2012, Article in monograph or in proceedings ()During the previous HVTT conference in Melbourne, results have been presented of a project FORWARD, including eleven different trailer manufacturers, involving testing and modeling activities to establish a practical basis for realistic fatigue assessment as a step towards an improved light-weight trailer design. The present paper describes the next step as part of the follow-up project LIFE (LIfetime Fatique Enhancement), starting with the model-based assessment of a realistic loading history for a semi-trailer. Representative loading conditions in this history, being derived from three weeks of field testing, are then used in Finite Element analyses to estimate fatigue life at a critical high loaded welded connection in the aluminum
trailer chassis. Results are discussed with respect to the order of different loading cycles (Palmgren-Miner number, based on fatigue tests), 3D loading at the weld, the varying weld quality, and the impact of bonded connections in the trailer. These ‘lessons learned’ are interpreted, to result in improved general guidelines in light-weight trailer design.
2010, Article in monograph or in proceedings (Theoretical and Practical Issues in Transport, pp. 106-112)One way to reduce the fuel consumption to payload ratio of heavy vehicle combinations is to reduce the empty trailer weight. This requires an understanding of the vehicle structure, assembly techniques and production process, and of special materials (e.g. high strength steel) with emphasis on strength and fatigue. But in all cases, one needs to have realistic design loads available. This paper describes an approach to determine these loads as a first step in the process. For this purpose, tractor-semitrailer combinations have been tested under normal operational conditions, for a longer period, under monitoring of a large number of measurement data. These data have been transferred into dynamic loading data in terms of forces at each separate wheel and at the king-pin in vertical, lateral and longitudinal direction. The experience with several trailers has resulted in a cost-effective testing procedure, which also allows the assessment of representative loading cycles.