. . .Fig18">18). This may not always be permissible; but, however the difficulty may be met, it should be dealt with as part of the design. For small angles of skew only may it be neglected.

Rivets attaching cross-girder angles to the web will occasionally[25] loosen, probably due in most cases to bad work, together with some circumstance of aggravation, as in the case of a bridge floor consisting of girders spaced 3 feet 6 inches apart, with short timber bearers between, carrying rails. In many girders the top row of rivets, of ordinary pitch and size, had loosened, allowing the web, about 1⁄4 inch thick, a movement of 1⁄8 inch vertically. The rails being very close down upon the cross-girder tops, though not intended to touch, had at some time probably done so, and by “hammering” produced the result described.

Plated floors are often found which are objectionable on account of their inability to hold water, arising sometimes fr. . . Read More