1.55 In the structure shown, an 8-mm-diameter pin is used at A, and 12-mm- diameter pins are used at B and D. Knowing that the ultimate shearing stress is 100 MPa at all connections and that the ultimate normal stress is 250 MPa in each of the two links joining B and D, determine the allowable load P if an overall factor of safety of 3.0 is desired. Top view Statics : Use ABC as free body. -200 mm–180 mm- /12 mm A B 8 mm K-0.20- 0.18 FA Feo C 20 mm P +8 mm 8 mm E Me = 0 0.20 FA = 0.18 P %3D D 12 mm P= FA Front view Side view

“ 1.55 In the structure shown, an 8-mm-diameter pin is used at A, and 12-mm- diameter pins are used at B and D. Knowing that the ultimate shearing stress is 100 MPa at all connections and that the ultimate normal stress is 250 MPa in each of the two links joining B and D, determine the allowable load P if an overall factor of safety of 3.0 is desired. Top view Statics : Use ABC as free body. -200 mm–180 mm- /12 mm A B 8 mm K-0.20- 0.18 FA Feo C 20 mm P +8 mm 8 mm E Me = 0 0.20 FA = 0.18 P %3D D 12 mm P= FA Front view Side view ”