Steel fiber-reinforced prestressed concrete (SFRPSC) members typically have high shear strength and deformation\ncapability, compared to conventional prestressed concrete (PSC) members, due to the resistance provided by steel fibers at the\ncrack surface after the onset of diagonal cracking. In this study, shear tests were conducted on the SFRPSC members with the test\nvariables of concrete compressive strength, fiber volume fraction, and prestressing force level. Their localized behavior around the\ncritical shear cracks was measured by a non-contact image-based displacement measurement system, and thus their shear\ndeformation was thoroughly investigated. The tested SFRPSC members showed higher shear strengths as the concrete compressive\nstrength or the level of prestress increased, and their stiffnesses did not change significantly, even after diagonal cracking due to the\nresistance of steel fibers. As the level of prestress increased, the shear deformation was contributed by the crack opening\ndisplacement more than the slip displacement. In addition, the local displacements around the shear crack progressed toward\ndirections that differ from those expected by the principal strain angles that can be typically obtained from the average strains of\nthe concrete element. Thus, this localized deformation characteristics around the shear cracks should be considered when measuring\nthe local deformation of concrete elements near discrete cracks or when calculating the local stresses.
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