Title:
Shear Strength Equation and Database for High-Strength High-Performance Fiber-Reinforced Concrete and Ultra- High-Performance Concrete Beams without Stirrups (Open Source)
Author(s):
Manuel Bermudez and Chung-Chan Hung
Publication:
Structural Journal
Volume:
121
Issue:
4
Appears on pages(s):
185-195
Keywords:
beam shape; closed-form equation; fiber distribution; highperformance fiber-reinforced concrete (HPFRC); hybrid fibers; machine learning (ML); shear-transfer mechanism; size effect; ultra-highperformance concrete (UHPC)
DOI:
10.14359/51740716
Date:
7/1/2024
Abstract:
The study presented a shear strength equation for high-strength
high-performance fiber-reinforced concrete (HS-HPFRC),
including ultra-high-performance concrete (UHPC). This equation
was designed for straightforward implementation, catering to the
regular tasks of engineers. It considers various influences on shear transfer mechanisms, including fiber bridging, fiber distribution,
dowel action, cross-sectional shapes, and beam size effects. The
equation does not rely on uniaxial tensile tests or inverse analysis of
flexural tests; instead, it considers the statistical impact of fibers on
shear strength. To generate the coefficients for this semi-empirical
closed-form equation, an evaluation database of 118 HS-HPFRC
and UHPC beams was constructed. The evaluation results revealed
that the proposed equation has a mean of 1.00 and a correlation
coefficient of 0.92, indicating low variation and high predictive
accuracy. Furthermore, it outperformed existing equations and
matched the accuracy of the machine learning (ML)-based models
including support vector machines (SVM), random forest (RF), and
artificial neural network (ANN), despite its comparatively simpler
expression.