Users:General FEM Analysis/Materials Reference/Puck Failure Criterion

General Description

It is based on Mohr‘s fracture hypothesis which is appropriate for brittle fracture behaviour of composite materials. It can distinguish between fibre fracture and different inter-fibre fracture. Both 2D and 3D formulations are implemented into Carat++. Available fracture modes for 2D Puck Criterion are:

• Fibre Fracture (FF)
• Inter Fibre Fracture Mode A (IFF A)
• Inter Fibre Fracture Mode B (IFF B)
• Inter Fibre Fracture Mode C (IFF C)

Available fracture modes for 3D Puck Criterion are:

• Fibre Fracture (FF)
• Inter Fibre Fracture (IFF)

Parameter Description

Compulsory Parameters
Parameter	Values, Default(*)	Description
EF	real	Elasticity modulus of the fibres
RTL	real	Resistance to longitudinal tension (Direction 1)
RCL	real	Resistance to longitudinal compression (Direction 1)
RTT	real	Resistance to transverse tension (Direction 2)
RCT	real	Resistance to transverse compression (Direction 2)
RSL	real	Resistance to longitudinal shear
VFF	real	Volume fraction of the fibres
PTTL	real	Inclination parameter,
PCTL	real	Inclination parameter, p
Optional Parameters
Parameter	Values, Default(*)	Description
STRESS TYPE	2D, 3D	Indicates what kind of stress state should be used to calculate the failure condition. When not given, related element’s stress type is taken.
NUE12F	real	Poisson’s ratio for fibres. (De f ault = 0.2)
MGF	real	Amplification factor (De f ault = 1.2)
S, M	real	Parameters necessary for calculation of weakening due to X1 (De f ault = S = M = 0.5)
PTT	real	Inclination parameter p??. When not given, calculated using the strength values. See Section 3.1.2.3
WEAKENING	int	Switch for calculation of weakening due to _1. 0 = OFF 1* = ON
FPS	SWS*, GSS	Switch for fracture plane search algorithm. SWS* = Stepwise Search Algorithm GSS = Golden Section Search Algorithm
FPS_SWS_SIZE	real	Step size for step-wise fracture plane search