Issue 33

Y. Wang et alii, Frattura ed Integrità Strutturale, 33 (2015) 345-356; DOI: 10.3221/IGF-ESIS.33.38 349 After determining the direction of the maximum variance, the shear strain resolved along this direction, MV ( ) t  , can directly be evaluated, at any instant, t , of the load history, through the following relationship:   x xy xz MV xy y yz xz yz z 1 1 ε (t ) (t ) (t ) 2 2 1 1 γ (t ) ε (t ) γ (t ) 2 2 2 1 1 γ (t ) γ (t ) ε (t ) 2 2 x x y z y z n t q q q n n                                     (14)                                                              n n n n n n n n n n n n n n n t t t k                      , , )( Var , , )( Var , , )( Var q q q 1 1 1 Figure 2 : Flowchart summarizing the algorithm for the determination of the critical plane orientation. The shear stress resolved along the maximum variance direction, MV ( ) t  , and the stress normal to the plane experiencing the maximum variance of resolved shear strain, n ( ) t  , can be evaluated, at any instant, t , of the load history, through the following relationships:   x xy xz MV xy y yz xz yz z (t ) (t ) (t ) (t ) (t ) (t ) (t ) (t ) (t ) x x y z y z n t q q q n n                                    (15)