Shear Behavior of Ultra-High-Performance Concrete Beams Reinforced with High-Strength Steel Bars

摘要

This study was conducted to investigate the effects of key structural parameters on the shear behavior of non prestressed ultra-high performance concrete (UHPC) beams passively reinforced with high-strength steel bars. The parameters studied were shear span to effective depth ratio a/d; volume fraction of steel fibers V-f; longitudinal reinforcement ratio rho; and stirrups spacing s. Ten beam specimens with cross-section dimension (width x depth) 5.91 x 8.86 in. (150 x 225 mm) were quasistatically loaded to failure on a simple span length of 68.9 in. (1.75 m), under a four-point loading configuration. The statistical analysis of the experimental data indicated that a/d, V-f, and s have significant effects on the shear capacity of UHPC beams, while the effects of p are quite insignificant. A mechanistic model for estimating the shear capacity of reinforced UHPC beams was developed, validated, and shown to be reasonably accurate.