Structural behavior of concrete filled double-skin PVC tubular columns confined by plain PVC sockets

Abstract

Abstract The behavior of concrete-filled double-skin poly vinyl chloride (PVC) tubular columns confined by plain PVC sockets is studied in this research. The plastic pipes have been used with concrete as columns. PVC has several advantages as it is inexpensive, light weight for construction, and decrease in the time taken for construction. Thus it can be used as an alternative to metal in various applications in which the maintenance cost is increased and the corrosion is reduced. This study is an experimental work on four groups of composite hollow PVC columns, each group containing three different samples. The effects of several parameters are studied, including slenderness ratio, compactness ratio, compressive strength, and confinement ratio. The experimental results show that stiffness, strength, as well as the ductility of composite columns of different loadings were considerably influenced by all these parameters. An increase in loading carrying capacity by about 40.4% was noticed as slenderness ratio decreased from 20 to 12 and about 21.1% as compactness ratio decreased from 50 to 25. Besides, the rate of increase in load capacity was about 96.6% as compressive strength increased from 33 to 54 MPa. For the case of variation of confinement ratio from 25 to 75%, the increase in the axial load capacity was about 56.7%. The main benefit of this type of column is the interaction between PVC tube and concrete. Besides, restriction of concrete by tube results in the delay of local buckling so that the concrete strength is enlarged by the effect of confining provided by the tube.