A simple analytical bending stress model of parabolic leaf spring

Abstract

The evaluation of stress distribution, produced by vertical loading along a parabolic leaf spring, presents an essential aspect during the design stage. Commonly, designers utilize the finite element analysis to simulate the stress behaviour of a parabolic leaf spring. Nevertheless, the use of such method is a time-consuming process during the deterministic and the reliability-based fatigue design optimisation. In this study, we propose three analytical models describing the bending stress distribution of a simply supported single asymmetric parabolic leaf spring: (i) an initially curved single asymmetric parabolic leaf spring, subjected to a concentrated load; (ii) a straight single asymmetric parabolic leaf spring, subjected to a uniform load and (iii) an initially curved single asymmetric parabolic leaf spring, subjected to a uniform load. Bending stress distribution results of classical, finite element and proposed models are compared for several case studies. It is observed that the third model is the most precise model compared to the finite element analysis of single asymmetric parabolic leaf spring. Therefore, the suggested model can be used to generate fatigue life diagram that predicts the required mean and alternating load values for a desired fatigue life with an acceptable accuracy and a reduced computational time.