Shear Behavior of Ultrahigh Performance Fiber-Reinforced Concrete Beams. II: Analysis and Design Provisions

Abstract

The safety margin of shear design provisions for ultrahigh performance fiber reinforced concrete (UHPFRC) requires quantification prior to widespread use. To this aim, the results of a dedicated experimental campaign described in a companion paper and available data from the literature have been used. Different models have been tested for predicting the shear-cracking strength and the ultimate shear capacity of UHPFRC beams. The lack of characterization of the tensile UHPFRC behavior often impairs the quality of data obtained from shear tests on UHPFRC beams. This issue has been partially overcome by approximating the UHPFRC postcracking strength under tension from fibers and matrix properties in using the variable engagement model. The safety of the French recommendations for UHPFRC has been confirmed, and improved models for serviceability-limit states prediction and realistic accounting of critical shear-cracking have been developed.