Behaviour and Design of EXTRADOSED BRIDGES by Konstantinos Kris Mermigas A thesis submitted in conformity with the requirements for the degree of Master of Applied Science Graduate Department of Civil Engineering University of Toronto © Copyright by Konstantinos Kris Mermigas (2008) ii Behaviour and Design of Extradosed Bridges Konstantinos Kris Mermigas Master of Applied Science Graduate Department of Civil Engineering University of Toronto 2008 ABSTRACT The purpose of this thesis is to provide insight into how different geometric parameters such as tower height, girder depth, and pier dimensions influence the structural behaviour, cost, and feasibility of an extradosed bridge. A study of 51 extradosed bridges shows the variability in proportions and use of extradosed bridges, and compares their material quantities and structural characteristics to girder and cable-stayed bridges. The strategies and factors that must be considered in the design of an extradosed bridge are discussed. Two cantilever constructed girder bridges, an extradosed bridge with stiff girder, and an extradosed bridge with stiff tower are designed for a three span bridge with central span of 140 m. The structural behaviour, materials utilisation, and costs of each bridge are compared. Providing stiffness either in the girder or in the piers of an extradosed bridge are both found to be effective stategies that lead to competitive designs. iii ACKNOWLEDGEMENTS I would like to thank Professor Gauvreau for the opportunity to study under his guidance and be part of a dynamic and ambitious bridge research group. Professor Gauvreau has served as an inspiration and mentor to me in my career. Thanks to my research colleagues for their insightful discussions and feedback: Mike Montgomery, Jimmy Susetyo, Ivan Wu, Jeff Erochko, Lydell Wiebe, Brent Visscher, Jamie McIntyre, Lulu Shen, Eileen Li, Sandy Poon, Davis Doan, and especially Jason Salonga. Finally, thanks to my family and Mary Jane for encouraging and supporting me through my graduate studies. iv TABLE OF CONTENTS ii A BSTRACT iii A CKNOWLEDGEMENTS iv T ABLE OF C ONTENTS viii L IST OF F IGURES xiii L IST OF T ABLES 1 1 W HAT M AKES A B RIDGE E XTRADOSED ? 1 1.1 Introduction 2 1.2 Objectives and Scope 3 1.3 Historical Context 13 1.4 General Studies on Extradosed Bridges 15 2 R EVIEW OF E XISTING E XTRADOSED B RIDGES 15 2.1 Study of Extradosed Bridges 15 2.2 Trends in Extradosed Bridges to Date 29 2.3 Characteristics of Extradosed Bridges 29 2.3.1 Materials Usage 31 2.3.2 Girder Stiffness 32 2.4 Detailed Descriptions of Extradosed Bridges 32 2.4.1 Odawara Port Bridge, Japan 33 2.4.2 Tsukuhara Extradosed Bridge, Japan 34 2.4.3 Ibi and Kiso River Bridges, Japan 35 2.4.4 Shin-Meisei Bridge, Japan 36 2.4.5 North Arm Bridge, Canada 37 2.4.6 Pont de Saint-Rémy-de-Maurienne, France 38 2.4.7 Viaduc de la ravine des Trois Bassins, Réunion 38 2.4.8 Sunniberg Bridge at Klosters, Switzerland 40 2.5 Concluding Remarks v 41 3 D ESIGN AND C ONSTRUCTION OF E XTRADOSED B RIDGES 41 3.1 Loads 41 3.1.1 Live Load 44 3.1.2 Temperature 46 3.2 Design Concepts 46 3.2.1 Stiffness of Cables and Girder 48 3.2.2 Stiffness of Superstructure and Substructure 50 3.2.3 Prestressing Methodology 52 3.3 Conceptual Design 52 3.3.1 Fixity of the Girder to the Piers 53 3.3.2 Side Span Length 53 3.3.3 Tower Height and Girder Depth 56 3.4 Stay Cables and Anchorages 56 3.4.1 Cable Arrangement 60 3.4.2 Stay Cable Protection 60 3.4.3 Anchorages in Girder 61 3.4.4 Cable Anchorage in Towers: Saddles or Anchorages? 