About the Impact Behaviour of Railway Fastening Systems

On the basis of what established by the Product Technical Specifications - Specifiche Tecniche di Prodotto RFI (STP) - regarding the performance requirements that fastening systems between sleepers and rails should meet to be homologated, a test plant was designed and a procedure to determine the capabilities of the above-mentioned systems to lessen the effects of impact loads was defined. Moreover, specific guidelines concerning the ways in which impacts are generated are not supplied by the same STP. Issues arise in designing the test plant due to the need of guarantee a certain adjustment margin on the drop height as well as on the determination of the weight of the drop mass. Before building the plant, to check that it could perform impact tests in compliance with the Norms specifications, a massive numerical simulation campaign have been carried out. Numerical results allowed to solve optimally the design problem of the test apparatus here proposed.