摘要: |
Occupant experiments using instrumented crash test dummies seated in commuter rail seats have been conducted on board full-scale impact tests of rail cars. The tests have been conducted using both conventional cars and cars modified to incorporate crash energy management (CEM). Test results indicate that an improved commuter seat design could significantly reduce occupant injuries associated with collisions of CEM railcars. Commuter seats built to specific crashworthiness design requirements can mitigate the increased severity of secondary impacts associated with CEM equipment. In a collision, the leading car or two in a CEM consist may have a more severe longitudinal crash pulse than the leading car in a conventional consist. The crash pulse associated with a leading CEM cab car results in a higher secondary impact velocity between the unrestrained occupant and the seat, when compared to a conventional cab car. This conclusion applies to both rear- and forward-facing occupants. As a result, the seat must absorb more energy, which may cause significant deformation of the seat back, preventing occupant compartmentalization. Compartmentalization is an occupant protection strategy that aims to: contain occupants between rows of seats, provide a friendly impact surface, and prevent tertiary impacts with other objects. |