PSI - Issue 24

Riccardo Scazzosi et al. / Procedia Structural Integrity 24 (2019) 53–65 / Structural Integrity Procedia 00 (2019) 000–000

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The crush mode failure is defined in Eq. (10)

�� � � �� � � � � 〈� � 〉 �� �

� � � � � �

(10)

where S FC is a material input parameter as defined in Table 3. The in-plane matrix mode failure is defined in Eq. (11) �� � � �� � � � �� 〈 �� 〉 �� � � � � � � � where G ab and S ab are the material input parameters as defined in Table 3. The parallel matrix mode failure (delamination) is defined in Eq. (12) �� � � �� � � � �� � 〈 � 〉 �� � � � � �� �� ��� � ��� � � � � �� �� ��� � ��� �

(11)

� � � � � � �

(12)

where S cT , S bc0 and S ca0 are the material input parameters as defined in Table 3. S SRC is defined as ��� � � tan 〈� � 〉 where  is the Coulomb’s friction angle. S is a scale factor introduced to provide a better correlation of the delamination area with experiments. For a complete description of the damage evolution the reader is referred to (Material Science Corporation (MSC) & University of Delaware Center for Composite Materials (UD-CCM) 2017). MAT_162 also accounts for the effect of the strain rate by a logarithmic function on the strength and moduli properties, as defined respectively in Eq. (14) and Eq. (15) � �� � � � � � �� � ����� ln �� ̅ � � �� ��� (14) where C rate1 is a material input parameter as defined in Table 3, {S} = {S aT S aC S bT S bC S FC S FS } and { ̅ } = {|  1 | |  1 | |  2 | |  2 | |  3 | (  31 2 +  23 2 ) 1/2 } � �� � � � � � �� � � ����� � ln �� ̅ � � �� ��� (15) where {E} = {E a E b E c G ab G bc G ca }, { ̅ } = {|  1 | |  2 | |  3 | |  12 | |  23 | |  31 |} and {C rate1 } = {C rate2 C rate2 C rate4 C rate3 C rate3 C rate3 }. (13)