Time-dependent material behavior applied to timber columns under combined loading. Part II: Creep-buckling

The first part of the article dealt with the time-dependent deflection behavior, of beam-columns. If a structural element is subjected to compression, the time-dependent material behavior, too, definitely has a major influence on its carrying performance. Creep leads to larger lateral deflections, which are followed by an increasing bending moment according to the theory of second order and, therefore, also by increasing elastic deflection. In standards this problem of the so-called long-term stability is not taken into account. In this second part of the paper, a simple design formula is derived, which enables a reliable prove of long-term stability with the information included in the standards for all possible load combinations.