DEFORMATION MEASUREMENTS ON AN UNDERWATER STRUCTURE RELATING TO BUCKLING

A structure suitable for underwater storage of liquids or a one atmosphere accommodation/operations chamber is described. The structure is an axisymmetric thin shell of revolution of optimum form in relation to the design hydrostatic head. The buckling tendencies of this type of thin membrane structure under external load were examined and details are given of the reaction of the shell to axisymmetric pressure and concentrated loadings as well as to symmetric point loads. the responses were based on electric resistance strain gauge measurements and displacement monitoring at various points on the inner and outer surfaces of the shell during incremental loading. Southwell type plots are employed to interpret the experimental data in terms of critical buckling loads. These nondestructive type experimental predictions are compared with theoretical values established using the finite element method with both axisymmetric shell of revolution and semi-loof thin shell elements. Good comparisons between experimental and numerical predictions are demonstrated. The shapes of the Southwell plots in relation to the measurement localities is discussed and also the validity of the approach. the general nature of buckling modes under the various loading forms is assessed. Zones sensitive to buckling are identified and the implications for the design of such structures outlined.

• Supplemental Notes:
  • Royal Aeronautical Soc., Stress Determination and Strain Measurement in Aeronautics, Naval Arch. & Offshore Engng., Conference, held Guildford, UK 7-8 Sept. 1988, p.11.1 [16 p., 17 ref., 13 fig.]
• Authors:
  • Royles, R
  • El-Deeb, K M
  • Llambias, J M
• Publication Date: 1988

Language

• English

Subject/Index Terms

• TRT Terms: Buckling; Strain measurement; Underwater structures
• Subject Areas: Bridges and other structures; Marine Transportation;

Filing Info

• Accession Number: 00697216
• Record Type: Publication
• Source Agency: British Maritime Technology
• Files: TRIS
• Created Date: Aug 14 1995 12:00AM