Research is being conducted to develop technical

information needed to formulate effective natural gas fuel

tender crashworthiness standards. This research is being

performed for the Federal Railroad Administration’s (FRA’s)

Office of Research, Development, and Technology, and

intended to facilitate industry efforts to use natural gas as a

locomotive fuel. Strategies to assure crashworthiness during

moderate accidents, such as train-to-train collisions at speeds

up to 40 mph, are being evaluated.

This research applies the approach FRA has used to

develop technical information on locomotive, hazmat tank car,

and diesel fuel tank crashworthiness. There are four primary

tasks:

1. Definition of collision scenarios

2. Evaluation of traditional designs

3. Evaluation of alternative designs

4. Recommendation of effective crashworthiness strategies

The tender scenarios have been drafted from reviews of

freight train accidents and of scenarios developed for

locomotives, hazmat tank cars, and fuel tanks. From these

reviews, five scenarios were selected. These scenarios are

intended to bound the range of collisions that a tender may

experience, are being used to evaluate the crashworthiness of

traditional tender designs, and will be used to evaluate

alternative design tenders. The five candidate scenarios are:

1. Train-to-train collision

2. Grade-crossing accident

3. Tender derailment and rollover

4. Impact into tender tank shell during derailment

5. Impact into tender tank head during derailment

As part of previous research on locomotives and passenger

equipment, a range of crashworthiness analysis techniques

were developed. These include simplified techniques, which

can be performed rapidly and provide essential results, and

detailed computer simulations which provide a wealth of

information. The crashworthiness performance of a

hypothetical tender design has been evaluated using simplified

techniques. Simplified techniques include quasi-static crush

analysis of structural elements and lumped-parameter analysis

of train dynamics. The results suggest that efforts to enhance

crashworthiness should principally be directed toward the trainto-

train scenario. Work is ongoing to develop strategies for

improving tender crashworthiness.

This research is being conducted cooperatively with the

Association of American Railroads (AAR). The research

results are being shared with the AAR’s Natural Gas Fuel

Tender Technical Advisory Group (NGFT TAG). The NGFT

TAG is developing industry standards, including

crashworthiness requirements, for revenue-service natural gas

fuel tenders. There is a companion paper which describes

crashworthiness research sponsored by AAR, including

detailed computer simulations of tender crashworthiness. This

paper describes development of scenarios and simplified

analyses of tender crashworthiness.