PSI - Issue 6

Laurence A. Coles et al. / Procedia Structural Integrity 6 (2017) 5–10 Coles at al. / Structural Integrity Procedia 00 (2017) 000–000

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approximately this spread of damage in plane of the composite plate with resolution down to 97 µm. Figure 3 below shows the final distribution of averaged damage against the averaged maximum out-of-plane displacement. The damage area for the failure case was taken as the complete 200 mm x 200 mm square area of the specimen.

Figure 3. Average maximum out of plane displacement and damage cloud area for various cases of air blasts

4. Phenomenological Continuum Damage Model

A finite-element phenomenological modelling approach, incorporating a continuum damage scheme together with strain-rate sensitivity and tensile compressive strength asymmetry of the modelled composite material was developed based on a popular failure criteria by Hashin and Puck. It also includes full historical damage tracking for both inter- and intra-ply damage modes. The air blast interaction was then modelled (Fig. 4) employing a Coupled Eulerian Lagrangian (CEL) technique and validated against experimental data. A more detailed analysis of this numerical scheme and results obtained for various levels of air-blast loading of the studied CFRP composite will be published elsewhere.

Figure 4. (a) Propagation of air-blast pressure wave down shock tube towards CFRP specimen; (b) out-of-plane displacement of CFRP specimen as result of air blast