Shock Environments for the Nuclear Fuel Transportation System (Transportation Platform, Cask, Basket, and Surrogate Assemblies) during Specialized Rail Tests

In 2017 a team from Sandia National Laboratories (SNL) conducted an international 8-month, 9,400-mile test to simulate transportation scenarios for spent nuclear fuel (SNF). The purpose of this project was to quantify the shocks and vibrations environments during normal conditions of transport. SNL conducted this test in collaboration with Pacific Northwest National Laboratory (PNNL) and ENSA (nuclear equipment global supplier). It involved coordination with an international shipping company (COORDINADORA), Korea Radioactive Waste Agency (KORAD) and Korea Atomic Energy Research Institute (KAERI), the Association of American Railroads (AAR), and Transportation Technology Center, Inc. (TTCI). Testing was performed using an ENSA ENUN 32P cask. An instrumented transportation cask containing surrogate fuel assemblies from the US, Spain and Korea was transported by truck in Spain, by barge to Belgium, by ship to Baltimore, and by rail to Colorado for rail tests at TTCI and back to Baltimore by rail. Six terabytes of data were collected over the 54-day, 7-country, 12-state, 9,400 miles of travel. For the first time, strains and accelerations were measured directly on the surrogate nuclear fuel assemblies and on the basket. The accelerations were measured on the cask, cradle, and transportation platform. A total of 40 accelerometers and 37 strain gauges were used. The analysis of the transportation test data was performed in 2018. This paper presents the results of the tests conducted at TTCI. The other results are presented in the three related PATRAM 2019 papers. The TTCI tests were short-duration tests with known conditions and with the design parameters (track design, speeds, and coupling impact velocities) somewhat beyond expected commercial railroad conditions. These tests provided valuable insights on the responses of the transportation system to different types of transient inputs in 125 test cases. The tests addressed the following conditions: Twist and Roll, Pitch and Bounce, Dynamic Curve, Class 2 rail track, Single Bump, Crossing Diamond, Hunting, and Coupling Impact. The TTCI tests with the highest accelerations and strains (except Coupling Impact Test) were: Single Bump, Pitch and Bounce, and Hunting. The Coupling Impact Test, particularly at high velocity, was the most severe event observed.