Issue 60

A. Elakhras et alii, Frattura ed Integrità Strutturale, 60 (2022) 73-88; DOI: 10.3221/IGF-ESIS.60.06

a)K IC -CTODc curves

b)Relationship between S.D. and CTODc

Figure 7: MC-FD FRC at max stress at different L/d ratios equals 4, 5 and 6.

Tab. 3 shows the proposed parameters of ETPFM for MC-FD FRC and MC-FGC at first cracking and maximum stress. It is clear that K IC S values for MC-FRC and MC-FGC showed an inversely proportional to L/d ratios, as known. Ouyang et al. [26] calculated the fracture properties of NSC by its suggested method, equivalent TPFM, based on experimental results of Bažant and Pfeiffer [43]and showed agreement with the results of SEL. Four different beams with a constant L/d ratio equal to 2.50, f cu =33.5MPa, and E= 27.7GPa were investigated. The results of ETPFM parameters of NSC were K IC =0.99 MPa.m 0.5, and C f =11.12 mm. As known, the K IC values are inversely proportional to L/d ratios, so

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