Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
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Shape Optimization for Prolonging Fatigue Life of a Structure

구조물의 피로수명 향상을 위한 형상 최적화

  • Published : 2002.08.01
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Abstract

Most of mechanical failures are caused by repeated loadings and therefore they are strongly related to fatigue. To avoid the failures caused by fatigue, determination of an optimal shape of a structure is one of the very important factors in the initial design stage. Shape optimization fer two types of specimens, which are very typical ones in opening mode in fracture mechanics, was accomplished by the linear elastic fracture mechanics and the growth-strain method in this study. Also shape optimization for a cantilever beam in mixed mode was carried out by the same techniques. The linear elastic fracture mechanics was used to estimate stress intensity factors and fatigue lives. And the growth-strain method was used to optimize the shape of the initial shape of the specimens. From the results of the shape optimization, it was found that shapes of two types of specimens and a cantilever beam optimized by the growth-strain method prolong their fatigue lives significantly. Therefore, it was verified that the growth-strain method is an appropriate technique for shape optimization of a structure having a crack.

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References

  1. Lee, O. S., Kim, D. J. and Ryu, H. H., 1999, 'Fatigue Crack Propagation and Fatigue Life Prediction Under the Mixed Mode Loading,' Transactions of the KSME, A, Vol. 23, No.9, pp. 1550-1558
  2. Ong, J. W., Jin, K. C., Lee, S. G. and Kim, J. B., 1989, 'Mixed-Mode Fatigue Crack Growth Behaviors in 5083-H115 Aluminum Alloy,' Transactions of the KSME, A, Vol. 13, No.3, pp. 461-471
  3. Sih, G. C., 1974, 'Strain-Energy-Density Factor Applied to Mixed Mode Crack Problems,' Int. J. of Fracture, Vol. 10, pp. 305-321 https://doi.org/10.1007/BF00035493
  4. Wong, A. K., 1987, 'On the Application of the Strain Energy Density Theory in Predicting Crack Initiation and Angle of Growth,' Eng. Fracture Mech., Vol. 27, pp. 157-170 https://doi.org/10.1016/0013-7944(87)90165-2
  5. Williams, J. G. and Ewing, P. D., 1972, 'Fracture under Complex Stress-The Angled Crack Problem,' Int. J. Fracture Mech., Vol. 8, pp. 441-445 https://doi.org/10.1007/BF00191106
  6. Baek, T. H., 1992, 'Photoelastic Analysis of Stress Field in the Neighborhood of a Mixed Mode Crack Tip,' Transactions of the KSME, A, Vol. 16, No. 11, pp. 2072-2081
  7. Song, S. H. and Lee, K. R., 1997, 'Short Crack Analysis by Fatigue Crack Opening Behavior,' Journal of KSPE, Vol. 14, No.4, pp. 136-144
  8. Gani, L. and Rajan, S. D., 1999, 'Use of Fracture Mechanics and Shape Optimization for Component Designs,' AIAA Journal, Vol. 37, No. 2, pp. 255-260 https://doi.org/10.2514/2.698
  9. Han, S. Y. and Bae, H. W., 1999, 'Shape Optimization for General Two-Dimensional Structures,' Transactions of the KSME, A, Vol. 23, No.9, pp. 1622-1627
  10. Shimoda, M., Sajura, T., Kondo, Y. and Azegami, H., 1993, 'Shape Optimization of Solid Structures Using the Growth Strain Method (Application to Chassis Components),' SAE 1992 Transactions, Vol. 101, Section6, pp. 1136-1145
  11. Anderson, T. L., 1995, Fracture Mechanics (Fundamentals and Applications), 2nd ed., CRC Press
  12. Barry, D. and Fehl Kevin Z. Truman, 1999, 'An Evaluation of Fracture Mechanics Quarter-Point Displacement Techniques Used for Computing Stress Intensity Factors,' Engineering Structures, Vol. 21, pp. 406-415 https://doi.org/10.1016/S0141-0296(97)00221-6
  13. Pang, H. L. J., 1993, 'Linear Elastic Fracture Mechanics Benchmarks: 2D Finite Element Test Cases,' Engineering Fracture Mechanics, Vol. 44, No.5, pp. 741-751 https://doi.org/10.1016/0013-7944(93)90203-5
  14. Kim, I. L., Johnston, L. W. and Choi, S. K., 1992, 'Comparison Between Various Displacement-Based Stress Intensity Factor Computation Techniques,' International Journal of Fracture, Vol. 58, pp. 193-210 https://doi.org/10.1007/BF00015615
  15. Hong, K. J., Kang, K. J., 1996, 'Method to Measure Kb KII and J-Integral for CTS Specimen Under Mixed Mode Loading,' Transactions of the KSME, A, Vol. 20, No. 11, pp. 3498~3506
  16. Tada, H., Paris, P. C. and Irwin, G. R., 1973, The Stress Analysis of Cracks Handbook, Del Research Corporation
  17. Dowling, N. E., 1999, Mechanical Behavior of Materials, Prentice-Hall, p. 506