Verification of a New Semidiscrete Beam Model for Fiber-Reinforced Concrete Beams

Abstract

This article shows through the analysis of three independent tests that the presented new semidiscrete analytical (SDA) beam model is efficiently applicable in the evaluation of test results. The model is based on fracture mechanics, takes the real distribution of the macrofibers into consideration in the critical cross-section of the beam, and uses a precise approximation of the pull-out behavior of the fibers. The SDA model is applicable to evaluate synthetic and also steel fiber reinforced concrete beams. Furthermore, it is shown that the new method can predict the changes of the residual loadbearing capacity caused by the different length, diameter, tensile strength, maximal friction stress, or other features of the fiber with the use of only one series of experiments with given fiber parameters (e.g., tests with only one fiber length and diameter). Thus, the application of the SDA model can decrease the cost and time of testing new types of fibers because the required number of samples and, therefore, the total time of the lab tests can be radically decreased.