A. Specify that intermediate stiffeners providing diaphragm connections be fillet welded to the compression flange and fillet welded or bolted to the tension flange or flanges subject to stress reversal.
Commentary: On tension flanges, welded connections are preferred because of the lower cost, but the design of the flange must consider the appropriate fatigue detail category. A bolted connection is acceptable if the cost is justified.
B. For straight bridges, specify that intermediate stiffeners on plate girders without diaphragm connections have a “tight-fit” at the tension flange and be fillet welded to the compression flange.
C. Specify that intermediate stiffeners not used as connection plates on straight box girders be fillet welded to the compression flange and cut back at the tension flange end or on flange subject to stress reversal.