Recently, environmental protection has become one of the most critical concerns in the global scale. Currently, it is widely recognized that life cycle assessment (LCA) is a very effective instrument to quantitatively evaluate environmental impact of various products across their whole lifecycle. LCA itself is not yet established as a well defined method, but already finding a wide range of applications in electric appliances, automobiles and other industrial products. We conducted a basic survey for LCA of Shinkansen vehicles, as a case study for the railway system. As a result of this survey, we could obtain useful knowledge for applying LCA to the railway.

Hiromichi ISHIDUKA Vehicle Structure Technology DivisionThe use of high-strength flame-resistant magnesium alloy appears to be a promising route to reduce the weight of car body shells. Since research and development of flame-resistant magnesium alloy has just started, basic data and processing technologies still need to be investigated. This paper presents the results of investigations on its test processing, evaluation of its mechanical properties and workability. The trial manufacturing of hollow extruded materials and welding processes using this alloy are also briefly described.

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Recently, environmental protection has become one of the most critical concerns on a global scale. Currently, it is widely recognized that lifecycle assessment (LCA) is a very effective instrument used to evaluate the environmental impact of various products quantitatively across their whole lifecycle. A basic LCA survey of Shinkansen vehicles and cross ties was conducted as a case study for the railway system. Through this study, the following results were con®rmed. For any type of vehicle, more than 95 per cent of lifecycle energy consumption (LCE) and lifecycle CO 2 emission LCCO 2 is attributable to vehicle running. Lightweight vehicles, reduction of running resistance and the use of regenerative brakes contribute to energy saving in vehicle running. Regarding the CO 2 emission from four types of ties (wood, concrete, synthetic and steel), wood ties emit the least amount of CO 2 and synthetic ties the most. When the effect throughout the lifetime is considered, however, wood ties are by no means insigni®cant in terms of the environmental load. As a result of this survey, useful knowledge for applying LCA to railways was obtained. NOTATION Atotal CO 2 emission from all kinds of ties a i energy consumption basic unit of each kind of material (GJ/t) a j energy consumption basic unit (GJ/kl) of fuel, etc. a k CO 2 emission from a tie a total, k total CO 2 emission from type k ties b i CO 2 emission (t/t) basic unit of each kind of material b j CO 2 emission basic unit (t/kl) of fuel, etc. C 1 CO 2 emission (t) at the manufacturing stage C 1M CO 2 emission (t) in the production of raw materials C 1P CO 2 emission (t) in fabrication and assembling C 2 CO 2 emission (t) in operation and maintenance C 2M CO 2 emission (t) in maintenance C 2R CO 2 emission (t) in running C 3 CO 2 emission (t) in the ®nal disposal of waste D running distance (km) across the lifecycle E 1 energy consumption (GJ) at the manufacturing stage E 1M energy consumption (GJ) in the production of raw materials E 1P energy consumption (GJ) in fabrication and assembling E 2 energy consumption (GJ) in operation and maintenance E 2M energy consumption (GJ) in maintenance E 2R energy consumption (GJ) in running E 3 energy consumption (GJ) at the ®nal disposal of waste LCA lifecycle assessment LCCO 2 lifecycle CO 2 emission LCE lifecycle energy consumption M k number of inspections per annum N k number of inspections across the lifecycle n k number of type k ties in Japan P k power consumption in the maintenance factory per annum (kW h) R k electric power basic unit (kW h/km per vehicle) t k lifetime of type k ties U k electric power basic unit at inspection (kW h per inspection per vehicle)The MS was