Effect of End Restraint on Column Strength - Practical Applications

The behavior, strength and design of columns constitute a subject area that probably has received more study and discussion than most structural engineering problems. As a result, a large number of increasingly more accurate solutions have been developed, and the design approaches are legion. The basic column is a centrally loaded, pinned-end member. The original solution for the elastic case was provided by Euler in 1759, and advances over the years have incorporated the influences of residual stresses, initial crookedness and load eccentricity, to mention some of the primary factors. Recognizing that columns are rarely, if ever, pinned-end in actual structures, but rather connected to the other components of the structure by a variety of connection types, recent studies have developed solutions that also take into account the effect of end restraint. As can be expected, there is good agreement between theoretically determined column strengths and those obtained in column tests. This has been facilitated by the use of computer programs that can take into account the many column strength parameters, including their random characteristics.