Experiments and simulation of split Hopkinson Bar tests on sand

18th APS-SCCM; 24th AIRAPT

Church, P.D.^1 ; Gould, P.J.^1 ; Wood, A.D.^1 ; Tyas, A.^2

QinetiQ, Fort Halstead, Sevenoaks, Kent

TN14 7BP, United Kingdom^1

Sheffield University, Sheffield, United Kingdom^2

关键词: Equation of state;    Experimental test;    Lagrangian hydrocode;    Rate independents;    Sensitivity studies;    Split Hopkinson bar test;    Strain rate dependency;    Unconfined conditions;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/500/11/112018/pdf
DOI  :  10.1088/1742-6596/500/11/112018

来源: IOP

【 摘 要 】

Static triaxial cell data and Split Hopkinson Bar data has been generated for well controlled dry and wet sand under confined and unconfined conditions. This has demonstrated that the dry sand is rate independent in its behaviour, whereas the wet sand exhibits a strain rate dependency in its behaviour. Simulations have been performed with the Lagrangian hydrocode DYNA using a Porter-Gould equation of state (EOS) and Johnson-Holmquist type constitutive model. Comparison with the raw strain gauge data is qualitatively reasonable, although some of the details of the trace are not reproduced. Sensitivity studies have also been performed, which has demonstrated some deficiencies in the constitutive model, relating to wave-speed and definition of moduli in a granular material. This has given some insights into how the constitutive model should be improved and which future experimental tests will be required.