Erection of Main River Span, Passaic River Bridge

From the erection of the first of the five main spans of the Passaic River Bridge to the final swinging required a period of 70 days. This time interval is short in comparison with the time that is usually required to erect bridges of comparable size. Engineering studies made prior to the beginning of erection accounted for the positions of equipment, delivery of material, and sequences of operations. These studies did much to reduce the time of erection. Of great concern to the erectors were the deflections that the structure would undergo during the erection procedures. These movements, although small to the casual observer, are of considerable importance to the engineer because the members which are fabricated in the shop must, on being lifted into position, fit exactly with the joining members. These studies and other construction problems involved in the erection of the main river span of the Passaic River Bridge are described in great detail.