Composites Aboard High-Speed Trains

High-speed trains have several features that distinguish their designs from those of conventional trains, including an increased emphasis on aerodynamics and a heavier impact on infrastructure. This article discusses these features and how manufacturers of high-speed rail vehicles are increasingly using composites to reduce weight and improve aerodynamics. Composite features of three trains--TGV trains made by Alstom, Amtrak Acela Express trains made by Bombardier and Alstom, and the Siemens Velaro--are described. The exterior nose of the TGV train consists of glass/polyester, incorporating woven glass fabrics along with chopped strand mat for added strength. The nose is a solid-laminate structure and is hand layed up in epoxy and polyester tooling. Solid laminate components are also used for some interior features. The Acela train also has a composite nose, which was hand layed up with fiberglass/polyester resin. The material provides sufficient strength to withstand intrusion into occupied areas in a collision at twice the maximum speed of the train. Composite materials are also used for undercarriage covers and for the shrouds that surround the air conditioning units of each car. Siemens's new Velaro incorporates similar composite components because of their aesthetic flexibility, the ability to increase preassembly of the train and the integration of multiple functions in one component. Although lack of familiarity with the materials and their performance characteristics presents a barrier to broader application, all three train manufacturers anticipate growing use of composites for their high-speed trains.