Abstract
Fatigue life of a rubber engine mount made of natural rubber was estimated. In order to develop an appropriate fatigue damage parameter of the rubber material, load-controlled fatigue tests were conducted using fatigue specimens at different levels of mean load. It was shown that the maximum Green-Lagrange strain and the maximum strain energy density were proper damage parameters, taking the mean load effects into account. A fatigue life curve of the natural rubber represented by the maximum Green-Lagrange strain was determined from the non-linear finite element analysis and the load-controlled fatigue test of the fatigue specimen. Fatigue life estimation of the rubber engine mount was finally made by using the maximum Green-Lagrange strain of the engine mount and the fatigue life curve equation of the natural rubber material. Predicted fatigue lives of the rubber engine mounts agreed fairly well with the experimental fatigue lives within a factor of four.