# 복합재료 라미네이트 경량화 자전거 프레임의 강도 설계

• 이진아 (연세대학교 기계공학부) ;
• 홍형택 (연세대학교 기계공학부) ;
• 전흥재 (연세대학교 기계공학부)
• Accepted : 2012.12.10
• Published : 2013.02.04
• 80 17

#### Abstract

Strength design for a lightweight bicycle frame made of carbon/epoxy composite laminates was studied using Tsai-Wu's failure criterion. For the design of bicycle frames, reducing the weight of the frame is of great importance. Furthermore, the frame should satisfy the required strength under specific loading cases. In accordance with the European EN 14764 standard for bicycle frames, three loading cases-pedaling, vertical, and level loadings-were investigated in this study. Because of the anisotropic characteristics of composite materials, it is important to decide the appropriate stacking sequence and the number of layers to be used in the composite bicycle frame. From finite element analysis results, the most suitable stacking sequence of the fiber orientation and the number of layers were determined. The stacking sequences of $[0]_{8n}$, $[90]_{8n}$, $[0/90]_{2ns}$, $[{\pm}45]_{2ns}$, $[0/{\pm}45/90]_{ns}$ (n = 1, 2, 3, 4) were used in the analysis. The results indicated that the $[0/{\pm}45/90]_{3s}$ lay-up model was suitable for a composite bicycle frame. Furthermore, the weakest point and layer were investigated.

#### Keywords

Composite Laminate Bicycle Frame;Finite Element Analysis;Stacking Sequence;Tsai-Wu Failure Criterion

#### Acknowledgement

Supported by : 국민체육진흥공단

#### References

1. Kwon, K. B. and Jung, S. K., 2007, Report of the Development Strategy for Bicycle Industry, Korea Institute of Sport Science.
2. Peterson, L. A. and Londry, K. J., 1986, "Finite- Element Structural Analysis: A New Tool for Bicycle Frame Design," Bike Tech, Vol. 5, pp. 1-9.
3. Lessard, L. B. and Nemes, J. A., 1995, "Utilization of FEA in the Design of Composite Bicycle Frames," Composites, Vol. 26, No. 1, pp.72-74. https://doi.org/10.1016/0010-4361(94)P3633-C
4. Liao, C. J., 2007, "Stiffness Analysis of Carbon Fiber Bicycle Frame," Master thesis of Department of Mechanical and Computer Aided Engineering, Feng Chia University.
5. CEN, 2005, "EN 14764:2005 City and Trekking Bicycles - Safety Requirements and Test Methods," CEN.
6. Daniel, I. M. and Ishai O., 1994, Engineering Mechanics of Composite Materials, Oxford University Press, New York.