64 3.4.5 Equivalent Modulus of Elasticity for Stay Cables 65 3.4.6 Preliminary Design of Stay Cables at Serviceability Limit States 67 3.4.7 Verification of Stay Cables at the Fatigue Limit State 68 3.4.8 Verification of Stay Cables at Ultimate Limit States 69 3.4.9 Stay Cable Tensioning 74 3.5 Towers and Piers 75 3.6 The Girder Cross-Section 76 3.6.1 Centrally Supported Box Girder Cross-Section 78 3.6.2 Laterally Supported Single Cell Box Girder Cross-Section 78 3.6.3 Multiple Cell Box Girder Cross-Section 80 3.6.4 Laterally Supported Stiffened Slab Cross-Section 81 3.6.5 Composite Cross-Section 82 3.7 Tendon Layout 83 3.8 Erection 85 3.9 Verification at the Ultimate Limit States 86 3.10 Concluding Remarks vi 88 4 D ESIGN OF C ANTILEVER C ONSTRUCTED G IRDER B RIDGE , E XTRADOSED B RIDGE WITH S TIFF G IRDER , AND E XTRADOSED B RIDGE WITH S TIFF TOWER 89 4.1 Design Assumptions 89 4.1.1 Material Properties and Detailing 90 4.1.2 Analysis and Limit States Verification 91 4.1.3 Temperature Gradient 92 4.1.4 Construction Sequence and Segment Construction Cycle 93 4.2 Cantilever Constructed Girder Bridge 93 4.2.1 Layout and Cross-Section 93 4.2.2 Longitudinal Prestressing 96 4.2.3 Verification at SLS and ULS 97 4.3 Extradosed Bridge with Stiff Deck 97 4.3.1 Layout and Cross-Section 98 4.3.2 Longitudinal Prestressing 100 4.3.3 Comparison with Bending Moments in a Girder Bridge 102 4.3.4 Detailed Model 102 4.3.5 Verification at SLS and ULS 104 4.4 Extradosed Bridge with Stiff Tower 104 4.4.1 Layout and Cross-Section 106 4.4.2 Detailed Model 108 4.4.3 Verification at SLS and ULS 108 4.5 Design Comparison 108 4.5.1 Girder Cross-Section 109 4.5.2 Material Quantities 110 4.5.3 Cost Comparison 112 5 C ONCLUSIONS 112 5.1 Review of Extradosed Bridges 112 5.2 Design Considerations 113 5.3 Comparison between Extradosed and Cantilever Constructed Girder Bridges 114 6 R EFERENCES vii 122 D RAWINGS 123 CANT-S1. Cantilevered PT Bridge - General Arrangement 124 CANT-A-S2. Cantilevered PT Bridge, Mixed Tendons - P.T. Tendon Duct Locations 125 CANT-A-S3. Cantilevered PT Bridge, Mixed Tendons - P.T. Layout 126 CANT-B-S2. Cantilevered PT Bridge, Internal Tendons - P.T. Tendon Duct Locations & Typical Reinforcement 127 CANT-B-S3. Cantilevered PT Bridge, Internal Tendons - P.T. Layout 128 EXTG-S1. Extradosed Bridge, Stiff Girder - General Arrangement 129 EXTG-S2. Extradosed Bridge, Stiff Girder - P.T. Tendon Duct Locations & Typical Reinforcement 130 EXTG-S3. Extradosed Bridge, Stiff Girder - P.T. Layout 131 EXTT-S1. Extradosed Bridge, Stiff Tower - General Arrangement 132 EXTT-S2. Extradosed Bridge, Stiff Tower - P.T. Tendon Duct Locations & Typical Reinforcement 133 EXTT-S3. Extradosed Bridge, Stiff Tower - P.T. Layout 134 A PPENDIX A Chapter 2 Supplementary Information 139 A PPENDIX B Chapter 4 Supporting Calculations 140 B.1 Girder Bridge Preliminary PT Design A - Mixed Tendons 144 B.2 Girder Bridge PT Design A - Detailed Model SLS Stress Checks 145 B.3 Girder Bridge PT Design A - Detailed Model ULS Moment Capacity Check 146 B.4 Girder Bridge Preliminary PT Design B - Internal Tendons 150 B.5 Girder Bridge PT Design B - Detailed Model SLS Stress Checks 151 B.6 Girder Bridge PT Design B - Detailed Model ULS Moment Capacity Check 152 B.7 Stiff Girder Extradosed Bridge PT Design - Detailed Model SLS Stress Checks 153 B.8 Stiff Girder Extradosed Bridge PT Design - Detailed Model ULS Moment Capacity Check 154 B.9 Stiff Girder Extradosed Bridge - Cable Forces 155 B.10 Stiff Tower Extradosed Bridge PT Design - Detailed Model SLS Stress Checks 156 B.11 Stiff Tower Extradosed Bridge PT Design - Detailed Model ULS Moment Capacity Check 157 B.12 Stiff Tower Extradosed Bridge - Cable Forces 158 A PPENDIX C Chapter 4 Quantities 159 C.1 Breakdown of Prestressing Quantities of Chapter 4 Bridges 160 A PPENDIX D Presentation Handout viii LIST OF FIGURES 1 1 W HAT M AKES A B RIDGE E XTRADOSED ? 