Behavior of rubberized high strength reinforced concrete columns incorporating polypropylene fibers under eccentric loadings

Abstract This study investigates the behavior of rubberized high‐strength reinforced concrete (RHSRC) columns, including polypropylene (PP) fibers, under eccentric loads. Five distinct concrete mixtures were formulated, wherein natural fine aggregate (NFA) was substituted with crumb rubber (CR) at varying replacement volumes of 0%, 10%, and 20% for the initial three mixtures, and at 10% and 20% in conjunction with PP fibers for the subsequent two mixtures. Fifteen columns were fabricated (three columns from each mixture) and subjected to monotonic loading with eccentricity ratios of e / t = 0.25, 0.5, and 0.75. The results demonstrated that the incorporation of CR adversely impacts the load‐bearing capacity and stiffness of the examined columns. The incorporation of PP fibers in the concrete mitigated and improved these effects. Consequently, the incorporation of a blend of CR and PP fibers may be a suitable option for diverse structural applications. Finally, analytical assessments were conducted utilizing the established nominal axial force‐bending moment (N–M) diagrams of the test specimens to analytically determine the column capacity. The findings validate the capacity of the devised N–M diagrams to precisely forecast the failure loads of the examined columns.