i APPLICATION OF DYNAMIC AND VIBRO COMPACTION METHODS FOR DENSIFICATION OF GRANULAR FILL IN RECLAIMED LAND IN SRI LANKA Amil Indumini Samarasinghe (168980V) Degree of Master of Engineering in Foundation Engineering and Earth Retaining Systems Department of Civil Engineering University of Moratuwa Sri Lanka September 2019 ii APPLICATION OF DYNAMIC AND VIBRO COMPACTION METHODS FOR DENSIFICATION OF GRANULAR FILL IN RECLAIMED LAND IN SRI LANKA Amil Indumini Samarasinghe (168980V) Thesis submitted in partial fulfilment of the requirements for the degree of Master of Engineering in Foundation Engineering and Earth Retaining Systems Supervised by Dr. L.I.N. De Silva Department of Civil Engineering University of Moratuwa Sri Lanka i DECLARATION I hereby declare that, this is my own work and this thesis does not incorporate without acknowledgement of any material previously submitted for a Degree or Diploma in any other university or Institute of higher learning to the best of my knowledge and belief. It does not contain any material previously published or written by another person except where the acknowledgement is made in text. Also, I hereby grant to University of Moratuwa the non-exclusive right to reproduce and distribute my thesis, as whole or a part in print, electronic or other medium. I retain the right to use this content in whole or part in future works (such as articles or books). …………………………… ………………………... A.I. Samarasinghe Date The above candidate has carried out research for the Master’s thesis under my supervision …………………………… ……………………… Dr. L.I.N. De Silva Date ii ACKNOWLEGEMENT At the outset, I would like to express my sincere and heartfelt gratitude to my research supervisor, Dr. L.I.N. De Silva for the continuous support to my study with guidance, motivation and immense knowledge. Without his dedicated supervision and continual guidance, this thesis would not be successfully completed within the time frame. During this period, he basically allowed this research to be my own work while steering me towards the right direction whenever he thought that I needed it. It is my duty to pay gratitude to Eng. Nihal Rupasinghe, the Secretary to the Ministry of Megapolis and Western Province Development, Mr. Nihal Fernando, Project Director, Colombo Port City Development, Eng. Bimal Prabath Gonaduwage, Deputy Project Director, Colombo Portcity Development Project for providing me required data without restrictions. In addition, It is my duty to pay my heart felt gratitude to all teachers served in or visited to Geotechnical Engineering Unit, Department of Civil Engineering including Professor Puswewala, Professor S.A.S. Kulatilake, Professor Saman Thilakasiri, Dr. Udeni Nawagamuwa etc. for not only their contribution to improve my knowledge, but also for their guidance on my carrier success. Moreover, I would like to pay my gratitude to University of Moratuwa for providing me an opportunity to follow this Master degree and Management of Central Engineering Consultancy Bureau including Eng. K.L.S. Sahabandu, The General Manager, Eng. K.L.S.R. Sahabandu, The Additional General Manager and Dr. J.S.M Fowze, The Deputy General Manager for arranging sponsorship and relieving me from part of my duties and encouraging me for successfully completion of my master degree. Further, I extend my sincere thanks to all my colleagues in Royal Haskoning DHV, CHEC Port City Colombo (Pvt) Ltd. and China Harbour Engineering Company Ltd and Geotechnical Engineering Unit of CECB for their assistance and encouragement for completion of this thesis. Finally, Especially I must express my very profound gratitude to my loving mother for her dedications, encouragement and blessing for not only this work but also for my whole life. Further, my gratitude goes to my loving kids, Abiru and Theviru and wife, Pramila, for relieving me from part of my house works during this study. iii CASE STUDY: APPLICATION OF DYNAMIC AND VIBRO COMPACTION METHODS FOR DENSIFICATION OF GRANULAR FILL IN RECLAIMED LAND IN SRI LANKA ABSTRACT In the recent past, Government of Sri Lanka executed a large-scale reclamation project in Sri Lanka to add a brand-new land of 267-hectare to the Capital, Colombo with strategy of converting Colombo as a commercial hub of South Asia. For this project, 72 Million m3 of sea sand which was dredged by Trailing Suction Hopper Dredgers at 10km off from shore of Colombo was placed mainly by hydraulic methods at lower elevation while applying bulldozers at the top. This reclamation material was noted as clean uniform sand and which was under loose to medium dense condition prior to densification. This sand fill was densified using two methods, namely dynamic compaction and vibro compaction. Dynamic compaction, which is generally considered as one of the most economical sand improving methods, was applied in all areas except vibration sensitive areas at the city end and the areas where deep ground improvement was required for stability of earth retaining structures. Since settlement of subsoil in the seabed is not critical, the considered major geotechnical issues were achieving of required bearing capacity, shear strength and avoiding possible liquefaction. To sort out all geotechnical issues, sand densification was the only solution. Though there is a very long history for dynamic and vibro compaction methods, still reclamation projects are not pre- planned to utilize the self-compaction achieves during sand placing very effectively, while designs always follow a very conservative approach. Moreover, designs are carried out using pre-defined energy criterions rather than considering existing fill material properties and its pre-compaction condition. Thus, there was a paramount requirement to assess the dynamic and vibro compaction methods for Sri Lankan fill materials and reclamation methods with the intention of optimization of the above compaction methods. In order to optimize dynamic compaction method, the pre-and post-compaction condition (by CPTs) was evaluated by crater depth, net volume changes, influenced depth and related