MATERIAL MODELLING AND IMPACT ANALYSIS OF POLYURETHANE FOAM FILLED T 2 0 TRANSPORTATION PACKAGES

Packages used in the road transponation of tritiated heavy water (T 20) must demonstrate the ability to withstard severe shocks and impacts, such as those prescribed by IAEA Regulations. The paper describes part of the analytical assessment of a proposed package design to determine its structural integrity under impact conditions resulting from postulated accidents. The focus of the work described is on the mathematical modelling of the polyurethane foam used in the sandwich construction of the overpack and on the development of acceptance criteria to evaluate the design. Versions of the computer codes DYNA3D and HONDO incorporating these material models were utilized in performing the numerical computation. Comparison of the predicted results of a punch drop with those of experiments show exceUent agreement. Results of the I m punch drop and the 9 m edge drop on the lid end are presented. The proposed design meets the specified acceptance criteria, thus demonstrating it will retain its structural integrity under the impact conditions imposed.