Ship berthing energy calculation

Ship berthing energy calculation

The berthing energy and rubber fender reaction load are the most important parts in choosing the type of the rubber fender. As a typical example of Ghana some new terminal expansion project, by analyzing and calculating the absorption distribution of fender system, we changed the single energy-absorbing fender mode to multiple energy-absorbing fenders which is allowed by the standards of China and British. When the ship berthing, we used the different berthing points to analyze the adverse berthing conditions, by using the ship bow radius, fender energy absorption capacity and the corresponding deformation as the analysis of factors to determine the different points of impact fenders involved in energy absorption ( The number of different fenders is also called different berthing conditions) . According to the different berthing conditions, we analyzed and calculated the energy absorption and deformation of the fender group to get the optimal rubber fender model that meets the requirements of energy absorption and wharf structure protection, so as to realize the optimal design of the fender.

Ship berthing impact on the fender The energy expression is：

Where: E is the impact energy, kJ;

MD is the ship's displacement, t;

VB is the berthing speed of the ship when berthing normally, m/s, which is determined by checking the table according to whether the berthing quay is covered or not, the difficulty of berthing conditions, and the ship's displacement;

CS is the flexibility coefficient, 0.9~1.0, 0.9 is taken when the fender is continuously arranged, 1.0 in other cases;

CC is the berth shape coefficient, 0.8~1.0 0.8~1.0, open high pile quay takes 1.0, solid quay takes 0.8~1.0, usually takes 1.0;

CM is the additional water influence coefficient of the ship;

CE is the eccentricity coefficient.

1) Ship additional water impact factor is calculated as follows.

DV is the draught of the ship corresponding to the calculated loading degree, m; B is the ship type width.

2) The eccentricity coefficient is calculated as follows

The ship's radius of gyration K is calculated as follows

Cb is the square factor; L is the length between the ship's vertical lines, m; R is the distance from the ship's center of mass to the berthing point, m; γ is the acute angle between the berthing direction and R, (°)