An approximate method for the evaluation of the roll stiffness of road tankers

Abstract

The rollover stability of tank vehicles depends on a number of factors that result in a lateral shift of the centre of gravity, which influences roll dynamics in cornering. The most important factors are the height of the centre of gravity, the track width, the axle roll stiffness, suspension and tyre compliance, and suspension roll stiffness. A tilt table test and, alternatively, a calculation method are suggested for implementation by United Nations Economic Commission for Europe (UNECE) Regulation 111. In Greece, no available approved testing rig is available to carry out the required tests for the conformity of those vehicles with Regulation 111 and, consequently, the calculation method is almost exclusively adopted. However, the calculation method for Regulation 111 still remains a theoretical way to check the vehicle behaviour owing to the large number of non-validated physical parameters involved. Thus, there is a lack of reliability between results obtained by the calculation method from different inspection bodies for similar vehicles. A combined experimental and calculation method that determines the overall torsion-angular displacement relation for a vehicle on an inclined level under its own weight is discussed, and results of the application of this method in a large series of various types of road tanker are presented in this paper.