Changes in the steel construction and design codes allow much lighter steel frames before concrete than previously considered practical. This is done by using thinner, narrower steel sections and by allowing higher stresses in them.
In an 18-month period, the author worked with contractors in the Baltimore area on four buildings and one bridge where serious instability of unbraced steel was found during erection and concreting. In each case the steel was loaded five to seven times its unbraced and unconcreted load rating. In no case did the designer say so. In no case did the designer tell the contractor to brace, to shore, or even to have someone check out the frame before construction for the construction loads that would be applied. Concrete people, watch out! Releasing steel design drawings without extensive notes to the builders regarding necessary bracing--when you know the beams or columns cannot safely stand without being braced--is the same as loading and cocking a gun, then handing it to someone who doesn't know what it is.