Page 220 - Marine Structural Design

196 Part II Ultimate Strength

generalization makes it possible to effectively conduct analysis of plated structures and shell
structures (see Ueda and Yao, 1982). It is also possible to include the effect of strain hardening
in the formulation, see Ueda and Fujikubo (1986). However, geometrical nonlinearity is not a
subject discussed in the plastic node methods.
The Idealized Structural Unit Methods (Ueda and Rashed, 1984) make use of the Plastic Node
Methods to deal with the plasticity, and utilize empirical formulae (such as those in design
codes) for ultimate strength analysis of individual components. In this Chapter, however, an
attempt has been made to predict the ultimate strength of the components using simplified
inelastic analysis instead of empirical formulae. The advantage of using the simplified
inelastic analysis is its ability to account for more complex imperfection and boundary
conditions that are not covered in the empirical formulae. However, the disadvantage is its
demand for computing effort and its complexity that may lead to loss of convergence in a
complex engineering analysis.

9.7 References
1. AISC (1978), “Specification for the Design, Fabrication and Erection of Structural
Steel for Buildings, with Commentary”, American Institute of Steel Construction.
2. API RP 2A, (2001), “Recommended Practice for Planning, Designing and
Constructing Fixed Offshore Platforms - Working Stress Design (WSD), or - Load
Resistance Factored Design (LRFD)”, (latest revision), American Petroleum Institute.
3. Bai, Y. (1989), “Load Carrying Capacity of Tubular Members in Offshore Structures”,
Ph.D. Thesis, Hiroshima University, Jan. 1989.
4. Batterman, C.S. (1 963, ‘Tlastic Buckling of Axially Compressed Cylindrical Shells”,
AIAA J., V01.3 (1965), pp.316-325.
5. Bouwkamp, J.G. (1979, “Buckling and Post-Suckling Strength of Circular Tubular
Section”, OTC, No-2204, PP.583-592.
6. Chen, W.F. and Han, D.J. (1985),”Tubular Members in offshore Structures”, Pitman
Publishing Ltd, (1985).
7. Det norske Veritas (1981), Rules for Classification of Mobile Offshore Units (1981).
8. Gerard, G. (1 962), “Introduction to Structural Stability Theory”, McGraw-Hill
International Book Company, New York.
9. Rashed, S.M.H (1980), “Behaviour to Ultimate Strength of Tubular Offshore
Structures by the Idealized Structural Unit Method”, Report SK/R 51, Division of
Marine Structure, Norwegian Institute of Technology, Trondheim, Norway.
10. Reddy, B.D. (1979), “An Experimental Study of the Plastic Buckling of Circular
Cylinder in Pure Bending”, Int. J. Solid and Structures, Vol. 15, PP. 669-683.
11. Smith, C.S., Somerville, W.L. and Swan, J.W. (1979), “Buckling Strength and
Post-Collapse Behaviour of Tubular Bracing Members Including Damage Effects”,
BOSS, PP.303-325.
12. Toi, Y. and Kawai, T. (1983), “Discrete Limit Analysis of Thin-Walled Structures
(Part 5) - Non-axisymmetric Plastic Buckling Mode of Axially Compressed Circular
Shells”, J. Society of Naval Arch. of Japan, Na. 154, pp.337-247 (in Japanese).