Generation and validation of loading profiles for highly accelerated durability tests of ground vehicle components

Abstract

Accelerated durability tests are designed to quantify the life characteristics of ground vehicle components under normal use conditions by testing at a higher stress level to accelerate the occurrence of failure. Presently, conducting durability tests with a high acceleration factor has become increasingly demanding for the reduction of the time and the cost involved in long period field/durability tests. In previous work, to accelerate the field test, the standard ‘test tailoring approach’ has been modified due to the limitations of testing implementation and required high acceleration factors. In this modified approach, a full period durability loading profile has to be shortened to an equivalent partial period test loading profile, which is repeated in the tests keeping the same amount of damage contents. To apply this new modified approach to industrial durability tests, it needs to be validated. In this work, a computer-aided testing method is developed for the validation of this modified ‘test tailoring approach’. Hence, a new test-piece has been designed by a conjugative approach involving the finite element technique and fatigue analysis for a specific durability life. Afterwards, the loading profiles with various acceleration factors synthesized via the modified approach have been applied on the designed test-piece and the fatigue lives have been simulated to verify the effectiveness of those loading profiles. Simulation results show that, loading profiles with high acceleration factors can be successfully generated with the accuracy above 95%. In addition, synthesized accelerated loading profiles result failure from the identical locations determined using the proposed conjugative approach.