The Massachusetts Bay Transportation Authority operates the oldest light rail system in North America, known as the Green Line, with sections dating back more than 100 years. In order to improve accessibility to the Green Line, in 1995, MBTA ordered 100 partial low-floor, double-articulated light rail vehicles (LRVs) from AnsaldoBreda of Italy. These vehicles will operate in consist with existing high-floor, single-articulated LRVs. Some of the challenges faced by the project team are discussed, and some lessons learned that may be of value to other mature light rail operations contemplating such procurements are highlighted. Derailments of the leading axle of the center truck of the No. 8 Low-Floor Car have been the most challenging aspect of the procurement. Following a comprehensive study of the vehicle dynamics and an investigation of the effects of track quality on derailment performance, several modifications were implemented to correct the problems. While some of the characteristics of the Green Line are unique, the important lessons learned can be usefully applied to other procurements involving the introduction of low-floor LRVs to systems with older infrastructure.
展开▼
