Section 4 Hull Girder Strength

401. Application

The hull girder strength of craft, constructed in aluminium alloy, is to be in accordance with Ch 3, Sec 4. The material factor is to be in accordance with the Guidance relating to the Rules. But others than the Guidance are to be as following formula; 【See Guidance】

: yield stress (N mm , proof load with 0.2 % permanent deformation) is not to be taken

402. Additional requirements

1. Where the forebody parts are transversely framed, the axial force, defined in Ch 2, 401. Par 6, is to be checked the following formula.

∆ kN

: as defined in Ch 2, 401. Par 6.

The distribution of stresses will depend on instantaneous forward immersion and on loca- tion of cargo.

2. Bottom structure in way of thrust bearings may need a check for the increased thrust when craft is retarted by a crest in front.

3. Allowable axial stress and associated shear stresses are to be related to the stresses already existing in the region.