ABSTRACT
We conside r a contro l element , dx dy dz, i n a cont inuu m a s show n i n Figur e 3.31. Th e thre e equilibriu m equat ion s ar e obtaine d a s [ 1 - 4 ]
-ex-"
dx
dx
davv do,
dy
do.
dy
dz
da
+ X = 0
dz (3.81)
dy
dz
Note tha t σ Ί ; 8(ί φ j) ar e use d instea d o f τφ φ j), fo r shea r stresses . Nota t ion s and positiv e direction s o f stres s resultant s an d couple s ar e a s show n i n Figur e
5.2, t o avoi d confusion , an d follo w thos e use d b y man y composit e material s
books.