1 1-1 Comparison between cantilever-constructed girder, extradosed, and cable-stayed bridge types. 2 1-2 Finback, cable-panel and extradosed bridge types. 4 1-3 Ganter Bridge (Vogel & Marti 1997) 5 1-5 Barton Creek Bridge (Gee 1991). 5 1-4 Arrêt-Darré Viaduct (Mathivat 1988). 6 1-6 Odawara Blueway Bridge (Kasuga 2006). 7 1-7 Saint-Remy-de-Maurienne Bridge (photo by Jacques Mossot, Structurae). 7 1-8 Concept for Usses Viaduct (Virlogeux 2002b). 8 1-9 Santiago Calatrava’s concepts for crossing deep Alpine valleys. From left to right: Variant 1, Variant 2 model, Variant 7 sketch and detail presented by Menn at the IABSE Symposium in Zurich in 1979 (Calatrava 2004). 8 1-10 Response of cable-stiffened, girder-stiffened, and tower-stiffened cable-stayed bridge to live load. 9 1-11 Poya Bridge, Switzerland: a) Menn’s 1989 proposal (Menn 1996) and b) cable-stayed design selected in 2006 for construction (Mandataire Projet Poya 2005). 10 1-12 Millau Viaduct tower options (Virlogeux 2004). Drawn by Sir Norman Foster after discussions with Virlogeux. 11 1-13 Sunniberg Bridge, Switzerland. 11 1-14 Arrêt-Darré and Sunniberg Bridges (see drawings in Figure 2-1). 12 1-15 Golden Ears Hybrid Extradosed Bridge, Vancouver (Bergman 2007). 13 1-16 North Arm Bridge, Canada Line LRT, Vancouver (photo courtesy of Stephen Rees) 13 1-17 Pearl Harbor Memorial Bridge in New Haven, Connecticut (Stroh et al. 2003) 15 2 R EVIEW OF E XISTING E XTRADOSED B RIDGES 23 2-1 Drawings of extradosed bridges. 27 2-2 Extradosed Bridges separated span to depth ratio at a) pier and b) midspan. 28 2-3 Span to depth ratios of extradosed bridges at midspan and pier. 28 2-4 Haunching in extradosed bridges shown a) in groups by span length and b) as the pier to midspan depth ratio by span. 29 2-5 Span to tower height ratio of extradosed bridges. ix 30 2-6 Average girder concrete thickness of cantilever-constructed girder, extradosed and cable-stayed bridges. 30 2-7 Average girder concrete thickness of extradosed bridges. 31 2-8 Mass of steel in cantilever constructed girder bridges: a) longitudinal prestressing steel, and b) reinforcing steel (plots are based on data from SETRA 2007, Lacaze 2002, DEAL 1999). 32 2-9 Moment of inertia of girder at midspan for extradosed and cable-stayed bridges (per 10 m width). 33 2-10 Odawara Extradosed Bridge details of tower saddle and arrangement of prestressing bars in tower from FEM analysis (Kasuga et al. 1994). 33 2-11 Odawara Extradosed Bridge: a) strand supply system; b) saddle structure at the pier top, and c) anchorage structure at the main girder. (Toniyama & Mikami 1994). 34 2-12 Ibi River Bridge Prestressing Tendon Layout in Cross-Section (Kutsuna et al. 1999). 35 2-13 Nonlinear Behaviour of the Ibi River Bridge up to ultimate load (Kutsuna et al. 2002). 35 2-14 Shin-Meisei Birdge construction of side spans (Iida et al. 2002). 36 2-15 Shin-Meisei Birdge a) photo of steel shell of tower; b) elevation of composite tower and c) details of composite tower (drawings: Iida et al. 2002, photo and rendering: Kasuga 2006). 36 2-16 North Arm Birdge a) deck level extradosed cable anchorage; b) precast tower, and c) tower anchor segment (from Griezic et al. 2006). 38 2-17 Trois Bassins Viaduct main pier (Frappart 2005). 