Residual Tensile Stress Estimation for Shear Strength of UHPC Nonprismatic Beams

Estimating the shear strength of Ultra-High-Performance Concrete (UHPC), with high compressive and tensile strengths, is complicated by many variables that affecting its behavior. Residual tensile stress (RTS) plays an important role in raising the efficiency of both types of resistance, especially shear strength due to the presence of steel fibers, which makes it difficult to quantify the residual tensile stress due to the different failure patterns of these fibers and the distribution mechanism within the concrete matrix. There is no study to date in assessing residual tensile stress of UHPC structural members of the variable section. Thirteen beams were selected as an experimental program to study six main variables in determining shear strength. Stirrups ratio, flexural reinforcement ratio, the volumetric fraction of steel fibers, geometry changing, existing openings along the longitudinal axis, and shear span to depth ratio. According to on Tests results, RTS is compatible with most of the global specifications.