Proceedings of the 2004 ASME/IEEE joint rail conference

PDFProceedingsRTD2004-66045CrashworthinessImpact testsCollisionsEnergy absorptionPassenger carsCommuter carsPassenger compartmentsMeasurementSpeed measurementAccelerometersDynamic testsDynamic structural analysisCrash injury researchUnited StatesAmerican Society of Mechanical EngineersInstitute of Electrical and Electronics EngineersJacobsen, KarinaTyrell, DavidPerlman, BenjaminJohn A. Volpe National Transportation Systems Center (U.S.)Tufts UniversityAGR-SAFETY AND SECURITY-SAFETY AND SECURITYNTL-RAIL TRANSPORTATION-Rail SafetyNTL-SAFETY AND SECURITY-Rail SafetyNTL-SAFETY AND SECURITY-Vehicle DesignVolpe National Transportation Systems Center, Technical Reference CenterOn December 3, 2003, a single-car impact test wasconducted to assess the crashworthiness performance of amodified passenger rail car. A coach car retrofitted with aCrash Energy Management (CEM) end structure impacted afixed barrier at approximately 35 mph. This speed is justbeyond the capabilities of current equipment to protect theoccupants. The test vehicle was instrumented withaccelerometers, string potentiometers, and strain gages tomeasure the gross motions of the car body in three dimensions,the deformation of specific structural components, and theforce/crush characteristic of the impacted end of the vehicle.The CEM crush zone is characterized by three structuralcomponents: a pushback coupler, a sliding sill (triggering theprimary energy absorbers), and roof absorbers. Thesestructural mechanisms guide the impact load and consequentcrush through the end structure in a prescribed sequence.Pre-test activities included quasi-static and dynamiccomponent testing, development of finite element and collisiondynamics models and quasi-static strength tests of the endframe. These tests helped verify the predicted structuraldeformation of each component, estimate a force-crush curvefor the crush zone, predict the gross motions of the car body,and determine instrumentation and test conditions for theimpact test.During the test, the passenger car sustained approximatelythree feet of crush. In contrast to the test of the conventionalpassenger equipment, the crush imparted on the CEM vehicledid not intrude into the passenger compartment. However, asanticipated the car experienced higher accelerations than theconventional passenger car.Overall, the test results for the gross motions of the car arein close agreement. The measurements made from both testsshow that the CEM design has improved crashworthinessperformance over the conventional design. A two-car test willbe performed to study the coupled interaction of CEM vehiclesas well as the occupant environment. The train-to-train testresults are expected to show that the crush is passedsequentially down the interfaces of the cars, consequentlypreserving occupant volume