The impact of confinement active on flexural behavior of composite pipe sections filled with concrete

Document Type : Original Article


1 Scientific Board Member

2 PHD student

3 Member of scientific board


The aim of this study is to investigate the effect of initial pressure applied on wet concrete core samples of the composite tube filled with concrete, and the flexural behavior of composite sections. In this study, the flexural behavior of 12 specimens are studied. The main variable parameters in this study include: Diameter ratio to the thickness of the tubes (20, 30 and 60), the intensity of applied initial pressure (without pressure, low, medium and high) and the type of confinement (active and passive). Finally, flexural capacity, the energy absorption, flexibility, failure mode and cracks in the concrete core at the moment of failure are determined. The results show.
that active confinement created by the initial high pressure, is more suitable in the thinner samples rather than thicker ones. Also it is concluded that, initial pressure will not have adequate effect on the flexural behavior of specimens with D / t = 20. Moreover applying pressure on the samples with D / t = 60 and 30, improved flexural behavior of the samples compared to specimens with passive confinement.


Main Subjects

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