Shear behavior of captive- and short- column effects using different basalt aggregate contents

The captive-column and short-column effects are resulted from constructing nonstructural walls or facades to the structural system which restricts the ability of the column to deformlaterally, or from constructing horizontal structural elements at mid-height of the column leaving the column divided in two short segments, or can dynamically evolve during earthquakes when the nonstructural walls partially damaged leaving part of the column can laterally deform. This research is intended to investigate the shear capacity of these column effects as a result of using different replacement contents of basalt aggregates in medium strength concrete mix. The workability and the mechanical properties of concrete mixes using different basalt aggregates replacement content are measured and a general improvement is observed in the compressive strength and the tensile splitting strength as basalt replacement content increased to 75%. The shear strength of short columns tested under lateral load improves as the replaced aggregates increased. An equation is proposed to estimate the concrete shear strength at various basalt aggregate replacement contents.