39 2-18 Sünniberg Bridge a) deck cross-section and b) prestressing and reinforcement (adapted from Tiefbauamt Graubünden 2001). 39 2-19 Anchorages in towers (adapted from Tiefbauamt Graubünden 2001). 39 2-19 Anchorages in towers (adapted from Tiefbauamt Graubünden 2001). 40 2-20 Sunniberg Bridge a) bending moments and deflections of the edge beam through one stage of construction, and b) forces and deflections of the main span inner edge beam of the final structure due to permanent and live loads (adapted from Figi et al. 1998). 41 3 D ESIGN AND C ONSTRUCTION OF E XTRADOSED B RIDGES 42 3-1 CL-625 Live Loading: Maximum of CL-625 Truck (including DLA) or CL-625 Lane Load. 42 3-2 ASCE Loading (adapted from Buckland 1981) 44 3-3 multiple lane loading effect by deck width according to CHBDC 2006 and ASCE 1981, for two planes of cables and for single plane central cable suspension. 45 3-4 Comparison of Temperature Gradients (adapted from Priestley 1978, AASHTO 2004). 52 3-5 CHBDC CL-625 Live load envelopes for a main span of 100 m. x 54 3-6 Comparison of span to depth ratio and effect of the roadway height above ground on the overall proportions of 3 span cantilever, extradosed, and cable-stayed bridges. 55 3-7 Extradosed bridge geometry studied by Chio Cho (2000). 55 3-8 Girder and extradosed bridge proportions recommended by others. 56 3-9 Bridge proportions used for design in Chapter 4. 57 3-10 Effect of cable inclination on the force components in a cable for a) a constant total force and b) a constant vertical force. 57 3-11 Quantity of cable steel as a function of relative height of towers - Comparison between fan and harp cable configurations in a) 1970 (Leonhardt & Zellner 1970) and b) 1980 (Leonhardt & Zellner 1980). 58 3-12 Quantity of cable steel as a function of relative height of towers - comparison between semi- fan and harp cable configurations for 140 m main span. 59 3-13 Influence of partial cable support (adapted from Tang 2007). 61 3-14 DSI Extradosed Anchorage Type XD-E (Dywidag 2006). 65 3-15 Ratio of equivalent to initial modulus of elasticity showing the influence of a cable’s sag on its stiffness (plot adapted from Leonhardt & Zellner 1970). 66 3-16 Allowable stress in cable stays as a function of the stress range due to live load at SLS 70 3-17 Cable pre-strain and maximum moments for 25 iterations of the zero displacement method applied in two staged process: a) towers fixed, main span cable strains adjusted and b) towers released and side span cable strains adjusted. Cable 1 is anchored closest to the pier. 72 3-18 Cable force corresponding to dead load moment distribution (adapted from Gimsing 1997). 73 3-19 Tensions of main span cables, at each stage of construction up to midspan closure, resulting from a) backwards analysis and b) Staged construction including time-dependent effects (form traveller not considered). 74 3-20 Tower and pier configurations. From left to right: Barton Creek Bridge, North Arm Bridge (LRT), Kiso and Ibi Bridges, Sunniberg Bridge, Odawara Blueway Bridge, Tsukuhara Bridge, Shin-Karato Bridge, Hozu Birdge, Miyakodagawa Bridge and Domovinski Bridge (LRT and road). See Table 2-1 for drawing sources. 76 3-21 Arrêt-Darré Viaduct, France (concept 1982-83): main span 100 m, span to depth ratio 27, cantilever construction with precast segments with voided webs (Mathivat 1988). 77 3-22 Barton Creek Bridge, United States (completed 1987): main span 103.6 m, span to depth ratio 27 at midspan, cantilever construction, with the fin poured progressively after completion of 3 segments (Gee 1991).