Automation of small sample positioning for mechanical testing in hot cells

Abstract

The main objective of this paper is to propose an improvement and automation of the current mechanical testing procedure of concrete and rock samples in hot cells, i.e. in laboratories designed for radioactive sample testing. The paper describes the effect of radiation on the different components of concrete and consequently on the concrete itself. To give a general idea of sample handling and hot cell operations, safety precautions are prescribed which significantly prolong and complicate the handling of a radioactive rock sample. Video recordings of the tests were used to analyse the progress of the tests. The main issues were the placement of samples off the axis of the compression test machine, sample curvature, compression test machine design and poor recording of sample deformation. New centring stops were introduced to improve the handling of the specimen when placed in the test machine. Additionally, the use of image processing was proposed to evaluate the correct placement of the sample in the test machine. These improvements should lead to easier sample handling and correct results which will serve as a good basis for subsequent numerical analyses.