An Approach to design criteria for long -span floating bridges MÀSTER Treball realitzat per: Gerard-Josep Alcalde Gascón Dirigit per: Joan Ramon Casas Rius Climent Molins Borrell Màster en: Enginyeria de Camins, Canals i Ports Barcelona, 26 de Juny de 2020 Departament d’Enginyeria Civil i Ambiental PQ3W9G0723554900108970J TREBALL FINAL DE FINAL TREBALL GERARD-JOSEP ALCALDE GASCÓN AN APPROACH TO DESIGN CRITERIA FOR LONG-SPAN FLOATING BRIDGES Index INDEX ................................................................................................................................................... I INDEX OF TABLES ................................................................................................................................ III INDEX OF FIGURES ............................................................................................................................... V ACKNOWLEDGMENTS ......................................................................................................................... IX ABSTRACT ........................................................................................................................................... X RESUMEN ........................................................................................................................................... XI RESUM .............................................................................................................................................. XII 1. INTRODUCTION ........................................................................................................................... 1 2. OBJECTIVES ................................................................................................................................. 2 3. STATE OF THE ART ....................................................................................................................... 3 3.1. BRIDGES IN DEEP WATER AREAS .......................................................................................................... 3 3.1.1. Introduction ....................................................................................................................... 3 3.1.2. Offshore engineering ......................................................................................................... 3 3.2. BRIDGE SOLUTIONS FOR DEEP WATERS ................................................................................................. 7 3.2.1. Suspension bridges ............................................................................................................ 8 3.2.2. Floating bridges ............................................................................................................... 11 3.2.3. Floating suspension or cable-stayed bridge ..................................................................... 12 3.2.4. Pontoon bridge combined with a cable stayed bridge .................................................... 15 3.2.5. Pontoon bridge combined with a submerged floating tunnel at mid-fiord ..................... 15 3.3. PLACES REQUIRING A SOLUTION FOR DEEP WATER CROSSINGS ................................................................ 16 3.3.1. The E39 project ................................................................................................................ 16 3.3.2. The Messina strait ........................................................................................................... 18 3.3.3. Scotland and Northern Ireland bridge ............................................................................. 19 3.4. CONCLUSIONS .............................................................................................................................. 21 4. TECHNOLOGY COMPARISON AND ALTERNATIVE SELECTION. A CASE STUDY ............................. 22 4.1. INTRODUCTION ............................................................................................................................. 22 4.2. STUDY SPECIFICATIONS AND DESIGN ASSUMPTIONS .............................................................................. 22 4.3. SOGNEFJORD INFORMATION ............................................................................................................ 23 4.3.1. Physical data .................................................................................................................... 24 4.3.2. Meteorological data ........................................................................................................ 24 4.3.3. DecK section ..................................................................................................................... 29 4.3.4. Extreme events ................................................................................................................ 30 4.4. BRIDGE LAYOUT ............................................................................................................................ 31 4.4.1. Cable-stayed bridge ......................................................................................................... 31 4.4.2. Suspension bridge ............................................................................................................ 33 4.5. PRELIMINARY BRIDGE DESIGN .......................................................................................................... 34 4.5.1. General considerations for both designs ......................................................................... 34 4.5.2. Cable-stayed bridge ......................................................................................................... 41 4.5.3. Suspension bridge ............................................................................................................ 52 4.6. PRELIMINARY PONTOON DESIGN ....................................................................................................... 59 4.6.1. Evaluation of the loads at the pontoons .......................................................................... 60 4.6.2. Tension leg platform (TLP) ............................................................................................... 75 4.6.3. Tethered spar-buoy .......................................................................................................... 82 4.6.4. Anchoring ........................................................................................................................ 89 I GERARD-JOSEP ALCALDE GASCÓN AN APPROACH TO DESIGN CRITERIA FOR LONG-SPAN FLOATING BRIDGES 4.7. ECONOMIC COMPARISON OF THE ALTERNATIVES .................................................................................. 95 4.8. DISCUSSION ................................................................................................................................. 96 4.8.1. Conclusions obtained from the other alternatives ........................................................... 98 4.8.2. Design criteria for long-span floating bridges ............................................................... 100 5. CONCLUSIONS .......................................................................................................................... 101 5.1. FUTURE RESEARCH LINES ............................................................................................................... 103 6. REFERENCES ............................................................................................................................. 104 ANNEX 1. OPTIMIZATION OF THE SPAR-BUOY ANCHOR POSITION .................................................... 109 ANNEX 2. ALTERNATIVE BLUEPRINTS ................................................................................................ 131 II GERARD-JOSEP ALCALDE GASCÓN AN APPROACH TO DESIGN CRITERIA FOR LONG-SPAN FLOATING BRIDGES Index of tables Table 1: Load coefficients ........................................................................................................... 23 Table 2: Material coefficients ..................................................................................................... 23 Table 3: Current data for a return period of 50 years ................................................................ 24 Table 4: Wave parameters ......................................................................................................... 25 Table 5: Tower-span ratio of the longest cable-stayed bridges ................................................. 32 Table 6: Results cable dimensioning for cable-stayed bridge ..................................................... 44 Table 7: Results cable prestressing force for cable-stayed bridge ............................................. 45 Table 8: Area needed in the tower to bear the axial forces in the cable-stayed bridge ............ 46 Table 9: Design of the towers for the cable-stayed bridge ........................................................ 47 Table 10: Loads transferred to the platform .............................................................................. 47 Table 11: Longitudinal and transversal stiffeners design. Measures in mm .............................. 49 Table 12: Volume of the different parts. Cable-stayed bridge with steel pylons ....................... 50 Table 13: Volume of the different materials. Cable-stayed bridge with steel pylons ................ 51 Table 14: Weight of the different materials. Cable-stayed bridge with steel pylons ................. 51 Table 15: Volume of the different parts. Cable-stayed bridge with concrete pylons