indices, which assess the degree of improvement based on applied iv energy. Similarly, densification by vibro compaction was evaluated with respect to the factor such as point spacing, amperage and compaction holding time. In addition, effect such as age of the compacted fill was considered for both dynamic and vibro compaction in this reclamation fill of clean sand. Finally, verification of densified ground by selecting CPTs at least compacted points with respect to the compaction grids was assessed for both dynamic and vibro compaction to confirm the optimization has no adverse effect on the final design. Based on the finding of this research, fill material’s index properties of Sri Lankan sea sand were determined while being noted that there is no hesitation for applicability of dynamic and vibro compaction for densification. During the analysis it was suggested to modify some correlations derived based on laboratory test data to achieve more realistic output for actual reclamation condition. In addition, design of dynamic and vibro compaction by performance-based method through trial compaction was discussed. Key words; Dredging, Dynamic Compaction, Vibro Compaction, Crater Depth, Influence Depth, Ground Improvement Index, Amperage, Compaction Time, Applicability, Verification, Optimization v CONTENTS ABSTRACT ................................................................................................................................................ iii 1. INTRODUCTION ............................................................................................................................... 1 1.1. General ......................................................................................................................................... 1 1.2. Background ................................................................................................................................... 1 1.3. Objectives of the Research .......................................................................................................... 2 1.4. Scope of Work .............................................................................................................................. 3 1.5. Outline of the Thesis ..................................................................................................................... 3 2. LITERATURE REVIEW................................................................................................................... 5 2.1. Off-Shore Reclamation Methods using Sea Sand ....................................................................... 5 2.2. Index Properties of Reclaimed Sea Sand ..................................................................................... 7 2.3. Potential Failure Modes in Reclaimed Land fill ........................................................................... 9 2.4. Scope of the Improvement in Reclaimed Ground ....................................................................... 9 2.5. Factors Affecting on the Popularity of Application and Improvements of Efficiency in Sand Densification work ................................................................................................................................. 10 2.6. Improvement of Fill Material ..................................................................................................... 11 2.7. Design and Acceptance Criteria ................................................................................................. 11 2.8. Parameters Related to Granular Soil Densification .................................................................. 12 2.8.1 Relative Density .................................................................................................................. 12 2.8.2 Compaction Status of Sand fill by Relative Density .......................................................... 15 2.9. Assessment of Potential Liquefaction ....................................................................................... 16 2.9.1 Soil Behaviour Type (SBT) Index (Ic) and Normalized Cone Resistance (Qtn) ................. 17 2.10. Methods Apply for Improvement of Reclaimed Sand Fill ..................................................... 19 2.11. Dynamic compaction .............................................................................................................. 20 2.11.1 Applicability of Dynamic Compaction ............................................................................... 21 2.11.2 Main Component of Dynamic Compaction Machine ........................................................ 24 2.12. Vibro Compaction ................................................................................................................... 24 vi 2.12.1. Applicability of Vibro Compaction ..................................................................................... 25 2.12.2. Use of Brown’s suitability index ........................................................................................ 27 2.12.3. Main component of the Deep Vibrators ........................................................................... 27 2.13. Mechanism of Densification in DC and VC ............................................................................ 29 2.14. Compaction Sequence of Dynamic Compaction ................................................................... 32 2.15. Construction Sequence of Vibro Compaction ....................................................................... 33 2.16. Optimization of Sand Densification ....................................................................................... 37 2.16.1. Factors Affecting Dynamic Compaction ............................................................................ 37 2.16.2. Factors Affecting Vibro Compaction .................................................................................. 40 2.16.3. Evaluation of Optimization of Sand Densification for Optimization ................................ 