Direct strength method and continuous strength method for cold-formed lean duplex stainless steel columns

摘要

The direct strength method and continuous strength method are gaining increasing acceptancernin design of stainless steel columns. This study investigates the applicability of these design methods for coldformedrnlean duplex stainless steel columns, which is a relatively new high strength material with low nickelrncontent. Available data were collected and compared with design strengths calculated from the direct strengthrnmethod for stainless steel and carbon steel columns as well as the continuous strength method. It is shown thatrnthese design methods are generally conservative to predict the column strengths. The direct strength methodrnfor stainless steel using tangent modulus approach to determine the column buckling strength provides accuraternpredictions, but this method involves iterative process in the calculation. Modified direct strength method forrnstainless steel using explicit strength method to determine the column buckling strength is proposed in this paper.rnIt is shown that the modified direct strength method is capable of predicting the column strengths accuratelyrnwith a relatively simple calculation procedure.