Issue 49

L. Restuccia, Frattura ed Integrità Strutturale, 49 (2019) 676-689; DOI: 10.3221/IGF-ESIS.49.61 686 Figure 11: Load-CMOD curves, series 3. To produce completely recycled materials, Series 4 has been done only for mortar with standard sand (M-SS) and for mortar with 100% of recycled sand (M-RSw 100%). In this case, the amount of SP1 has been maintained at 1% dose, while the w/c ratio has been lowered. In Tab. 9 the results concerning the mechanical tests are reported. The improvement trend follows that of the previous series, as a sign that the increased presence of recycled sand grains can ensure a strong bond with the matrix: this might explain, in fact, the substantial increase in terms of fracture energy G F . Table 9: Mechanical and fracture results, Series 4 (w/c = 0.40; 1.00 % SP1). Figure 12: Load-CMOD curves, series 4. ID Batch P MAX E K IC G F σ f σ c [N] [GPa] [MPa√m] [N/m] [MPa] [MPa] M-SS 1021.14±53.22 6.02±3.98 4.79±3.52 6.40±3.41 7.81±0.41 45.88±2.30 M-RSw_100% 909.10±65.64 4.71±1.21 4.38±1.45 8.65±6.73 6.96±0.50 52.68±5.08