46 Influence Depth .................................................................................................................................. 52 Ground Improvement Index (Id) ........................................................................................................ 55 2.16.4. Other Influencing Factors for Optimization of Sand Densification .................................. 64 2.16.5. Evaluation of Densification ................................................................................................ 66 3. METHODOLOGY ........................................................................................................................... 69 4. RESULTS AND DISCUSSION ....................................................................................................... 72 4.1. Evaluation of Properties and Self-Compaction of Sand While Being Reclaimed by Different Methods. ................................................................................................................................................. 72 4.1.1. Index Properties of Reclaimed Sand .................................................................................. 72 4.1.2. Self-Densification during Reclamation .............................................................................. 73 4.1.3. Evaluation of the Properties of Dredged Sand .................................................................. 75 ................................................................................................................................................................. 77 4.2. Evaluation of the effectiveness of Dynamic and Vibro Compaction of the Reclaimed Sea Sand Fill 77 4.2.1. Application of Dynamic and Vibro Compaction ................................................................ 77 4.2.2. Applicability of Dynamic Compaction for the Project ....................................................... 78 4.2.3. Applicability of Vibro Compaction ..................................................................................... 79 4.2.4. Evaluation of Dynamic Compaction in Reclaimed Sea Sand for Optimization ................ 80 4.2.5. Evaluation of the Effectiveness of Vibro Compaction in Reclaimed Sea Sand for Optimization ..................................................................................................................................... 102 4.2.6. Ageing Effect on Sand Densified by DC and VC ............................................................... 109 vii 4.3. Evaluation of Ground Improvement Achieved in Dynamic and Vibro Compaction by CPT .. 109 4.3.1. Selection of CPT Locations ............................................................................................... 109 4.3.2. Summary of CPTs Advanced with Respect to the Vibro Compaction Points ................. 114 5. CONCLUSIONS ............................................................................................................................. 117 REFERENCES ........................................................................................................................................ 121 A1. APPENDIX I: Analysis for Properties of Fill Material and Self-Compaction While Placing I A1.1 Summary of qc values in Pre-compaction CPT .............................................................................. I A1.1. Variation of relative density by different methods ................................................................ II A2. APPENDIX II: Crater Depth Analysis ...................................................................................... III A3. APPENDIX III: Net Volume Change Analysis at Dynamic Compaction Point ...................... VI A4 APPENDIX IV: Influence Depth and the Parameter “n” For Permanent DC Work ............. X A5 Appendix V: Evaluation of Vibro Compaction ...................................................................... XIII A5.1 Trial VC Compaction .................................................................................................................. XIII A5.2 Evaluation of Compaction (qc) at Centroid of Three Surrounding Compaction Points with Respect to the Amperage Applied ........................................................................................................ XIV A6 APPENDIX VI: Cone Resistance (qc) Variation at Different Locations with Respect to the Compaction Point ................................................................................................................................... XIX A6.1 In 2000kNm dynamic compaction area .................................................................................... XIX A6.2 In 4000kNm- dynamic compaction area ................................................................................. XXIII A6.3 In vibro compaction area ........................................................................................................ XXIV A7 APPENDIX VII: Age Effect on Sand Densification .......................................................... XXVIII A7.1 Age effect on Dynamic Compaction ..................................................................................... XXVIII A7.2 Age effect when sand compacted by Vibro Compaction ....................................................... XXXI viii LIST OF FIGURES Figure 2-1: Sand bottom dumping from TSHD ............................................................................................ 5 Figure 2-2: Sand Rain bowing from TSHD .................................................................................................. 5 Figure 2-3: Sand pumping from TSSD ......................................................................................................... 7 Figure 2-4: Sand dumping and moving by earth movers .............................................................................. 7 Figure 2-5: Non-normalized SBT chart based on dimensionless cone resistance, (qc/pa) and friction ratio, Rf [10] .......................................................................................................................................................... 