Box section metal beam of uniformly varying depth - is made by joining two channels derived without waste from rectangular sheet

摘要

The box section beam (1) for e.g. a steel-frame building is of a uniformly varying depth (d). The beam is fabricated by welding together two 'C' section pieces (1A, 1B) and the pieces are obtd. from a single rectangular sheet without waste. The rectangular sheet is subdivided into two longitudinal trapezoidal pieces, the dividing line extending between e.g. the non-opposite quarter points (4, 5) of the shorter sides. The two pieces are then fashioned into channels of uniformly varying depth, and brought together for intermittent welding (W) into the box section. The section may be filled with concrete when used for structural purposes.