Sensitivity of total strain energy of a vehicle structure to local joint stiffness

This paper discusses how the total strain energy of a vehicle structure is affected by local joint stiffness. By using the principle of virtual work and the minimum strain energy theorem, a closed-form expression for the sensitivity coefficient has been derived. The insensitivity of the total strain energy of a vehicle structure to a particular joint, when its stiffness exceeds a certain value (or threshold value), has been proved mathematically. In order to investigate the sensitivity of the structure to the joint stiffness, a "stick" model has been created and its results have been compared to the test data for accuracy. Some data on joint stiffness of tested vehicles are also presented.