TABLE OF CONTENTS In previous chapters, rigorous methods are described for finding the complete load-deformation response of beam-columns throughout the entire range of loading up to ultimate load. Any rigorous analysis which attempts to cover this behavior is destined to be complex, even in the elastic range. In the plastic or nonlinear range. the analysis is time consuming even for simple cases. However, in many instances, the determination of the maximum loads that a member can carry is of greater practical importance. The development of efficient methods for computing the maximum load in a more direct manner is, therefore. of intense practical interest to engineers.
This chapter is concerned with the development of such methods. Simple approximate methods to calculate the ultimate strength of beam-columns are described. Interaction equations for the maximum strength of beam-columns under various loading conditions are presented. The moment-curvature-thrust ( m- ?-p) relationships as given by the analytical expressions in Chap. 5 are utilized herein for the analysis. The approximate methods described here are useful only for the determination of the maximum strength. They are not, however, suitable for finding the complete load-deformation behavior of beam-columns.
In order to estimate the maximum strength of a beam-column in a simple manner, the deflected shape is often assumed in a convenient form. The deflection function needs not to satisfy all the boundary conditions, but it is to he noted that the accuracy of the approximate solution depends directly on...
