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The traditional freight wagons employ I-beam sections as the main load-bearing structures. The primary loads they carry are vertical (from loading units) and axial (from train traction and buffers). Ease of manufacturing has played an important role in the selection of the I-beam for this role. However, with lightweighting increasingly becoming an important design objective, an evaluation needs to be done to assess if there are other existing or new section profiles (geometry) that would carry the same operational loads but are lighter. This paper presents an evaluation of 24 section profiles for their ability to take the operational loads of freight wagons. The profiles are divided into two categories, namely ???conventional ??? made by wagon manufacturers (including the I-beam)??? and ???pre-fabricated??? sections. For ranking purposes, the primary design objectives or key performance indicators were bending stress, associated deflection and buckling load. Subsequently, this was treated as a multi-criteria decision-making process. The loading conditions were applied as prescribed by the EU standard EN 12663-2. To carry out structural analysis, finite element analysis was implemented using ANSYS software. To determine the validity of the finite element analysis results, correlation analysis was done with respect to beam theory. Parameters considered were: maximum stress, deflection, second moment of area, thickness, bending stiffness and flexural rigidity. The paper discusses the impreciseness related to the use of beam theory since the local stiffness of the beam is neglected leading to an inaccurate estimation of the buckling load and the vertical displacement. Even more complicated can be the estimation of the maximum stress to be used for comparison when features such as spot welds are present. The nominal stress values computed by means of Navier equation lead to an inaccurate value of the stress since it neglects the variations in the local stiffness, which can lead to an increase in the bending stress values. The main objective of the paper is the applicability of particular section profiles to the railway field with the aim of lightweighting the main structure. Sections commonly adopted in civil applications have also been investigated to understand the stiffness and strength under railway service loads. The common approach reported in literature so far makes use either of the beam theory1 or topological finite element approach2 to determine the optimised shape under the action of the simplified loading conditions. Although the previous approaches seem to be more general, the assumptions made affect the optimisation process since the stress state differs from that attained under the actual service load in the real structure. In this paper, the use of complex shape cross sections and detailed finite element models allows to take account of the real behaviour in terms of stiffness distribution and local stress effects due to manufacturing features like welds. The structural assessment carried out with the ...

Within the automotive environment, protection of vulnerable road users (VRU) is now a high profile issue. Owing to this fact, the European Standards for vehicle design are actively seeking to establish a balance between safety and weight of automobiles. Various research groups are working at an International level to develop assessment methodologies to evaluate the ''Aggressivity'' of automobiles. Statistics in Figure 1 indicate a high number of heavy goods vehicle (HGV) -Pedestrian accidents even though on a decreasing trend [1] constitute a real public health problem. To that effect a vital protocol is needed to alleviate this problem by aiming at injury mitigation in such collision scenarios bearing in mind the increasing demand for fuel efficiency, low cost, and low weight alternatives.This paper presents one of the solutions that aim at reducing injury, fatality, or disablement to pedestrians during a HGV-pedestrian crash by employing a novel energy absorbing aluminum ''egg-box'' panel system into the design. Based on the experimental observations, this work satisfies, as part of an EU project APROSYS, [2] its objectives of improving pedestrian safety.Research on potential energy absorbing structures has been going on for over five decades. The studies have been on the deformation and collapse patterns that quantify energy absorption capability for a particular application. Metallic energy absorbers have become popular. Some of the conventional energy absorbers are metal tubes, rings, thin-walled shells, and box-columns. [3,4] Apart from conventional energy absorbers, metallic honeycombs and foams have gained prominence in the recent past for lightweight options but they lag in cost-effectiveness to be employed into vehicle construction. Wierzbicki [5] has researched about the crushing of metal honey-combs. In this work, it was inferred that the structure deformed by means of stationary and moving plastic hinges. In the recent past, metallic foams are gaining increasing interest for their appreciable energy absorption properties and lightweight. Ashby et al. [6] and many others have studied the properties, structure, and design of metal foams. They have been successful in proving the good energy absorption capability of these cellular materials.