SOCIEDAD CHILENA DE INGENIERIA HIDRÁULICA V SEMINARIO INTERNACIONAL DE INGENIERÍA Y OPERACIONES PORTUARIAS OCTUBRE 2008, CONCEPCIÓN, CHILE Influence of Marine Operations on Site Selection & Design of Marine Terminals Presented by: Capt. Stephen Gyi. Ex.C. stephen.gyi@ultmar.com
Introduction
Marine Terminal and Vessels The Relationship Between a Marine Terminal, Vessels, Ship/Shore Interface and Operations is Paramount to Effective, Cost Efficient and Safe Design Vessels in Confined Waters Visiting a MarineTerminal Ship / Shore Interface Marine Terminal, Including Berth(s) We tend to disregard the importance of these during the initial design
Marine Terminal Today most marine terminals are designed with more emphasis on the shore based terminal Insufficient marine data and studies are carried out to ensure accurate BoD, and the long term efficiency and safe operations of the Terminal Proper marine input at the beginning of a project has been proven to improve safety, design and construction schedule, together with substantial Capex and long term Opex cost savings
Presentation Objectives This presentation highlights some of the marine topics that should be considered at the start of a marine terminal project Whilst not going into detail, each section introduces a topic that can be further explored to get a better grasp of the subject Each topic covers a specialist area, and therefore specialist participation is desired if the conclusions are to reflect the most accurate marine inputs for any proposed terminal location
Milford Haven Why Marine Input?
Accidents Can Happen Alaska
Preliminary Evaluation of Potential Marine Terminal Sites, and the Types of Locations
The World A new marine terminal can be located anywhere in the world, and is exposed to similar marine elements and various levels of shipping. The severity of these determines the levels of risk, which can all be mitigated with knowledge, understanding, good planning and perceptive design
The Continent and Country Consider a new terminal for Chile, and the challenges of different locations along the coast.
Types of Marine Locations The following are a few types of marine berth locations, either green field or brown field sites: ~ Within sheltered port location, with exposed entrance ~ Within sheltered port location within a bay, with sheltered entrance ~ Semi-exposed berth location, with or without wave protection ~ Exposed berths, with or without wave protection
Local Information Input Some of the marine information beneficial to the design from the outset: ~ Topography and bathymetry (confined waters) ~ Confinements, and operations of others in the vicinity ~ Range of vessels to visit the berth(s) ~ Traffic studies and storage requirements for throughput ~ Wind Conditions, including local wind effects ~ Storms (TRS), squalls, lightening ~ Wave direction and spectral shape ~ Currents at various levels ~ Tidal ranges, surges, seiches and Tsunamis ~ Precipitation and visibility ~ Air and sea temperature profiles, and solar energy ~ Points to note for design Such important input should be analysed and provided by specialists in the designated areas
Provides Information For This provides the most accurate information for: Basis of Design (BoD) Various marine computer models Initial designs for pre-feed Design parameters for FEED, and detailed design Research navigation simulation to determine best alignment and location of berth(s), tugging, mooring and NavAid requirements Static and dynamic mooring analysis Determine maximum allowable MetOcean operating parameters Requirements for dredging (initial and maintenance) Marine aspects of the EIA, and maritime concession permitting Marine QRA Familiarisation simulation for the pilots and tug masters, including emergency scenarios
The Supply Chain
The Supply Chain This applies to all shipping, but we will take LNG as an example Weakest Links in the Chain
Selection of Berth Location from a Marine Perspective
Quintero Bay Showing Waves
Chart Showing Berth Location
LNG Jetty Location
Static and Dynamic Mooring Analysis
Berth Layout Any berth layout must be the optimum for the range of vessels in the BoD, and declared by the client
Static & Dynamic Mooring Analysis In accordance with OCIMF, and other industry standards
Dynamic Mooring Analysis
Downtime Estimates The client needs to stipulate their allowable down time requirements from the outset, which will mould the BoD
Marine Equipment
Fixed Shore Gangway The gangway can be lifted clear, or will automatically clear the vessel in the event of it moving away from the berth unexpectedly
Each hook is fitted with a load cell for tension monitoring, and individual local and remote hook release systems. The hooks can be activated remotely in the event of an emergency, when it is deemed safer for the vessel to leave the berth. Mooring Hooks
Berthing Parameters
Fenders (sheltered location) Dolphins and fenders are usually designed to take 20 t/m 2 loads, but some newer vessel hulls can only absorb 14 t/m 2 loads
Fenders (exposed locations) These fenders tend to be larger is size because the dynamic loadings on them can be greater than the berthing forces
Dynamic Movements of Vessels
All vessels have 6DoF Six Degrees of Freedom
Block Coefficient The block coefficient of displacement determines the Lines of the vessel, and its cargo carrying capacity
Vessel s Line Plan Lines Plan of a cargo vessel with average fineness Today the computerization of ship building integrates all plans and calculations within a suite of software, much the same as when designing a marine terminal
Rudder Forces It is important to understand how a rudder works to recognize how to control a vessel when it becomes ineffective in an emergency because of mechanical breakdown
Rudder Force Comparisons By comparing rudder angle against speed through the water (i.e. water flow) for any vessel, there is relatively little increase in rudder force for increased rudder angle at a given speed, but a relatively large increase in rudder force for a given rudder angle with increase in speed through the water
Statical and Dynamical Stability A curve of statical stability must show a vessel is safe to proceed to sea under any loaded condition, and maintain adequate stability throughout a voyage. Dynamical stability can be calculated from the statical stability curve
