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This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1917 edition. Excerpt: ...of the hub is assumed. Use 8 inches inside. The thickness of metal must be assumed for trial. Use 1-inch for hub; % inches for top plate; Q' and 1% inches for base plate. "I'iIII'iII'1l!-..L The shaded area in Fig. 152 Fig' 152' SE;',i,'§'_1f§'.,'nC1'3§,'1'e',','.',i',' s"""'"' f shows the section available for resisting bending. To determine its resisting moment R M it is first necessary to locate its-neutral axis and then compute its moment of inertia. The center of gravity is found by the method given on p. 36. The area of the cross section is 105.25 sq. in. Taking moments about the bottom line for a moment = 57.75 X.875 = 50.53 for b moment=32.50 8.25 =268.l2 for d moment=15.00X15.375=230.62 The allowable stress on cast iron in tension is 3000 pounds per square inch. Then the resisting moment of the section is R M = s 1 = W = 1,940,000 in.-lb. c 5.21 The bending moment M, resulting from the pressure on the bottom of the plate, is determined by treating the plate as an inverted cantilever, Fig. 152. Then 111 = 300,000 X 9 = 2,700,000 in.-lb. This amount is excessive because it assumes the column load applied at a point at the center of the top of the olate, whereas it occupies considerable area. ' As the bending moment computed for the load is 2,700,000 inch-pounds and the resisting moment is 1,940,000 inch-pounds, the trial section is not sufficient. The section can be increased in strength by increasing the height or by increasing the thickness of metal. The most effective places for additional metal are in the top and bottom plates. PROBLEM Increase the height of the cast-iron pedestal to 1'-6',...