_______________________________________________________________________ PROBLEM (8.21) The stresses acting uniformly at the edges of a thick. rectangular plate are shown in Fig. P8.21. Determine the stress components on planes parallel and perpendicular to a-a. Show the results on a properly oriented element. SOLUTION θ = −30 o σ x = σ y = −120 cos 45o = −84.85 MPa τ xy = −120 sin 45o = −84.85 MPa 84.85 + 84.85 0 + cos(−60o ) − 84.85sin(−60o ) 2 2 = −84.85 + 73.48 = −11.4 MPa σ y ' = −84.85 − 73.48 = −158.3 MPa σ x' = − τ x ' y ' = 0 − 84.85 cos(−60 o ) = −42.4 MPa y’ x o 30 42.4 MPa x’ 11.4 MPa 158.3 MPa Excerpts from this work may be reproduced by instructors for distribution on a not-for-profit basis for testing or instructional purposes only to students enrolled in courses for which the textbook has been adopted. Any other reproduction or translation of this work beyond that permitted by Sections 107 or 108 of the 1976 United States Copyright Act without the permission of the copyright owner is unlawful.