Beam Wind Effect For a longitudinal windage of 8000 m 2 For 10 kts = 17 Tonne For 20 kts = 50 Tonne For 30 kts = 145 Tonne
Beam Wave Effect For a vessel 300m PP: 1.0m = 36 Tonne 1.5m = 78 Tonne 2.0m = 135 Tonne
Beam Current Effect For an underwater area of 3000m, and Depth to Draught ratio of 1.1: 0.4 kts = 25 Tonne 0.7 kts = 70 Tonne 1.0 kt = 150 Tonne
Under Keel Clearance Effect The force required to move a vessel at a constant velocity over a flat bottom increases with reduction in UKC, for the same vessel in a constant current flow with the same draught
Squat Effect Tanker example: Bow sinkage Trim EK 20m water depth Speed 14 knots 300m length = 2.0m
Thruster Effect A vessel s thruster is reduced to about 50% effectiveness when its speed through the water is around 3 knots, and becomes of little or no use above a speed of 4 knots Tugs are therefore much more effective during escorting and manoeuvring than bow or stern thrusters
A Vessel s Inertia
Inertia and Mass Newton s First Law states Every body continues in its state of rest or uniform motion in a straight line, unless impressed forces act upon it Inertia: the resistance an object has to a change in its state of motion (i.e. its velocity or acceleration) All objects resist changes in their state of motion. All objects have this tendency - they have inertia. Some objects have more of a tendency to resist changes than others. The tendency of an object to resist changes in its state of motion varies with mass. Mass is that quantity which is solely dependent upon the inertia of an object. The more inertia which an object has, the more mass it has. A more massive object has a greater tendency to resist changes in its state of motion Likewise all vessels moving through water have inertia, and react in the same way as any other object
Kinetic Energy As a vessel is driven through water its engine does work, which is a product of force and the distance covered. The power of the engine is the work done over the time taken, and is expressed in HP or KW for a vessel Any moving object possesses kinetic energy as it can do work. KE = ½mv 2, where m is in kg and v is in m s -1 (and 1 m s -1 is about 2 knots) For every small increase in speed, a vessel s KE substantially increases. For a 100,000 Tonne displacement vessel: - at 4 knots the vessel s KE is 4 times greater at 400 KJ - at 8 knots the vessel s KE is 16 times greater at 1,600 KJ - at 12 knots the vessel s KE is 36 times greater at 3,600 KJ At full sea speed of 20 knots a 100,000 Tonne displacement vessel (e.g. a LNGC) has 10,000 KJ of kinetic energy, which is why vessels slow down to a manoeuvring speed of around 12 knots or less when entering confined waters
Escort and Harbour Tug Designs
Controlling Inertia Using tethered tugs is the best way to control inertia: ~ Tugs can be used in the Active (tethered) mode, or in a Passive mode (untethered) ~ The number of tugs required to fulfil any safe escort and manoeuvring operation should be based on the prevailing metocean conditions at the time, the type of vessel, the design and power of the tugs, and the expertise of the pilot and tug masters familiar with the type of vessel ~ Consideration should be given to the restrictions to manoeuvring, and the handling characteristics of the vessel and tugs when deciding how many tugs to use and how the tug forces need to be balanced throughout the escort and manoeuvring
Various Tug Thrust Vectors
Modern ASD Tugs
Tug Effectiveness Curves
Tugging Tugging requirements for a marine terminal are based on: ~ Best Industry practises, and Company standards ~ Maintaining total control of the vessel whilst manoeuvring in confined waters, including under emergency situations ~ Active escort and harbour assist requirements meeting the requirements of the Port Authorities and the Company ~ Total effective static bollard pull necessary for operating in the maximum allowable MetOcean parameters as determined by modelling and simulation. This is to keep downtime to an acceptable level in order to keep the supply chain and schedules intact, and protect the Port ~ Fire fighting (FiFI1) and rescue requirements
Tug Escort and Harbour Assist
Active Tug Escort Very effective means of steering a vessel when its rudder or main engine becomes unavailable
INDIRECT TOWING
POWERED INDIRECT
Performance Against Speed 75 50 Line Pull (Tonne) 25 Direct Powered Indirect Indirect 0 2 4 6 8 10 Speed (knots)
Active Tug Escort Configuration
Tug Turning Vessel Off Berth
Tug Harbour Assist
Marine Risks
Risks in Confined Waters Grounding of vessels under power is by far the largest risk in shallow water
Risk Reduction in Confined Waters The most effective way of mitigating the risk of vessels grounding under power is by using experienced pilots familiar with the type of vessel, and an adequate number of sufficiently powered tugs with highly trained tug masters
Navigation and Docking Aids
Traditional Navigation Aids
NDMO Block Diagram
Latest PPU Technology
PPU Laptop This provides the pilot with: accurate position and speeds Real-time metocean information accurate docking information ECDIS charts for navigation AIS data
Navigation Screen
Advanced Path Prediction Advanced Path Prediction
Approach and Docking
Approach and Docking The introduction of such modern navigation aids allows for reduction in the safety margins of a marine terminal design because a vessel s berthing will be much better controlled. Risk reduction, both safety and monetary, associated with this can be substantial. Moreover the terminal, and port as a whole, operates more safely and cost effectively. Therefore everyone benefits
Navigation Simulation for Research, and then Familiarization Training
Full Mission Bridge Simulator
Typical Bridge Layout
Quality of Digitization
Digitized Reduced Visibility
Simulator Definition
Simulator Definition
Simulation run plots
Fast Time Simulation
Fast Time Simulation
Conclusions Port Management Navigation Aids Active Escorting Operating Procedures Good Site Selection and Proper Design PORT SAFETY Security Cooperation of Everyone Marine QRA Pilots Tugs & Tug Masters Accurate Marine Information
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