/FAIL/SPALLING
Block Format Keyword Describes the Spalling and JohnsonCook failure model.
Format
(1)  (2)  (3)  (4)  (5)  (6)  (7)  (8)  (9)  (10) 

/FAIL/SPALLING/mat_ID/unit_ID  
D_{1}  D_{2}  D_{3}  D_{4}  D_{5}  
${\dot{\epsilon}}_{0}$  P_{min}  I_{fail_so} 
(1)  (2)  (3)  (4)  (5)  (6)  (7)  (8)  (9)  (10) 

fail_ID 
Definitions
Field  Contents  SI Unit Example 

mat_ID  Material
identifier (Integer, maximum 10 digits) 

unit_ID  Unit Identifier (Integer, maximum 10 digits) 

D_{1}  1st
parameter. (Real) 

D_{2}  2nd
parameter. (Real) 

D_{3}  3rd
parameter. (Real) 

D_{4}  4th
parameter. (Real) 

D_{5}  5th
parameter. (Real) 

${\dot{\epsilon}}_{0}$  Reference strain
rate. (Real) 
$\left[\frac{\text{1}}{\text{s}}\right]$ 
P_{min}  Pressure cutoff. (Real < 0) 
$\left[\text{Pa}\right]$ 
I_{fail_so}  Failure model flag.
(Integer) 

fail_ID  Failure criteria identifier. 3 (Integer, maximum 10 digits) 
Comments
 This failure model is available for Solid only.
 In this model two models are
combined. The first one is the JohnsonCook failure model, and the second one is
the Spalling model (Spall is detected if (P = P_{min}), the deviatoric stress is set to zero and pressure is required to be
compressive).
(1) $${\epsilon}_{f}=\left[{D}_{1}+\text{}{D}_{2}\u200a\hspace{0.17em}\mathrm{exp}({D}_{3}{\sigma}^{*})\right]\left[1+{D}_{4}\mathrm{ln}\left({\dot{\epsilon}}^{*}\right)\right]\left[1+{D}_{5}{T}^{*}\right]$$Where, ${\sigma}^{*}=\frac{{\sigma}_{m}}{{\sigma}_{VM}}$
 ${\dot{\epsilon}}^{*}=\frac{\dot{\epsilon}}{{\dot{\epsilon}}_{0}}$
 T*
 Is computed in the material law, if this one is thermo plastic, like /MAT/LAW4 (HYD_JCOOK).
 The fail_ID is used with /STATE/BRICK/FAIL and /INIBRI/FAIL. There is no default value. If the line is blank, no value will be output for failure model variables in the /INIBRI/FAIL (written in .sta file with /STATE/BRICK/FAIL option).