Issue 45

P. Jinchang et alii, Frattura ed Integrità Strutturale, 45 (2018) 156-163; DOI: 10.3221/IGF-ESIS.45.13 159 Figure 1 : The XRD spectra of graphite and graphite oxide. The FTIR spectrum of graphite oxide is shown in Fig. 2. As shown in Fig. 2, the stretching vibration and bending vibration peaks of -OH in water molecule were at 3394 cm -1 and 1622 cm -1 respectively, the the stretching vibration and bending vibration peaks of -OH in hydroxyl group were at 3141 cm -1 and 1401 cm -1 respectively, the stretching vibration peak of - C=O in carboxyl group and carbonyl group at the edge of graphite oxide nanosheets was at 1727cm -1 , and the stretching vibration peaks of C-O-C/-C-O were at 1116 cm -1 and 1075 cm -1 . The existence of those characteristic peaks suggested that oxygen-containing groups such as carboxyl group, epoxy group and carbanyl group were introduced in the preparation of graphite oxide, i.e. graphite has been successfully oxidized. Figure 2 : The FTIR spectrum of graphite oxide. Figure 3. AFM image of graphene oxide nanosheets. AFM image of graphite oxide is shown in Fig. 3. It can be seen from Fig. 3 that the size and thickness of graphite oxide sheet were 100-1000 and 0.7 nm, respectively, indicating that graphite oxide is one or two atom thick layers. It suggested that the prepared graphite oxide with oxygen-containing functional group on the surface had favorable dispersion and peeling. Effects of the Mixing Amount of Graphene Oxide on the Mechanical Properties of the Test Specimens The bending and compressive strength of the prepared graphene oxide reinforced cement based composite material were tested, as the results are shown in Tab. 2 and 3.