A PARAMETRIC STUDY OF THE STRESS DISTRIBUTION IN A FOUR-CELLED BOX BEAM MODEL OF THE ASR-21 CLASS CATAMARAN CROSS-STRUCTURE

The objectives of this thesis are: (a) to attempt to analyze the stress distribution in the cross structure of the ASR-21 Class Catamaran by finite element analysis; (b) to develop a set of plating effectiveness curves for a doubly symmetrical model of the catamaran cross structure. This study is three dimensional in nature. Various geometric parameters are varied for the model to analyze what effect they produce on the resultant stresses in the cross structure. The catamaran cross structure and models are assumed to be cut at the inboard side of each hull and removed for proper loading. The three loadings used are symmetric bending moment, antisymmetric bending moment and shear, and torsional moment. The effectiveness of the various element sections of the actual ASR-21 catamaran cross structures is generally higher than that predicted by the model effectiveness curves. The effective breadth used for the design of the ASR-21 Class catamaran cross structures is very conservative when compared to the actual effective breadths determined in the thesis. Linearity in the stress distribution response to various loading conditions was observed. An effort should be made to study additional structural cross sections planned for use in future catamaran cross structures, and to examine the plating effectiveness at the higher L/B ratios proposed for them. A satisfactory analytical solution of the cross structure using the stress function should be conducted.

• Corporate Authors:

  Massachusetts Institute of Technology

  Department of Ocean Engineering, 77 Massachusetts Avenue
  Cambridge, MA  United States  02139
• Authors:
  • Penton, P H
• Publication Date: 1972-6

Subject/Index Terms

• TRT Terms: Beams; Bending moments; Catamarans; Finite element method; Structural analysis
• Old TRIS Terms: Beams (Structural)
• Subject Areas: Marine Transportation; Materials; Vehicles and Equipment;

Filing Info

• Accession Number: 00044167
• Record Type: Publication
• Source Agency: Massachusetts Institute of Technology
• Files: TRIS
• Created Date: May 11 1973 12:00AM