Title:
Influence of Fiber Orientation and Section Geometry on the Shear Strength of UHPC Members
Author(s):
Publication:
Web Session
Volume:
ws_F25_AmjadDiab.pdf
Issue:
Appears on pages(s):
Keywords:
DOI:
Date:
10/26/2025
Abstract:
Accurate assessment of the shear strength of ultra-high-performance concrete (UHPC) members is essential to fully leverage the potential of this advanced material in designing the next-generation infrastructure. This study examines the influence of fiber orientation and cross-sectional geometry in improving the evaluation of UHPC beams shear strength. The authors developed a hybrid shear strength model that integrates theoretical formulations based on the Modified Compression Field Theory with parameters derived empirically, as well as analytically. The model also includes a novel expression for the angle of diagonal compressive stresses, developed based on compatibility conditions and experimental observations. The model was validated against a comprehensive database of 534 shear-critical UHPC beam tests compiled from 51 different published studies. The model demonstrated strong predictive performance across a wide range of member configurations, achieving a coefficient of determination (R²) of 0.95, an average experimental-to-predicted strength ratio of 1.05, and a coefficient of variation of 0.27. This presentation introduces the shear strength model, the influence of fiber properties, and the model’s performance compared to experimental UHPC beam tests.