8 Figure 2-6: Soil identification of backfill for DC improvement (after Massarch 1991) [11] ....................... 8 Figure 2-7: Potential of liquefiable with grain size distribution of soils (Y. Tan 2005) [8] ......................... 9 Figure 2-8: emax and emin (for Nevada 50/80 sand) variation against non-plastic fines percentage (Redrawn from Lade et al 1998) .................................................................................................................................. 13 Figure 2-9: Relation between emax and e min ................................................................................................ 13 Figure 2-10: CRR vs qc1 for different soil types [26] .................................................................................. 16 Figure 2-11: Qtn vs Ic graph (Robertson: 2016) [19] ................................................................................... 18 Figure 2-12: Suitability of different ground stabilization methods varies grading range of problem soils (Mitchell et al., 1998) [9] ............................................................................................................................ 19 Figure 2-13: Schematic Illustration of deep dynamic compaction (Lukas:1995) [37] ............................... 21 Figure 2-14: Grouping of soils for dynamic compaction (Lukas, 1986) [36] ............................................. 22 Figure 2-15: Application range of the deep vibratory compaction techniques and liquefiable soils range (Keller; 2012) [48] ...................................................................................................................................... 26 Figure 2-16: Vibrator Motion and Schematic ............................................................................................. 28 Figure 2-17: Profile of sand grains rearranged by dynamic compaction .................................................... 30 Figure 2-18: Axial deformation of confined compactable loose granular soil [54] .................................... 30 Figure 2-19: Wave Propagation due to dynamic compaction (Wood R.D) [55] ........................................ 30 Figure 2-20: Soil Improvement Descriptive Pattern of by DC (Lukas, 1986) [36] .................................... 31 Figure 2-21: Grain rearrangement in Vibro Compaction ............................................................................ 31 Figure 2-22: Arrangement of compaction point as first and second pass ................................................... 32 Figure 2-23: Treatment by each pass .......................................................................................................... 32 Figure 2-24: Dynamic compaction done in the project site ........................................................................ 33 Figure 2-25: Construction sequence of vibro compaction .......................................................................... 34 Figure 2-26: Process of vibro-compaction and its affection zone ............................................................... 35 Figure 2-27: Densification zones resulting from vibrocompaction (Brown: 1977) .................................... 36 Figure 2-28: Vibro Compaction done in Project Area ................................................................................ 36 Figure 2-29: Corelation of tamper mass and drop height (Mayne et al.1984) ............................................ 39 Figure 2-30: Tributary Areas variation with point pattern .......................................................................... 42 Figure 2-31: Approximate post-compaction relative density variation with tributary area per compaction point (Dobson and Slocombe:1982) [62] .................................................................................................... 42 Figure 2-32: Tip resistance (qc) variation of post- treated CPT with distance from compaction point for two different vibrators (Degan and Hussain: 2001) [62] ............................................................................ 43 Figure 2-33: Illustration of vibro float induced the horizontal impacting forces and torsional shear (Green wood :1991) ................................................................................................................................................ 44 Figure 2-34: Verification of Numerical Model with Experimental Data of Arslan et al. (2007) [66] ........ 48 ix Figure 2-35: Nnormalized crater depth Correlation with drop numbers measured from model test by F. Jafarzadeh and the Equation introduced by Takada and Oshima for different compaction energy levels. [69] .............................................................................................................................................................. 49 Figure 2-36: Computed and measured crater depths at Nishiro site [70].................................................... 50 Figure 2-37: Relation between normalized crater depth and √N ................................................................ 51 Figure 2-38: Corelation between square root of energy per drop and influence depth (after Leonards et al. 1980) [72] ................................................................................................................................................... 52 Figure 2-39: Depth improvement as measured at 3m from centre of drop point (Lukas (1995)) [44] ....... 52 Figure 2-40: Depth improvement as measured at 6.1m from centre of drop point (Lukas (1995)) [44] .... 52 Figure 2-41: Typical Energy -Depth of influence chart for DC (Slocombe, 1993) [75] ............................ 54 Figure 2-42: Relationship between improvement depth and normalized compaction energy [69] ........... 55 Figure 2-43: Typical Id graph with respect to the pass number (Y. Tan et al.2007) [8] ............................. 55 Figure 2-44: Varition the vibrator depth, current power consumption of the electric engine, vibrator tip amplitude, angle of phase and pull-down pressure during deep vibrator compaction against time under standard operation mode (Nagy et al. 2017) [80] ....................................................................................... 