Cold curving symmetric unstiffened I-girders

Horizontally curved steel girders are usually fabricated using cut curving or heat curving. Cut curving results in excessive waste while heat curving is a trial and error process that can be time consuming. In contrast, cold bending is a simple, versatile, economical procedure in which the required curvature is directly obtained by applying loads. As most cold bending systems developed are proprietary, little published information is available and progress has been stymied. Recently, an innovative cold bending system was developed for fabricating curved steel girders used in the construction of the Miami Metromover. This paper presents a simplified analysis for this system for curving symmetrical, un-stiffened girders. A systematic practice-based curving procedure is proposed and its application illustrated by three inter-related numerical examples.