GRILLAGE BEAMS CALCULATIONS IN SHIP STRUCTURES

CALCOLD DEI GRIGLIATI NELLE STRUTTURE NAVALI

A method is presented for the calculation of double bottom local stresses of bulk-carriers, based on the study of a continuous grillage formed by the bottom grillages of the different holds (spans). By means of some hypotheses on the degree of fixation of the floors, which lead to a formula and the difinition of the grillage constants characteristic of each simple grillage, the solution is reached for the continuous beam formed by the central girder of the ship and the knowledge is therefore obtained of the bending stresses and constraint conditions on the transverse sides of each span. Having so obtained the boundary conditions of all the spans by means of other constants, it is possible to calculate the stresses on the central girder and central floor (central cross) of each hold which are generally the most stressed beams, or by means of an electronic computer, the stresses on every beam. The formulae of bending moments on the central girder in way of transverse bulkheads are reported and some calculation forms are shown. Parameters are tabulated for the calculation of the constants with which the shear and bending stresses on the beams of the central cross of every double bottom are determined. The calculation procedure of the bottom stresses in bulk-carriers here proposed can be applied, with proper adaptations, to other similar structures as bottom structures of other types of ships, ship's sides, decks, and so on. In Italian

• Corporate Authors:

  Registro Italiano Navale

  20 Via Vente Settembre
  Genoa,   Italy 
• Authors:
  • DeMaria, S
  • Squassafichi, N
• Publication Date: 1967-6

Media Info

• Features: Appendices; Tables;
• Pagination: 210 p.
• Serial:
  • Issue Number: 18

Subject/Index Terms

• TRT Terms: Beams; Bending moments; Bulk carriers; Hulls; Structural analysis; Vehicle design
• Uncontrolled Terms: Ship design
• Old TRIS Terms: Grillage beams; Hull bending moments
• Subject Areas: Design; Marine Transportation; Materials;

Filing Info

• Accession Number: 00019322
• Record Type: Publication
• Source Agency: Registro Italiano Navale
• Report/Paper Numbers: Tech Rpt
• Files: TRIS
• Created Date: Nov 8 1971 12:00AM