57 Figure 2-45: position of eccentric mass with respect to the vibrator contact location ................................ 58 Figure 2-46: Recorded lateral movement of the tip of vibro probe at the commencement (left) and at the end (right) in the lowering process during the highlighted compaction step in Figure 2-44 ...................... 59 Figure 2-47: Soil Response of vibro-floatation (civildigital.com) [80] ...................................................... 59 Figure 2-48: Current log recorded during vibro compaction (Degan and Hussin 2001) ............................ 60 Figure 2-49: Variation of PPV measured in different distance with respect to the depth (Babak: 2011) ... 63 Figure 2-50: Compaction evolution in time of vibration at a point ............................................................ 63 Figure 2-51: Influence of period of sustained pressure on stress ratio causing peak cyclic pore pressure ratio of 100% ( [88] ..................................................................................................................................... 64 Figure 2-52: Effect of time upon relative improvement in CPT values in sandy soil in ............................ 65 Figure 2-53: Sum of coefficients of influence at critical point for triangular spacing pattern .................... 68 Figure 3-1: Flow chart of research .............................................................................................................. 71 Figure 4-1: Soil behaviour of filling material in this project as per SBT chart by Robertson et al. (2010) prepared based on pre-compaction CPT data.............................................................................................. 72 Figure 4-2: qc range in pre-compaction CPT curves .................................................................................. 74 Figure 4-3: Maximum and minimum DR values varies with depth in pre-compaction CPTs ..................... 74 Figure 4-4: SBT chart for dredge sand with compactability envelope. ...................................................... 75 Figure 4-5: Grain size distribution of sand used for port city reclamation. ................................................ 76 Figure 4-6: Ic Vs Qtn graph for pre-compaction reclaimed sand ................................................................. 77 Figure 4-7: Ground Improvement Areas compacted by different san densification methods .................... 78 Figure 4-8: Applicability of dynamic compaction and vibro compaction. ................................................. 78 Figure 4-9: Sand behavior within Lukas’ Grouping of soils for dynamic compaction ............................... 79 Figure 4-10: Particle distribution curves range of this reclaimed sand in Keller envelope for vibro compaction .................................................................................................................................................. 79 Figure 4-11: Application of dynamic compaction ...................................................................................... 81 Figure 4-12: Typical pounder used for dynamic comaction ....................................................................... 82 Figure 4-13: Typical dynamic compaction machine used in Port City project ........................................... 82 Figure 4-14: Compaction point arrangement for Trial dynamic compaction by 4000 kNm and 2000kNm .................................................................................................................................................................... 82 Figure 4-15: Ironing tamping pattern in 4000kNm and 2000kNm applied area. ........................................ 83 x Figure 4-16: compaction pattern in 1000 kNm energy applied area ........................................................... 83 Figure 4-17: typical crater seen during dynamic compaction ..................................................................... 84 Figure 4-18: Crater depth variation with blow number .............................................................................. 85 Figure 4-19: Increment in crater depth with respect to blow number ........................................................ 85 Figure 4-20; comparison of crater depth found from modified Takada equation. ...................................... 87 Figure 4-21: Normalized Crater Depth Vs Blow Number (N).................................................................... 88 Figure 4-22: Normalized crater depth variation with √N ............................................................................ 89 Figure 4-23: liner variation between Normalized crater depth and √N ...................................................... 90 Figure 4-24: Ground level measured point in perpendicular directions at dynamic compaction point ...... 91 Figure 4-25: Net volume variation with blow number ................................................................................ 91 Figure 4-26: Net volume increment variation with no of blow .................................................................. 92 Figure 4-27: Comparison in influence depth considering improvement in qc after applying DC .............. 93 Figure 4-28: CPT locations in 4000kNm applied area................................................................................ 94 Figure 4-29: CPT locations in 2000kNm applied area................................................................................ 95 Figure 4-30: Variation of influence depth with √WH for this study ........................................................... 95 Figure 4-31: influenced depth variation with √WH in this study along with previous studies data ........... 96 Figure 4-32: Influenced depth variation with square root of energy........................................................... 97 Figure 4-33: Ground Improvement Index variation with depth in trial area of this study .......................... 