Investigation on UPVC confined RC columns with Recycled Aggregate Concrete using C&D waste

Recycled Aggregate Concrete (RAC) is attracting world-wide research interest. Despite its promising impact on environment and economy, use of RAC has been limited to non-structural purposes mainly due to its poor performance (such as lower strength/stiffness, poor durability, higher creep, shrinkage). A possible approach to use RAC as a structural element is confinement of RAC. This study aims at the introduction of a new sustainable composite material which is reinforced RAC filled unplasticized polyvinyl chloride (UPVC) tubular columns. In this present investigation, 81 cylindrical specimens consisting of 54 confined specimens and 27 unconfined specimens have been examined under axial compression. It is found that UPVC tubes can be used effectively for good confinement of reinforced RAC columns as it enhances load capacity and ductility of RAC columns significantly. Capacity equation from Eurocode 4, as well as various confining models available for conventional concrete confined by steel tubes, have been modified and used to calculate peak compressive load of RAC filled UPVC tubular columns in order to compare and assess its potentiality & suitability in the understanding actual behavior of such a system.