ANNEX 1 SPECIAL REQUIREMENTS FOR PUSHER-BARGES

1. Application

(1) The requirements of this Annex apply to the barges which are barges connected to pusher that are operated

intended to be classed as pusher-barges by the pushing of pusher.

(2) For items not specified in this Annex, the requirements of Rules for Classification Steel Barges

and Guidance relating to Rules for Classification Steel Barges are to be applied.

(3) Alternative hull, connection construction and equipment will be accepted by the Society, pro- vided that the Society is satisfied that such hull, connection construction and equipment are

equivalent to or above those required in this requirements.

2. Definition

(1) Hard connection : Hard connection is a combination method where a barge and pusher is con- nected to behave as a one unit during a voyage without relative motion between the two.

(2) Soft connection : Soft connection is a combination method where a barge and pusher is con- nected to allow relative motion with one or more degree(s) of freedom during a voyage.

Pusher-barge connected by this method is to engage in coastal services.

(3) Length of connection Ãᾏ : Length of connection Ãᾏ is distance in meters along the load line which is from inside face of side plate or forward side of fore part structure to after side of rudder post or the centre of the rudder stock under the hard connection condition.

(4) If the connection is based on hydraulic operation, the mechanical locking devices are to be fit- ted to hold locking condition even if the hydraulic system is failed in locking condition.

(5) Hydraulic system and drawings relating to the connection are to be submitted.

(6) Operational procedure for connection system is to be provided onboard, and its copy submitted to the Society.

is to be

3. Longitudinal strength

(1) Calculation of longitudinal strength

(A) Longitudinal strength of pusher-barge with hard connection is calculated accordance

4 of the Rules using length of connection Ãᾏ.

(B) Longitudinal strength of pusher-barge with soft connection is calculated accordance

4 of the Rules using length of connection à .

(2) Still water bending moment and shear force

with Ch

with Ch

(A) Still water bending moment and shear force of hard connection are calculated for connected

unit of barge and pusher.

(B) Still water bending moment and shear force of soft connection are calculated for barge only.

(3) Loading manual

The requirements of Ch 4, 101. of Guidance are to be complied with according to length of

connection Ãᾏ

4. Calculation of scantlings

(1) Scantlings of pusher

Scantlings of pusher are to comply with the "Rules for the Classification of Steel Ship" using length of pusher only. In case of pusher-barge with hard connection, scantlings of the pusher's hull structure(deck, shell, frame, superstructures, deckhouses, etc.) which will be exposed to wave loading when the pusher is acting as part of the combined unit(pusher + barge) should be designed using Ãᾏ . In this case, the scantlings are to be not less than the scantlings complying with the pusher's length only.

(2) Scantlings of barges :

In calculating the scantlings of each connection barge and length of barge

(3) Position of forepeak bulkhead

member, length of connection Ãᾏ is to be used for hard

à for soft connection barge.

Forepeak bulkhead of barge is to be located between 0.05Ãᾏ and 0.08Ãᾏ. length of connection is less than 90 m, forepeak bulkhead may be located

However, when the

between 0.05Ãᾏ and

0.13Ãᾏ.

5. Equipment number and equipment

Equipment number and equipments are to comply with Ch 19 of the Rules using Ãᾏ.

6. Type of pusher-barges

Pusher-barges are classified into two types and are to comply with Table 1.

Table 1 Type and Application of Pusher-Barge

7. Connection structure of pusher-barge

(1) For the stress assessment of all strength direct calculation is to be carried out.

members related with connection of pusher and barge,

(A) Where deemed necessary by the Society, the wave hull girder loads and the forces

mitted through the connection are to be calculated from a direct calculation of the er- barge combination motion and acceleration in irregular waves, unless such data are able

from similar ships.

trans-

push-

avail-

(B) These loads are to be obtained as the most probable that the pusher-barge combination may

experience during its operating life for a probability level of ÌLŇ K. For this calculation, the wave statistics relevant to the area of navigation and weather condition are to be taken into account.

(C) When the difference between the pusher and the barge depths is considered to be not negli- gible by the Society, its effects are to be considered in evaluating the buoyancy force dis- tributions and the corresponding hull girder loads on the pusher structures immediately aft of the connection section, for the different wave encountering conditions.

(2) Permissible stresses in the connection are :

Normal stress : 225 ᾚÌ

NÕmm Ī

Shearing stress : 120 ᾚÌ

NÕmm Ī

ſſ← LǾKJ

ᾚÌ Ņ N ÜĪĮJŃ

ſſ← : yield stress of materials

(3) Data for direct reference.

calculation according to (1) and (2) are to be submitted to the Society for