This document presents the stage of knowledge resulting from the Euraxles project about the design of the axle, and further steps to be taken. It is the support: - to define the loads to be taken into account; - to describe the stress calculation method using finite elements and the validation processes associated; - to specify the maximum permissible stresses to be assumed in calculations and the safety factors to be used. This technical report is applicable for: - wheelset Axles defined in EN 13261 as pure wheelset ; - other axle designs such as those encountered in particular rolling stocks e.g. with independent wheels, variable gauges, urban rail& This document has not for aim to replace EN 13103-1 and prTS 13103-2 but to present a complementary method to the existing ones.