tesi A. Caggiano.pdf - EleA@UniSA - Università degli Studi di Salerno

Chapter 5. Model performance and numerical predictionsσ [MPa]10.08.0ρ f = 6 %6.04.0ρ f = 3 %ρ f = 2 %2.00.0ρ f = 0 %Dramix Fibers0.000 0.002 0.004 0.006 0.008 0.010Figure 5.2: Experimental data [Li et al., 1998] and numerical simulation for SFRC with Dramixfibers.εσ [MPa]10.08.06.0ρ f = 6 %4.02.0ρ f = 3 %ρ f = 2 %ρ f = 0 %Harex Fibers0.00.000 0.002 0.004 0.006 0.008 0.010ε[MPa]Figure 5.3: Experimental data [Li et al., 1998] and numerical simulation for SFRC with Harexfibers.Beyond the general accuracy of the model predictions and, consequently, the soundnessof its assumptions and formulation, the results in Figure 5.2 and 5.3 emphasize thestrong relationship between the mechanical behavior of FRCC and the fiber contentand quality. A progressive transition from the brittle failure mode characterizing thebehavior of plain concrete in tension to a more and more ductile post-peak responsecan be clearly recognized when the fiber content increases.Finally, the diagrams in Figures 5.2 and 5.3 show the different behavior of SFRC basedon Dramix and Harex fibers, both hooked at the end. The more ductile performance96