Section 2 Deck structure

2.1.1 Where a machinery space is situated aft, the deck plating thickness is to be as required in Pt 3, Ch 5, 2.6 Deck plating. The corners of deck openings are to be of suitable shape and design to minimize stress concentrations.

2.1.2 Where a machinery space is situated amidships and large openings are provided in the strength deck, the thickness of the deck plating abreast of the openings may require to be increased in thickness above that required in the relevant ship type Chapter in Pt 4 Ship Structures (Ship Types), in order to maintain the strength of the hull girder.

2.2.1 The plating of lower decks and flats is to comply with the requirements of Pt 3, Ch 5, 2.6 Deck plating or the relevant ship type Chapter in Pt 4 Ship Structures (Ship Types). The thickness of platforms on which auxiliary engines are placed, is to be increased locally by 1 mm.

2.3.1 The section modulus of main deck beams and longitudinals in way of machinery spaces is to be 20 per cent greater than that required by Pt 3, Ch 5, 5.2 Deck stiffening or in the relevant ship type Chapter in Pt 4 Ship Structures (Ship Types), but for decks on which auxiliary engines are placed a further increase in way of 20 per cent is required, see also Pt 3, Ch 6, 5.3 Seats for auxiliary machinery 5.3.1.

2.4.1 In addition to the longitudinal girders and transverses, fitted to support the deck structure, deep beams are to be fitted at the fore and aft end of engine casings. Longitudinal girders may require to be fitted in line with the sides of casings. The depth of these deep beams and girders is to be at least twice the depth of the deck beams or longitudinals.