eng Science and Education Publishing American Journal of Mechanical Engineering 2013-11-22 1 7 300 303 10.12691/ajme-1-7-29 AJME20131729 article Władysław Papacz w.papacz@ibem.uz.zgora.pl 1 Piotr Kuryło 1 Edward Tertel 1 Mechanical Department, University of Zielona Góra, Zielona Góra, Poland In this paper, newly-derived equations, leaning on the canons of the classic durability of materials are used for calculation of leaf springs. Analytic relations between displacements, deformations, Young's modulus and external loads are used. The correctness of the method was verified through theoretical and experimental research. Researches were done on composite leaf spring made from polymer and glass fibres. The main value of the new theory is its high similarity with the experimental data. http://pubs.sciepub.com/ajme/1/7/29/ajme-1-7-29.pdf strengthcalculationscrooked beams