Technical guide - Watercourses and bridges
The guide is intended for construction managers and owners, and forengineering structure designers; its purpose is to assist with thedesigning of water crossing structures and their appurtenant structures,such as access embankments. It aims to assist the understanding ofwatercourses and their hydrosystems, to present all of the sections onwhich the interference between the structure and the naturalenvironment is to be taken into consideration, with possiblereciprocity of the impacts.
The guide is intended for construction managers and owners, and forengineering structure designers; its purpose is to assist with thedesigning of water crossing structures and their appurtenant structures,such as access embankments. It aims to assist the understanding ofwatercourses and their hydrosystems, to present all of the sections onwhich the interference between the structure and the naturalenvironment is to be taken into consideration, with possiblereciprocity of the impacts.
Contents
Introduction .............................................................................................................. 7
Chapter 1 Generalities .............................................................................................. 9
1 - Generalities ................................................................................................................10
1.1 - Fundamental concepts regarding watercourses ......................................................................................................... 10
1.2 - Effect of bridges on the watercourses ......................................................................................................................... 12
1.3 - Effect of watercourse developments on the bridges .................................................................................................... 14
1.4 - Specific cases of navigable watercourses ................................................................................................................... 14
1.5 - Approach for conducting a hydraulics study .............................................................................................................. 15
Chapter 2 Hydraulics and bridges............................................................................ 17
2 - Hydraulics and bridges ................................................................................................. 18
2.1 - Hydrology concepts .................................................................................................................................................... 18
2.2 - Hydraulics concepts.................................................................................................................................................... 25
2.3 - Effects of bridges on liquid flows................................................................................................................................ 36
2.4 - Hydraulic risks incurred by the structures ................................................................................................................. 45
Chapter 3 Morphodynamics and bridges .................................................................. 51
3 - Morphodynamics and bridges......................................................................................... 52
3.1 - Morphodynamic concepts ........................................................................................................................................... 52
3.2 - Effects of bridges on the morphodynamics ................................................................................................................. 65
3.3 - Protection of structures against erosion ..................................................................................................................... 76
Chapter 4 Aquatic ecosystems and bridges.............................................................. 83
4 - Aquatic ecosystems and bridges ..................................................................................... 84
4.1 - General hydroecological concepts.............................................................................................................................. 84
4.2 - Disturbances created by bridges to aquatic ecosystems ............................................................................................. 91
Chapter 5 Navigation of inland waterways and bridges............................................103
5 - Navigation of inland waterways and bridges...................................................................104
5.1 - Concepts regarding navigation................................................................................................................................. 105
5.2 - Effect of the bridge on navigation............................................................................................................................. 113
5.3 - Effect of the navigation on the design of bridges ...................................................................................................... 114
5.4 - Signaling ................................................................................................................................................................... 119
5.5 - Examples................................................................................................................................................................... 121
Chapter 6 Taking the watercourse and the operation project into account ...............123
6 - Taking the watercourse and the operation project into account.........................................124
6.1 - Regulations and recommendations for taking the watercourse into account in the study of an engineering structure.......................................................................................................................................................................................... 124
6.2 - Methodology of the hydrological study..................................................................................................................... 134
6.3 - Preliminary engineering structure road project study (phase 1).............................................................................. 138
6.4 - Preliminary engineering structure project (phase 2)................................................................................................ 140
6.5 - Detailed project (phase 3) ........................................................................................................................................ 140
6.6 - Necessary data for a hydraulics study ...................................................................................................................... 141
6.7 - Work site ................................................................................................................................................................... 146
6.8 - Operation .................................................................................................................................................................. 149
6.9 - Participants............................................................................................................................................................... 151
Appendices ............................................................................................................153
Appendix 3-1: case study - Protecting a bridge against the risks of scouring and bypassing - The Logone river in Moundou..................................................................................................154
Appendix 3-2: Details for dimensioning riprap protections ...................................................158
Appendix 3-3: transversal protections - groins ....................................................................167
Appendix 3-4: estimation of the scouring risks at the bottom of the bridge supports (via the H.N.C. Breusers and Al. formula) .................................................................................................173
Appendix 3-5: RN 94 - Embrun diversion project (05) - Crossing structure for the Durance river - Morphodynamic study (2000-2005).....................................................................................177
Appendix 5-1: calculation of the protections due to propeller jets..........................................181
Appendix 5-2: design notes for the temporary support protections of the Richemond viaduct .....184
Glossary ................................................................................................................201
Bibliography ..........................................................................................................203
