甲板積木材運搬船のSOLAS II-1章による損傷時復原性計算を行うにあたり、従来は、甲板上に積み付けられた木材の浮力を考慮出来ませんでしたが、木材の浮力を考慮するべきとしてIACSの統一解釈UI SC 161が、2000年4月25日にCouncilで採択され、2001年1月1日から実施されることとなりました。

但し、損傷時復原性計算では、浮力を考慮できる範囲は、それぞれ船首尾方向、幅方向で以下の通りとなります。( 図1参照願います。)


船首尾方向

実際の甲板積み付け高さに拘わらず標準船楼高さ一層分の甲板積み木材貨物を浮力として考慮するものとします。但し、損傷時復原性計算において船首尾方向の損傷範囲直上の木材貨物については、浮力が消失されるものとします。


幅方向

計算上の幅方向の損傷範囲にかかわらず、船首尾方向の損傷範囲の直上の木材貨物の浮力は、船の全幅に亙って浮力が消失されるものとします。

これにより、木材を甲板上に積む場合は、許容G0M曲線を木材満載喫水線を基に別途設定できることになり従来に比べ積載許容範囲が広がることとなります。

詳細については、添付のUI SC 161（英文、和文仮訳）を参照願います。

お問い合わせ:船体部

Tel. 03-5226-2018

Fax. 03-5226-2019

以上

添付：1. IACS UI SC 161（英文、和文仮訳）

2. IMO Resolution A.715 (17)第3章抜粋（英文、和文仮訳）

　

　

　

添付１．

IACS UI SC 161 (adopted on 25 April 2000 at Council)

Timber deck cargo in the context of damage stability requirements

(Chapter II-1, Regulation 25-8.1)

SOLAS Regulation II-1/ 25-8.1 reads:

Stability information

1 The master of the ship shall be supplied with such reliable information as is necessary to enable him by rapid and simple means to obtain accurate guidance as to the stability of the ship under varying conditions of service. The information shall include:

.1) a curve of minimum operational metacentric height (GM)versus draught which assures compliance with the relevant intact stability requirements and the requirements of regulations 25-1 to 25-6,alternatively a corresponding curve of the maximum allowable vertical centre of gravity (KG)versus draught, or with the equivalents of either of these curves;

.2) instructions concerning the operation of cross-flooding arrangements; and .3 all other data and aids which might be necessary to maintain stability after damage.

3) all other data and aids which might be necessary to maintain stability after damage.

Scope

The provisions given hereunder apply to ships that are subject to SOLAS, Chapter II-1, Part B-1 subdivision and damage stability calculations and engaged in carrying timber deck cargoes. The buoyancy of the timber deck cargo can optionally be taken into account in the damage stability calculations, subject to the provisions that have been set forth in this document.

They shall comply with the requirements of the “CODE OF SAFE PRACTICE FOR SHIPS CARRYING TIMBER DECK CARGOES,1991”, and Ships that are provided with and make use of their timber load line shall also comply with the requirements of regulations 41 to 45 of the “LOAD LINE CONVENTION,1966”.

Definitions

The following definitions apply for the purposes of this interpretation:

timber means sawn wood or lumber, cants, logs, poles, pulpwood and all other types of timber in loose or packaged forms. The term does not include wood pulp or similar cargo;

timber deck cargo means a cargo of timber carried on an uncovered part of a freeboard or superstructure deck. The term does not include wood pulp or similar cargo;

timber load line means a special load line assigned to ships complying with certain conditions related to their construction set out in the “LOAD LINE CONVENTION 1966” and used when the cargo complies with the stowage and securing conditions of the “CODE OF SAFE PRACTICE FOR SHIPS CARRYING TIMBER DECK CARGOES, 1991 (Resolution A.715(17))”;

deepest timber subdivision load line is the subdivision load line which corresponds to the timber summer draught to be assigned to the ship;

respective partial load line is the light ship draught plus 60%of the difference between the lig