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R. A. Khushnood et alii, Frattura ed Integrità Strutturale, 34 (2015) 534-542; DOI: 10.3221/IGF-ESIS.34.59 537 Preparation Scheme The entire preparation comprised on two major steps. In the first step, nano/micro carbonized raw bagasse fibers (CRBF) were dispersed in water with the aid of surfactant and bath sonication for 15 minutes. While in the second stage, the resultant homogeneous solution was mixed with cement using a mechanical mixer operated at 440 rpm (slow mixing) for 1.5 min and at 660 rpm (fast mixing) for 2.5 min. Mixed cement formulations were poured in associated labeled plexi-glass molds of 20 x 20 x 75 mm 3 in size. The molded specimens were kept in covered plastic box partially filled with water for initial 24 hrs. After that the specimens were demolded and immersed water curing was performed at room temperature (20±2 o C) for 28 days [23]. Characterization of Materials and Composites To characterize the structural order of CRBF particles, Raman spectroscopy was performed by means of Renishaw micro- Raman analyzer with green laser of 514 nm wavelength. The Raman spectrum was restricted in the wavenumber range of 500-3500 cm -1 . To analyze morphology, microstructure, elemental composition, cracking pattern as well as the dispersion aspects of CRBF formulations, Field Emission Scanning Electron Microscopy (FE-SEM) along with Energy Dispersive X-Ray (EDX) spectroscopy was carried out. For the evaluation of fracture properties three point bending tests were performed on 28 days moist cured (at 20 o C) prismatic specimens of 20*20*75 mm 3 in size according to the standard set forth in ASTM C348 [24]. The rough surfaces of specimens were smoothened with the help of rotary polishing device via #180 wx-flex paper. A standard 6mm deep notch was carefully machined in the center of each specimen using Remet type TR100S, s/n 3714 abrasive cutter with 2mm thick diamond cut-off wheel. Finally notched specimens were tested using ZwickiLine z010 single column flexural testing machine having maximum load capacity of 1kN as shown in Figure 2, under CMOD (Crack Mouth Opening Displacement) control mode with crack opening rate fixed at 0.003mm/min. Highly accurate and sensitive extensometer (clip on gauge) was employed for the measurement of crack opening and the data was digitally recorded. Figure 2 : Experimental setup for the CMOD controlled three point bending test R ESULTS AND DISCUSSIONS Raman Spectra Analysis aman spectroscopy was performed to explore the presence of structural defects on the surficial periphery of CRBF particles. The two most prominent bands in this regard are I D and I G commonly known as defect grade and graphitization grade respectively which usually occur in the wavenumber range of 1000-1700 cm -1 . The Raman spectrum of CRBF particles displayed the two distinct grades at 1346 cm -1 and 1592 cm -1 wavenumbers as given in Figure 3. The ratio of I D to I G band is about 0.93 which indicates that the CRBF particles contain a limited amount of amorphous carbon or of defective graphitic crystals in these materials [25]. Morphology and Composition SEM micrographs shown in Figure 4a demonstrated that carbonized particles of bagasse fibers are in the form of plates/flakes with shape varying from angular to flat and elongated. These plates exhibit glossy and smooth texture with