Download this stock image: . The action of materials under stress; . Fi^.J3.. Beams which can be cast in form or built up may be madein the above outlines, if desired. Some common examples,such as brackets, girders of varying depth, working-beams,cranks, grate-bars, etc., are more or less close approximationsto such forms. Enough material must also be found at any 74 STRUCTURAL MECHANICS. section to resist the shear, as at the ends of beams supportedat the ends, Figs. 31 to 34. Where a plate girder is used, (see Fig. 96), with a con-stant depth, the cross-section of the flanges, or their thick-ness when their breadth is - 2CDX8FT from Alamy's library of millions of high resolution stock photos, illustrations and vectors.