## Pontoons

• dynamically supported craft

The main design criteria of the code are:

• General intact stability criteria for all ships:

1. e030° > 0.055 mrad; e030° is the area under the static stability curve to 30°

e0,40° > 0.09 m rad; corresponding area up to 40°

e30,40° > 0.03 m rad; corresponding area between 30° and 40°.

If the angle of flooding 0/ is less than 40°, 0/ instead of 40° is to be used in the above rules.

2. h30° > 0.20 m; h30° is the righting lever at 30° heel.

3. The maximum righting lever must be at an angle 0 > 25°.

4. The initial metacentric height GMo > 0.15 m.

• In addition, IMO requires for passenger ships:

1. The heel angle on account of crowding of passengers to one side should not exceed 10°. A standard weight of 75 kg per passenger and four passengers/m2 are assumed.

2. The heel angle on account of turning should not exceed 10°. The heeling moment is y2 /_ f

Severe wind and rolling criterion (weather criterion):

The weather criterion is intended to reflect the ability of the ship to withstand the combined effects of beam wind and rolling (Fig. A.4). The weather criterion requires that area b > a. The angles in Fig. A.4 are defined as follows:

00 angle of heel under action of steady wind; 16° or 80% of the angle of deck immersion, whichever is less, are suggested as maximum.

01 angle of roll windward due to wave action

0/ is the heel angle at which openings in the hull, superstructures or deckhouses, which cannot be closed weathertight, immerse. 0c angle of second intercept between wind heeling lever lw2 and righting arm curve. The wind heeling levers are constant at all heel angles:

A is the projected lateral area of the portion of the ship and deck cargo above the waterline in [m2].

Z is the vertical distance from the centre of A to the centre of the underwater lateral area or approximately to a point at T/2 in [m]. A is the displacement in [t].

The angle 01 [deg.] is calculated as

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