Column design: past, present, future

摘要

The historical development of the different approaches for designing axially-loaded metal columns is presented and critiqued. For completeness ancient column designs of stone and wood prior to the use of iron columns are briefly mentioned. The mathematical, experimental, industrial, professional and political factors that contributed to our current status are presented. Emphasis is placed on determining the underlying factors that led to the use of various formulas. The current single column curve vs the multiple column curve controversy is evaluated. Since the first use of mild steel columns in the 1850's to the present, US design formulas for steel columns actually have changed very little. The appearances of the formulas are different but their outcomes are similar, only the implied factor of safety has been significantly affected. The fact that the early design formulas in the 1880's were based on the theory of columns with imperfections combined with test results, not buckling theory, is the major reason there has been so little change in US practice.