Analysis of flexure-shear behavior of UHPFRC beams based on stress field approach

An adaptation of the Modified Compression Field Theory (MCFT) to grasp the flexure-shear behavior of prestressed or reinforced beams made of Ultra High Performance Fiber-Reinforced Concrete (UHPFRC) is presented. The UHPFRC mechanical behavior is captured using only “stress-strain” relationships obtained from characterization tests and modified with correction factors derived from literature. The model has been checked with respect to complete data of two experimental programs. The predictions of the model agree rather well with the experimental results with an efficient evaluation of the reorientation of the compressive struts with increasing load. The condition for a synergetic contribution to the shear capacity of transversal reinforcement up to their yield strength and UHPFRC is also discussed.