huangyhg

high strength bolts
a325 bolts do not react adversely with mild steels. beams are usually bolted in the web, not the flange, though they could be...just more difficult to set up.
bolted splices are usually done with web plates, but can and, sometimes are, bolted at top and bottom flanges, depending on the lateral loading that particular beam is subjected to(it is rare to find this splice specified these days, full penetration welding is faster and cheaper, even in the field). the one drawback, in my area, to using a-325 fasteners in the event that a-307 spec fasteners would have been acceptable for the application is in the inspection process. mild steel bolts need not be 'torqued' in most cases, simply 'tightened by hand', whereas grade 5 and above will require the use of a torque wrench or equivelent method to tighten to published specs. of course this also entails the use of proper inspection and certification (more $$$).
rod

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