out using the bench marks approved by total station The center point of pile will be marked as specified in the Drawings 1.1 .2... vibrating hammer Step – lifting out of head pile by crane 7.2 Detail of boring method 1.1 .11 1.1 .12 Procedure After inspection co-ordinate of pile center, we prepare... (Dia.1200mm pile) no 1.0 0 sectio n 744.00 no 6.00 no 2.00 no 1.0 0 Sonic Test Compression Test for Core Samples from Pile Tip Humus Test at Pile Tip (in Humus Test pipe Dia 1.1 0mm) Pile Dynamic