New Italian Double Deck Coaches: Tests for Car Body Structural Requirement

Modern railway vehicles are requested to achieve improved performances together with higher safety for passengers and crew: for this reason recent European and National Standards claim for more demanding tests for type approval. In this contest, the initial phase of type approval’s tests became very important in order to achieve good results before the on line tests. This paper deals with the set up of test bench to perform type approval tests on carbody, used for the new Italian double deck coaches. This bench is composed by two longitudinal beams headed by two crossbeams: at one side hydraulic actuators are placed in order to apply the requested load. With a simple procedures is available to perform compression test on bumpers and also compression or traction test on a coupler a worm screw it is possible to apply both traction or compression loads to the carbody. At the other side there is only a reaction crossbeam, rigidly connected with the longitudinal member. Moreover a truss structure should be mounted at one end in order to apply the load at higher levels. The reaction is, however, provided at the other side at bumper level, as stated in the European norm EN12663. So, this test bench allowed to perform traction and compression tests, at bumpers level or in higher position (window level or roof). The driving/trailer and the trailer double deck coaches tested with this new test bench will compose the 60 new 5 coaches “Vivalto” regional train of Trenitalia developed from October 2005, with the main following characteristics: - Number of seats/places: 90/126 - Maximum speed: 160 Km/h The first phase regarded compression tests at bumper level. The European Standard (EN 12663) provide for 2 x 1000 kN symmetric load applied on the head beam of the carbody in the bumper zone and for 2000 kN on the coupler area. Moreover diagonal compression tests are requested: this test is performed applying a force up to 500 kN at one bumper, reacting at the opposite side. The test bench is able, with small adjustments, to provide traction test on the couplers, applying up to 1500 kN, as suggested in the EN 12663 Standard for different types of automatic coupler. In addition, the EN standard provides for compression tests at different height, applying high level loads (up to 400 kN) up to the roof level, by means of an auxiliary truss structure between test bench and carbody. Thusthese compression tests were performed in the third phase: 400 kN 150 mm over the bumpers, 300 kN at window level and 300 kN at the roof level. In the full paper the results of the test listed before will be summarised giving the evidence of the great correspondence with the results of FEM calculations.