Marine engineering

What is incorporated in the method of underwater pipeline crossings?                                                                                                 Tube immersed under water crossing method associated with the following basic steps:

(I) precast units along the tunnel (steel or concrete shell), a dry dock or shipyard

(Ii) the floats and the trailer with movable partitions for the site

(Iii) Immerse the specimens in a pre-excavated trench

(Iv) Combining a unit for a

(V) covers the complete tunnel

An immersed tunnel steel is sometimes adopted because of ease of manufacture and its relative ease. In addition, shorter construction time required compared to concrete immersed tubes
How does the direction of the approaching speed of ships affected by the pier?

One of the main effects of the angle of speeds approaching vessel is its effect on energy to be absorbed by the defense system. Consider more ships berth at the dock themselves at the same speed but with a different approach, although their kinetic energy is the same, the amount of energy absorbed by the wing is different. The amount of energy absorbed by the wing is:

approach speeds of ships

where W = absorbed by the fender

m = mass of the spacecraft

v = velocity of the ship

k = radius of gyration of the ship

r = distance between the center of gravity of the ship at the contact point for the wings

So, when the direction of approaching the speed of the ship is a normal wing (ie, phi = 90), the amount of energy absorbed is less than the vessel at a speed tangent to the beach.

What Is The Design Of Landings In The Pillars?                                                                    Landings has been designed as a resting place for passengers during docking and undocking of vessels. Typically, the data say landing near the top and the average low water to facilitate the embarkation and disembarkation of passengers (BS6349: Part 2: 1988). Therefore, the level of landing steps may be different from place to place because of different high and say the average level of low water in different places.

If Morison Equation And Diffraction Analysis Will Be Adopted In Determining The Strength Of The Waves On Stilts?                                                       The choice between the Morison equation and diffraction analysis in determining wave forces on the piles depends on the ratio between the diameters of the piles of wavelength. If the relationship between the diameter of the wavelength of the batteries is less than 0.2, the Morison equation is usually

recommended. The reason behind this is that the effect of viscosity and separation is considerably lower than that. On the contrary, if the relationship between the diameter of the mass of the wavelength greater than 0.2, the waves are scattered with a negligible impact of separation. Such as diffraction analysis was adopted to calculate the wave forces on piles

Hudson And The Formula For Van Der Meer Formula Is Commonly Used In The Design Of The Armor. Which Is The Best Choice?                         Hudson formula is often adopted in the preliminary design to obtain rough initial estimate of the size of stone. The formula is derived from the regular wave tests. But this formula does not take into account the following, as Van der Meer formula do: wave period, the level of damage, the permeability of the structure and duration of storm. In addition, the Hudson formula relates to the use of regular waves only.

Compared to the formula of Hudson, Van der Meer formula is more complicated and is derived from the results of a series of physical model tests. They include the examination of the period of the wave, the duration of storm, the level of damage defined and the permeability of the structure. The choice of the appropriate formula depends on the design objectives (ie preliminary design or detailed design).

What Are The Factors That Determine The Stability Of A Single Armored Unit?                                      There are three main factors governing the stability of an armored unit, namely the severity, the treatment of inter-and algae clip. Obviously, it is beyond doubt that the ability of the armored unit to stay in place must be closely related to the gravitational force. Moreover, the geometry of the armored unit affecting its stability. For example, the difference in the ability to intertangle reluctance to get out of the wave varies. Moreover, the forces pushing gravity also affects the stability of the armored unit that depends on friction forces in all directions.
If A Small Boat To Take Into Account The Design Of Wings?                                                                The smaller ship should also be taken into account when designing a system fender. Vertically and the fender system, type and size of all vessels must be considered taking into account the influence of tides in the region. In fact, plans to visit a fender system, engineers must take into account the height and depth as well as smaller and larger vessels in a point of contact is a fender. It is not uncommon for the design of a fender system considers only the largest of the ships dock and pier, which should be avoided, because it does not necessarily work for small boats in the dock of the shipyard.
                                                              

                                                                                                                                                                    If The Wings Rigid Or Flexible To Be Designed To Dock At Piers?                                                        The elasticity of the wings is related to the ability to release the energy stored in the docking of ships. But it has no effect on the reaction force and the deflection of the fender system. The amount of energy that can absorb a wing depends on the deflection curve of reaction and is represented by the area under the curve. The higher is the reaction force would be the largest amount of energy absorbed by the fender, provided that the hull strength is sufficient to withstand the force without permanent deformation. While rigid and flexible wings can have the same deflection under the maximum reaction force acting on the boat dock, the amount of energy absorbed by the rigid wings are much higher than in soft wings. Therefore, rigid wings used for docking.

On the other hand, in mooring operations where vessels are constantly subjected to wave action, it is desirable to keep the pull of the rope to a low value. In this regard, it recommends the use of flaps  Water Can Help Dispel Some Of The Energy Coupling?                                                                                                          Depending on the composition of the pier, the water could help to dissipate the energy of the pier. For example, the closed door, which is a solid wall going straight to the bottom of the sea, the quay wall to repel any water that moves the ship and creates a cushion effect, which dissipates the energy of the pier ( 10-20%). In contrast, an open yard, with piles everywhere and the water can flow through the bottom of the platform, not cushion the effect of the water.

Similarly, the most important is the draft of vessels, less water can escape trapped under the ship to the dampening effect of water can be enhanced to dissipate some energy coupling.