Section 1 Longitudinal strength

101. Section Modulus of Transverse Section

The section modulus of the hull for midship part is not to be less ing formula:

than obtained from the follow-

Ě Ņ ǼÃ ĪÆE NǼ ᾎÑ LǾKŃ NcmĮ Ń

where,

Ǽ : Coefficient obtained from the following formula. In no less than 44.

case, however, is it to be

0.4 Ã + 36

ÆE : Horizontal distance between the outside of side shell maximum load line (m ).

laminates at the designed

Ǽᾎ : Volume of displacement at the designed maximum load line divided by ÃÆE ᾘ.

102. Moment of Inertia of Transverse Section

The moment of inertia of the transverse section for 0.4 Ã of midship part is not to be less than obtained from the following formula :

Ā Ņ ĨǾĪĚÃ NcmĨ Ń

where,

Ě : Section modulus of the transverse section specified in 101. (cmĮ)

Where, however,

ÃÕÁ

for FRP ships of single bottom is less than 12.0, the calculation of the mo-

ment of inertia may be dispensed with.

103. Calculation of Section Modulus of transverse Section 【See Guidance】

The calculation of section modulus of the transverse section is to be in a accordance with the re- quirement in the following :

1. Longitudinal members below the strength deck which are considered as continuous for 0.5 Ã amid- ships are to be included in the calculation. Longitudinal members above the strength deck which are considered effective to the longitudinal strength of the ship may be included in the calculation.

2. The section modulus at the strength deck is the moment of inertia about the horizontal neutral axis

of the transverse section divided by the vertical distance from the neutral

strength deck beam at side, or to the top of the longitudinal members above case where such members are included in the calculation in accordance with

The section modulus at the bottom is the above-mentioned moment of inertia

axis to the top of

the strength deck in the provisions in 1.

divided by the verti-

cal distance from the neutral axis to the base point of Á, or to the bottom of keel in case where the keel is of hat-type construction.

3. The sectional area of timbers or structural plywoods multiplied the ratio of the modulus of tensile elasticity of the relevant material to that of the FRP is to be included in the calculation.

4. Where cores of sandwich laminates or cores for moulding are included in the longitudinal strength,

the sectional area multiplied by the ratio of the modulus of tensile elasticity of the relevant core to that of the FRP is to be included in the calculation. Where a joint of the core exists for 0.5 Ã

amidships, sufficient data with respect to the longitudinal strength and joints are

the Society for approval.

to be submitted to

104. Continuity of Strength

Longitudinal strength.

strength members are to be of such a construction as to maintain good continuity of