CONSTOR® V/TC drop tests: pre-test analysis using the finite-element method

Abstract

CONSTOR^® is a family of steel–CONSTORIT–steel sandwich cask designs that have been developed with special consideration for an economical and effective method of manufacture by using conventional mechanical engineering technologies and common materials. The CONSTOR^® concept fulfils both the internationally valid IAEA criteria for transport and the requirements for long-term intermediate storage in the USA and various European countries. A full-scale prototype test cask, CONSTOR^® V/TC, of the latest CONSTOR^® design has been developed, with a heat removal capacity of up to 32 kW. A comprehensive drop testing programme consisting of five 9 m drops onto a flat unyielding target and seven 1 m drops onto a punch is to be carried out by BAM at the test facilities in Horstwalde during Autumn 2004, with the first 9 m side drop to be carried out during PATRAM 2004. The drop tests will form part of the application for a transport licence in both Germany and the USA. Extensive pre-test calculations have been performed using finite-element methods. The objectives of the analyses are as follows: (1) As an intermediate step in demonstrating the performance of the package in fulfilling the requirements of 10 CFR 71 and the IAEA transport regulations. (2) To justify the selection of drop tests. (3) To predict the performance of the V/TC in the drop tests. (4) To estimate the strain and acceleration–time history at measuring points to aid the setting up of the instrumentation. (5) To develop an analysis model that can be used in future safety analyses for transport and storage licence applications to confidently demonstrate the performance of the package. This paper will: present an overview of the analyses; discuss the methodology of the analysis, including the design and make-up of the models taking into account the behaviour of the package, the requirements of the licensing regimes and the present and future purposes of the model; discuss the modelling techniques used; present key results from the analyses; and discuss the behaviour of the package.     

Drop test program with half scale model CASTOR® HAW/TB2

Abstract

Federal Institute for Materials Research and Testing (BAM) is the competent authority for mechanical and thermal safety assessment of transport packages for spent fuel and high level waste in Germany. In context with package design approval of the new German high level waste cask CASTOR® HAW28M, BAM performed several drop tests with a half scale model of the CASTOR® HAW/TB2. The cask is manufactured by Gesellschaft für Nuklear Service mbH and was tested under accident transport conditions on the 200 tons BAM drop test facility at the BAM Test Site Technical Safety. For this comprehensive test program, the test specimen CASTOR® HAW/TB2 was instrumented at 21 measurement planes with altogether 23 piezo resistive accelerometers, five temperature sensors and 131 triaxial strain gauges in the container interior and exterior respectively. The strains of four representative lid bolts were recorded by four uniaxial strain gauges per each bolt. Helium leakage rate measurements were performed before and after each test in the above noted testing sequence. The paper presents some experimental results of the half scale CASTOR® HAW/TB2 prototype (14?500 kg) and measurement data logging. It illustrates the extensive instrumentation and analyses that are used by BAM for evaluating the cask performance to the mechanical tests required by regulations. Although some of the quantitative deceleration, velocity and strain values cannot be shown because of confidentially issues, they are provided qualitatively to illustrate the types of measurements and methodologies used at BAM.