## 3 Results and Discussion  
An area of 6.1 \(\times\) 6.5 mm\({}^{2}\) was measured in carbon fabric reinforced composite (Figure 6a1-c1), showing a circular deformation on this composite surface. In longitudinal and transverse directions, broken fiber bundles in carbon fabric reinforced geopolymer composite were seen (Figure 6a2-c2), and the gap between the fibers became larger near the back side of the impact. The depth of the hole was about half the thickness of the specimen and seemed to be thicker at the center of the impact. For E-glass reinforced composites (Figures 7 and 8), the notch formation in the central region was much more pronounced than in the carbon fibers. Comparing Figures 4 and 7, it is clear that the damage stretched over a much wider area. Figure 6: Slices and top view of the carbon fabric reinforced geopolymer composite after impact, a slice of (**a1–c1**) longitudinal and (**a2–c2**) transverse direction of the damaged area. The lines indicate where the other cross sections were taken. (**d1–d2**) Shows the response from the damaged area. Figure 7: E-glass fiber composite after impact. \(\mu\)CT slices of damage from the center towards the edge. The fiber damage was investigated at the center and from each set of pictures, one picture was chosen at a distance of 5 mm towards the edge of the composite. Even in the top layer, the fiber rupture was more pronounced, which was evident from the slices in a longitudinal and transverse directions (Figure 9a1-c1,a2-c2). Figure 8: 3D image after impact test of E-glass fiber reinforced geopolymer composite. The part shows the area of impact. Figure 9: Slices and top view of the E-glass fabric reinforced geopolymer composite after impact test in longitudinal (**a1**-**c1**) and transverse (**a2**-**c2**) directions (the lines indicate where the other cross sections were taken). (**d1**-**d2**) The response from the damaged area. Fiber sliding was observed in the composite due to the slippery behavior of E-glass fabrics and the weak bonding between the fiber and the matrix of the composite. Fiber delamination on the various layers was observed in the composite in the area range of 50 mm towards its longitudinal direction. The slipping behavior of fibers within the matrix of the composite, as well as the loosening of the matrix within the damage zone, was very prominent. The depth of the hole was about twice the thickness of the sample. On the backside, fiber bundles were broken. Thus, the number of layers decreased when one approached the center of impact. This explains why the composite seemed to be thinner in the region of the impact. The impact on the basalt geopolymer composite (Figure 10) was penetrated through its surface. There was extensive damage in the central area that spread out until the edge (Figure 10, slice 450). The specimen was completely deformed, and even the regions outside the impact zone remained permanently twisted due to the impact, as is clearly shown from the top images in Figure 10 where the two \"flat\" parts no longer lay in the same plane. As a result, the remainder of the composite could only carry very negligible loads compared to the original value before the damage [23]. The overall image of the basalt fiber reinforced geopolymer composite is shown in Figure 11. The impact area was observed with a fiber rupture region from the top along the direction of the central impact rupture. Figure 10: Basalt fiber composite after impact. \(\upmu\)CT slices of damage from the center towards the edge. The fiber damage was investigated at the center and from each set of pictures, one picture was chosen at a distance of 5 mm towards the edge of the composite. The effect of the impact was very clear in the longitudinal and transverse directions (Figure 12a1-c1,a2-c2). Figure 11: \(\mu\)CT analysis before and after the impact test of basalt fiber reinforced geopolymer composite. The part shows the area of impact.