Page 139 - Aircraft Stuctures for Engineering Student
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5.1 Pure bending of thin plates 123
Fig. 5.1 Plate subjected to pure bending.
are given by
1 Z
Ex=-, Ey’-
Px PY
Referring to Eqs (1.47) we have
1 1
E
E
&,=-(cJx-vcry); Ey=-(cry-Vcrx) (5.2)
Substituting for E, and from Eqs (5.1) into Eqs (5.2) and rearranging gives
EZ
(5.3)
Ez
cr =-(’+;) 1-2 py
(a) (b)
Fig. 5.2 (a) Direct stress on lamina of plate element; (b) radii of curvature of neutral plane.