Economical design of beams and girders normally requires thin webs. With the advancement in welding technology, pre-manufactured beams with built-up sections are gradually replacing beams made of rolled shapes in Europe and Japan. The objective of the proposal is to study the behavior, to failure, of beams and girders with corrugated webs. The investigation will include identification of the most efficient shape of corrugation, and the associated methods of forming and welding. The approach will consist of experimental and analytical investigations of the behavior of beams and girders with corrugated webs under in-plane shear, in-plane bending, and combinations thereof. The results will include semi-empirical methods to predict the ultimate capacity of beams and girders with corrugated webs and a guide to design criteria.