Axial compressive properties of round bamboo-fiber reinforced phosphogypsum composite short columns

Bamboo is an ideal green building material with excellent mechanical properties. Phosphogypsum (PG) is a kind of solid waste residue which is in urgent need of resource utilization and has been used as construction material. In this paper, a kind of round bamboo-fiber reinforced phosphogypsum composite short column was proposed. Axial compression tests of pure bamboo columns, bamboo columns filled with phosphogypsum inside, bamboo columns with phosphogypsum outside and bamboo columns with phosphogypsum inside and outside were carried out to explore the failure mode and mechanical properties of the short columns. The effects of the parameters include bamboo node, hose hoops, size of the bamboo tube and the strength of phosphogypsum on the mechanical properties of the short columns were analyzed, and the theoretical calculation method of the bearing capacity of the short columns was put forward. The results show that the bamboo nodes and hose hoops can improve the bearing capacity, initial stiffness and ductility of the column. The larger the size of the bamboo tube, the better the mechanical properties of the short column. The bearing capacity of round bamboo-phosphogypsum composite short column is higher than that of pure bamboo column. The ductility of bamboo columns with phosphogypsum outside is obviously higher than that of pure bamboo columns. The finite element analysis results are in good agreement with the test results. The theoretical calculation method of the bearing capacity of columns considering the strength reduction coefficient, the bamboo node effect coefficient and the constraint effect in this paper has high accuracy.