Bed bank and shore protection

Faculty of Coastal Engineering BED, BANK & SHORE PROTECTION Lecturer: Pham Thu Huong Chapter INTRODUCTION (3 class hours) CONTENT General of Viet Nam coast The impacts cause the damages on coastal line Protect or not protect ? Coastal protection structures Working conditions and requirement with coastal structures How to look at protections ? How to deal with protections ? Schedule 45B (15Jan – 18May) ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ 15 Jan: Chapter 22 Jan: Chapter 29 Jan: Chapter 05 Feb: Chapter (cont.) 12 Feb: Tet holiday 19 Feb: Tet holiday 26 Feb: Chapter 05 Mar: Chapter (cont.) 12 Mar: Chapter ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ ¾ 19 Mar: Chapter (cont.) 26 Mar: Chapter 02 Apr: Chapter (cont.) 09 Apr: Assignment 16 Apr: Chapter 23 Apr: Chapter (cont.) 30 Apr: ??? 07 May: experiment 14 May: Summary General of Vietnamese Coast Islands in Ha Long as breakwaters Dong Chau beach (Thai Binh) Beach at Tien Giang river mouth (Go Cong) Sandy beach at Quang Binh Rocky beach at Hai Van mountain pass The impacts cause the damages on coastal line • Natural impacts: - Winds, typhoons ⇒ bring sand land ward or sea ward - Tides, salty water ⇒ erosion, rusted steel structures - Currents ⇒ erosion, creation - Waves ⇒ erosion, instability of coastal lines, damaging structures which protect bed, bank and shore - Chemical impacts ⇒ structures are corroded - Impacts of organisms Influence of pressure gradient on velocity profile Uniform accelerated Decelerated Turbulence in windtunnel contraction The total amount of turbulent kinetic energy, k, remains approximately constant Due to the increased velocity in the contraction, the relative turbulence, r, using the local mean velocity decreases 2.4 Free flow 50 100 Z Flow, velocities and turbulence in mixing layer Flow and velocities in jets Plane jets : um = 3.5 u0 x B Circular jets : um = 6.3 u0 x D b = 0.1 x b = 0.1 x u = um e ⎛ z⎞ ⎞ ⎛ ⎜ − 0.693 ⎜ ⎟ ⎟ ⎜ ⎝ b ⎠ ⎟⎠ ⎝ u = um e ⎛ ⎛R⎞ ⎞ ⎜ − 0.693 ⎜ ⎟ ⎟ ⎜ ⎝ b ⎠ ⎟⎠ ⎝ Turbulent fluctuations in circular jet instability of an axisymmetric jet effect of strong pressure gradients 2.5 Combination of wall flow and Free flow Flow separation around blunt and round body Vertical constriction and expansion (sill) Vertical expansion (backward-facing step) Horizontal expansion Horizontal constriction and expansion (groyne) Detached bodies 2.6 Load Reduction The end Chapter ... purposes How to look at protections? When and Where ? Building codes in eroding coastal line Hue Examples of protection How to deal with protections? Cause and effect Designed protections North coast... Engineering BED, BANK & SHORE PROTECTION Lecturer: PhamThu Huong Chapter Flow - Loads (3 class hours) Content 2.1 Introduction 2.2 Turbulence 2.3 Wall flow 2.4 Free flow 2.5 Combination of wall flow and. .. artificial dredging and creating, dams, culverts,… - Non-construction: sand nourishments, mangrove forests, laws, policies, institutions, organization methods and managements; propaganda, education,