NUMERICAL ANALYSIS ON DYNAMIC MECHANICAL BEHAVIOR OF CONCRETE

The dynamic increasing factor (DIF) of concrete is normally measured via split Hopkinson pressure bar (SHPB) tests. However, the tested macro-scale DIF-\dot \varepsilon relationship from the specific SHPB test specimens under different strain rates \dot \varepsilon cannot be directly introduced to finite element (FE) modelling. Based on the ANSYS/LS-DYNA and K&C concrete damage model, the SHPB direct tension, split and spalling tests were modelled, and a modified DIF-\dot \varepsilon relationship with both mesh and \dot \varepsilon corrections for dynamic mechanic behaviour of concrete material was proposed for local and non-local damage modelling of concrete respectively, also the numerical application of the nonlocal characteristic length L was detailed discussed. The comparison between the SHPB/impact test modelling and the relevant test results indicated that the proposed doubly corrected DIF-\dot \varepsilon numerical application schemes could properly capture the concrete dynamic mechanical property.