An ultimate-state-based-model for inelastic analysis of intermediate slenderness PSB columns under eccentrically compressive load

Parallel Strand Bamboo (PSB) is a high quality bamboo based composite and has been used as a construction and building material in recent years. The responses of intermediate slenderness PSB columns, whose slenderness ratios are between that of stocky and slenderness columns, subjected to eccentrically compressive load are shown significant nonlinearities. These nonlinearities should be considered when evaluating the loading-carry capacities and deflections of them in the ultimate state. Experiments revealed that the failure of intermediate PSB columns subjected to eccentrically compressive load are dominated by material damage due to the combined actions of compression and bending of P-delta effect. The failure mode in the ultimate state of the columns is such that the fibers at the damage section are crushed in concave side and snapped in convex side. Based on this failure mode, an ultimate-state-based model, which takes the nonlinearities of material and P-delta effect into consideration, was developed in this paper for inelastic analysis of intermediate slenderness PSB columns under eccentrically compressive load. Good agreements can be observed between the results of experiments and that of calculation by using the ultimate-state-based model.