Cost Analysis in the Design of Open-Web Castellated Beams

Open-web castellated beams have been used for many years, but because of high costs associated with fabrication they have found limited use in the USA. In other countries, however, this type of open-web beams has found widespread use, primarily in buildings because of great savings in materials and construction costs. Also, the open web of castellated beams can lead to the additional economic advantage of allowing easy, fast, and less expensive installation of conduit and utilities throughout the structure without the need for special hanger supports and without an increase in finished floor elevations. Any savings in steel weight because of the use of these beams are also a positive factor as it relates to the overall supporting structural and foundation systems. In addition to the economic and functional advantages aforementioned, these beams maybe used to enhance the aesthetics of buildings. The purpose of the work presented in this paper is to conduct a detailed cost comparison between open-web castellated beams and unaltered standard wide flange beams. For castellated and unaltered standard wide flange beams with equal load capacities our investigation shows that castellated beams are more advantageous, making them very attractive for use in buildings. Particularly when considering large projects where the number of required beams is over one hundred, where castellated beams are economically competitive with unaltered standard wide flange beams.