98 Figure 4-34: Variation of Ground Improvement Index upon target with depth in trial area ...................... 99 Figure 4-35: qt-target /qt- pre ........................................................................................................................... 101 Figure 4-36: Target qc plotted along with minimum qc values in pre-compaction CPT .......................... 101 Figure 4-37: layout of trial points ............................................................................................................. 102 Figure 4-38: Comparison of achieved compaction (qc) for different point spacing .................................. 103 Figure 4-39 : Average compaction (qc)variation with different spacing .................................................. 104 Figure 4-40: Typical time and amperage consumption curve ................................................................... 105 Figure 4-41: Amperage consumption (right) and time consumption (left) with elevation in compaction phase ......................................................................................................................................................... 106 Figure 4-42: Amperage variation during compaction ............................................................................... 107 Figure 4-43: Cumulative amperage applied within considered elevation ................................................. 107 Figure 4-44: Advanced CPT locations with respect to the compaction points ......................................... 110 Figure 4-45: Comparison of qc curves in 2000kNm DC applied area with respect to the compacted points .................................................................................................................................................................. 111 Figure 4-46: Effect of laterally influenced zone in dynamic compaction ................................................. 112 Figure 4-47: Average qc values of CPT conducted at centroid of nearby compaction points in 4000kNm applied area ............................................................................................................................................... 113 Figure 4-48: achieved qc improvement in 2000kNm and 4000kNm applied dynamic compaction areas 113 Figure 4-49: Selection of CPT location with respect to the nearby vibro compaction point .................... 114 Figure 4-50: qc variation with CPT location with respect to the compaction point ................................. 115 Figure 4-51: Possible variation in laterally influenced zones with change of grid spacing ...................... 116 Figure A- 1: Pre-compaction CPT Results .................................................................................................... I Figure A- 2: Variation of DR before compaction by (a) Biryaltseva method (b) Mayne method (c) Tom Lunee method................................................................................................................................................ II Figure A- 3: Cumulative crater depth variation with blow number ............................................................. III xi Figure A- 4: Normalized crater depth variation with square root of blow number in 1st pass of 2000kNm III Figure A- 5: Normalized crater depth variation with square root of blow number in 2nd pass of 2000kNm ..................................................................................................................................................................... IV Figure A- 6: Normalized crater depth variation with square root of blow number in 1st pass of 4000kNm IV Figure A- 7: Normalized crater depth variation with square root of blow number in 2nd pass of 4000kNm ...................................................................................................................................................................... V Figure A- 8: Average normalized crater depth Vs √N .................................................................................. V Figure A- 9: Crater, heave and net volume variation at A2 point in 4000kNm DC area for 1st pass .......... VI Figure A- 10: Crater, heave and net volume variation at G2 point in 4000kNm DC area for 1st pass ........ VI Figure A- 11: Crater, heave and net volume variation at B1 point in 4000kNm DC area for 2nd pass ....... VII Figure A- 12: Crater, heave and net volume variation at B7 point in 4000kNm DC area for 2nd pass ....... VII Figure A- 13: Crater, heave and net volume variation at F1 point in 4000kNm DC area for 2nd pass ....... VII Figure A- 14: Crater, heave and net volume variation at J7 point in 4000kNm DC area for 2nd pass ....... VIII Figure A- 15: Crater, heave and net volume variation at I2 point in 2000kNm DC area for 1st pass ........ VIII Figure A- 16: Crater, heave and net volume variation at M2 point in 2000kNm DC area for 1st pass ...... VIII Figure A- 17: Crater, heave and net volume variation at L3 point in 2000kNm DC area for 2nd pass ........ IX Figure A- 18: Average net volume variation ............................................................................................... IX Figure A- 19: Net volume increment in ground movement by DC ............................................................. IX Figure A- 20: Typical Amperage usage in nearest VC points ................................................................... XIII Figure A- 21: (a) Applied amperage (b) Applied average cumulative amperage at each elevation (c) qc variation in the depth at C93 ...................................................................................................................... XIV Figure A- 22:(a) Applied amperage (b) Applied average cumulative amperage at each elevation (c) qc variation in the depth at C95 ...................................................................................................................... XIV Figure A- 23: (a) Applied amperage (b) Applied average cumulative amperage at each elevation (c) qc variation in the depth at C97 ....................................................................................................................... XV Figure A- 24: (a) Applied amperage (b) Applied average cumulative amperage at each elevation (c) qc variation in the depth at C102 ..................................................................................................................... XV Figure A- 25: (a) Applied amperage (b) Applied average cumulative amperage at each elevation (c) qc variation in the depth at AC6 ..................................................................................................................... XVI Figure A- 26: a) Applied amperage (b) Applied average cumulative amperage at each elevation (c) qc variation in the depth at AC29 ................................................................................................................... XVI Figure A- 27: a) Applied amperage (b) Applied average cumulative amperage at each elevation (c) qc variation in the depth at AC30 .................................................................................................................. XVII Figure A- 28: a) Applied amperage (b) Applied average cumulative amperage at each elevation (c) qc variation in the depth at AC384 ................................................................................................................ XVII Figure A- 29: a) Applied amperage (b) Applied average cumulative amperage at each elevation (c) qc variation in the depth at AC386 ............................................................................................................... XVIII Figure A- 30: Average qc at centroid w.r.t compaction point in 2000kNm DC Area ............................... XIX Figure A- 31: Average qc at centre w.r.t to compaction points in 2000 DC area ....................................... XX Figure A- 32: qc curves at 1m away from DC points. ............................................................................... XXI Figure A- 33: qc curve at mid of two 2000kNm DC point ........................................................................ XXII Figure A- 34: qc at centroid w.r.t. compaction points in 4000kNm DC area .......................................... XXIII Figure A- 35: qc variation at centroid w.r.t. the VC points ..................................................................... XXIV Figure A- 36: qc at mid of two VC points ................................................................................................ XXV Figure A- 37: qc variation at centre of VC point ..................................................................................... XXVI xii Figure A- 38; qc variation at 1m away from a centre of VC point .......................................................... XXVII Figure A- 39: qc variation when compaction below 2 months .............................................................. XXVIII Figure A- 40: Variation of qc when compaction below 180 days .......................................................... XXIX Figure A- 41: Variation of qc when compaction above 200 days ............................................................ XXX Figure A- 42: Variation of qc in different ages ........................................................................................ XXXI xiii LIST OF TABLES Table 2-1: Typical relative densities as a result of hydraulic fill [5] ............................................................ 6 Table 2-2: Soil Types identified by SBT ...................................................................................................... 8 Table 2-3: Qualitative Description in compaction for Granular Soil Deposits ........................................... 15 Table 2-4: Suitability of soil for dynamic compaction (Lukas, 1986) ........................................................ 23 Table 2-5: Effectiveness of vibrocompaction with soil types (Courtesy; Keller) [48] ............................... 26 Table 2-6: Rating for vibrocompaction on SN (Brown: 1977) [49] ............................................................. 27 Table 2-8: Guidelines on applied Energy for densifying various soils (Lukas 1986) ................................. 40 Table 2-9: Specifications of several vibrators (Degen and Hussin 2001) [62] ........................................... 41 Table 2-10: Values of n for various pounders (after Choa et al ; 1997 [1]) ............................................... 54 Table 4-1: grading indices of reclaimed sand ............................................................................................. 73 Table 4-2: Pounder details .......................................................................................................................... 80 Table 4-3: Design of Dynamic compaction ................................................................................................ 81 Table 4-4: Summary of influence depth with respect to the applied energy and estimated n values ......... 94 Table 4-5: Target qc values applied in different areas of this project ....................................................... 100 Table 4-6: Summary of repeated CPTs ..................................................................................................... 109 Table 4-7: Summary of advanced CPTs with respect to the compaction points in 2000kNm DC area. .. 111 Table 4-8 : Summary of CPT advanced with respect to the compaction points ....................................... 115 Table A- 1: Influence depth assessed from CPT results in 4000kNm energy applied area. ......................... X Table A- 2: Influence depth assessed from CPT results in 2000kNm energy applied area. ........................ XI xiv LIST OF ABBREVIATIONS Abbreviation Description TSHD Trailer Suction Hopper Dredger (D)DC (Deep) Dynamic Compaction VC Vibro Compaction CPT Cone Penetration Test SPT Standard Penetration Test SBT Soil Behaviour Type MDD Maximum Dry Density CC Calibration Chamber NC Normal Consolidation CRR Cyclic Resistant Ratio CSR Cyclic Stress Ratio PPV Peak Particle Velocity PGA Peak Ground Acceleration