PSI - Issue 67

Shohana Iffat et al. / Procedia Structural Integrity 67 (2025) 1–7 Iffat et al. / Structural Integrity Procedia 00 (2024) 000–000

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Fig. 3– SEM micrograph of concrete structure after 7 days of curing (a) control sample (b) 0.05 wt% of GONR-amended cement concrete.

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Fig. 4. SEM micrograph of cement concrete structure after 28 days of curing (a) control sample (b) 0.05 wt% GONR-amended cement concrete.

Instead, as a result of the progressive hydration of cement particles, after 28 days of curing there was no glaring difference in the amount and distribution of C-S-H phases in unamended concrete (Fig. 4a) and GONR-amended concrete (Fig. 4b). 4. Conclusions The following conclusions are drawn. • Stable aqueous suspensions were obtained for oxidized GONRs with oxygen content of 32.3 O% and 41.3 O%, in concentrations suitable for the manufacturing of nanoamended concrete with GONR concentration of 0.0005 wt% to 0.05 wt%.