Document Type : Research Paper


1 Department of mechanical Engineering, College of Engineering, University of AL-Qadisiya, Iraq

2 Mechanical Engineering Department, College of Engineering, University of Baghdad, Iraq



Leaf springs are commonly used in the suspension system of automobiles and are subjected to varying stress from dynamic loading leading to failure. An analytical method using formulation and solution technique classical laminated plate theory (CLPT) for design optimization of composite leaf springs under different dynamic loading is presented here. Different ratios of height/ width (h/b), and duration of time effect are conclusions. A numerical method using FEM (Ansys11.0) has been for solving the dynamic stress distribution in composite leaf springs. Both theoretical and numerical results give good agreement and the studies reveal that the model proposition flexibility has a significant influence on the system dynamic behavior and using likelihood with car industry automobile less than 500 kg. per wheel.


  1. ANSYS Release 11.0 Documentation, 2007
  2. E. Mahdi el at, "Light Composite Elliptic Springs for Vehicle Suspension", Composite Structures 75, 2006.
  3. H. A. AL-Qureshi, Automobile Leaf Springs from Composite Materials ", IEM, 2001.
  4. Jen Y. Liu Strength Criteria for Orthotropic Material ICCE, 2001
  5. J.J. Fuentes, et al, "Premature Fracture in Automobile Leaf Springs", Journal Engineering Failure Analysis, 2008.
  6. J. N. Reddy," Mechanics of Laminated Composite Plates and Shells", CRC, 2004.
  7. Mario Paz, "Structural Dynamics", Van Nostrand Reinhold Company, 1980.
  8. Rajendran, S. Vijayarangan, "Optimal Design of a Composite Leaf Spring Using Genetic Algorithms", Journal Computers and Structures, 2001.
  9. Robert M. Jones, "Mechanics of Composite Materials", McGraw-Hill, 1975.
  10. Shahriar Tavakkoli et al, Analytical Prediction of Leaf Spring Bushing Load Using MSC/NASTRAN and MID/ , Automated Analysis Corporation Michigan, 1992.
  11. Singiresu S. Rao, "Mechanical Vibrations ", Hall,2005
  12. S. Swanson, "Advanced Composite Materials", Hall, 1997.
  13. Thoatsanope Kamnerdtong et al, "Linear and Nonlinear Finite Element Analyses of a Multi-Leaf Spring in Light Truck",, 2005.