## 3 Results Analysis and Discussion  
The base pressure settlement curves obtained in this study as a result of the evaluation of other parameters according to fiber types and the corresponding bearing capacity ratio values were obtained as follows. Glass Fiber;  
The average base pressure-settlement curves obtained according to different fiber lengths, different fiber percentages, and different reinforcement layer depths as a result of model loading tests on sand soil randomly reinforced with glass fiber at Dr = 30%, and Dr = 50% are shown in Figure 5, and the reinforcement depth-bearing capacity ratio relationship is given in Figure 6.  
In glass fiber-reinforced soils, the highest ultimate bearing capacity (qu) was determined as 440 kPa in the case of adding glass fiber to the sand at Dr = 50%, Fc = 2%, Fl = 48 mm, and 3B reinforcement depth. The highest bearing capacity ratio (BCR = final bearing capacity of reinforced soil/final bearing capacity of unreinforced soil) was determined as 6.7 by adding glass fiber to sand at Dr = 30%, Fc = 2%, Fl = 48 mm, 3B reinforcement depth. * For all fiber lengths and percentages at Dr = 30%, there was a 48-73% increase in BCR when reinforcement depth was changed from B to 2B, and there was a 30-52% increase in BCR when changed from 2B to 3B. At Dr = 50%, there was a 94-153% increase in BCR for all reinforcement lengths and percentages from depth B to 2B and an 11-23% increase in BCR from 2B to 3B. Changing the reinforcement depth from 2B to 3B at Dr = 50% had no effect on ultimate bearing capacity as much as the percentage increase seen at Dr = 30%. * Changing the glass fiber length from 24 mm to 48 mm at all reinforcement depths and contents at Dr = 30% increased the BCR in the range of 16-39%. Changing the content of reinforcement from 1% to 2% at all reinforcement depths and lengths increased the BCR between 28% and 61%. Changing the glass fiber length from 24 mm to 48 mm at all reinforcement depths and percentages at Dr = 50% increased BCR in the range of 5-41%. Changing the percentage of reinforcement from 1% to 2% at all reinforcement depths and lengths increased the BCR between 6% and 45%. The increase in bearing capacity ratios obtained as a result of increasing the fiber length from 24 mm to 48 mm by increasing the fiber percentage from 1% to 2% in 50% relative density glass fiber-reinforced soils is similar. However, the increase in BCR obtained as a result of increasing fiber content in soils with 30% relative density glass fiber is higher than the increase in BCR obtained as a result of increasing fiber length. The average base pressure-settlement curves obtained according to different fiber lengths, different fiber percentages, and different reinforcement layer depths as a result of model loading tests on sand soil randomly reinforced with macromesh fiber at Dr = 30% and Dr = 50% are shown in Figure 7, and the reinforcement depth-bearing capacity ratio relationship is given in Figure 8.  
Figure 6: Variation of bearing capacity ratio (BCR) with reinforcement depth (Dr = 30–50%, Fl = 24–48 mm, Fc = 1–2%, and glass fiber). Figure 8: Variation of bearing capacity ratio (BCR) with reinforcement depth (Dr = 30-50%, Fl = 24-48 mm, Fc = 1–2%, and macromesh fiber). Figure 7: Average base pressure-settlement curves obtained as a result of model tests on sand soil randomly reinforced with macromesh fiber: (**a**) Dr = 30%, Fl = 24 mm; (**b**) Dr = 30%, Fl = 48 mm; (**c**) Dr = 50%, Fl = 24 mm; (**d**) Dr = 50%, Fl = 48 mm. * In macromesh fiber-reinforced soils, the highest ultimate bearing capacity (q\({}_{u}\)) was determined as 680 kPa in the case of adding macromesh fiber to the sand at Dr = 50%, Fc = 2%, Fl = 48 mm, and 3B reinforcement depth. The highest BCR was determined as 10.4 by adding macromesh fiber to sand at Dr = 30%, Fc = 2%, Fl = 48 mm, 3B reinforcement depth. * When the reinforcement depth was changed from B to 2B and from 2B to 3B for all fiber lengths and percentages at Dr = 30%, the BCR increased by 69-101% and 28-33%, respectively.