## 4 Results  
### Rockfall Analysis  
Three-dimensional rockfall analyses were performed using RocPro3D (RocPro3D, 2014) three-dimensional rockfall analysis software. RocPro3D is a professional 3D stochastic trajectometric simulation software. This approach (Monte-Carlo type) offers the choice between Gaussian or equiprobable variables for the properties of soils and blocks (initial starting conditions, initial position, mass, rebound perturbations). Thanks to this software, data such as the energy, jump height, etc., of a rock block that starts moving at a certain speed and has a certain mass at a certain point are obtained. Impact energy transfer and dissipation are calculated directly by this program and the results are presented visually. Within the scope of this study, both the blocks that were found around the source rock and the blocks spread on the slope were examined, and the block geometry, maximum block size, and spreading areas were determined. As a result of field observations, it was understood that the block shape is generally spherical and that these blocks reached to the base of the slope. The most important reason for this situation is the weathering pattern seen in volcanic rocks. The exfoliation structures seen in the rocks due to weathering caused the rocks to take a spherical shape. In the rockfall software used in this study, the block shape cannot be defined. The only input parameters are the position, mass, and initial velocity of the block. The output parameters are velocity, height, and path. For this reason, it is thought that the software used fully reflects the field conditions selected within this study. During field studies, the locations of the blocks that traveled the longest distance and the shapes of these blocks were determined. It was observed that the angular blocks did not reach the gabion wall design line and the round blocks traveled the furthest distance. Considering this situation, a rockfall analysis model was established in the study. Such a scenario has not been encountered in the field. Because the distance between the source rock and the planned gabion is long, the blocks move separately at that distance, even if there is more than one rockfall event. Blocks with a mass of 10 tons were dropped along a line from the highest point of the source rock, taking into account the worst-case scenario in the three-dimensional rockfall analyses. Fifty blocks were modeled in each region. In RocPro3D software, different geological units can be defined on the three-dimensional numeric surface model to model the rockfall and different return coefficients (Rn and Rt), and friction coefficients can be assigned for these units. In the study area, a single geological unit has been distinguished based on field observations in the region where the rockfalls occurred. The normal coefficient of restitution (Rn) was accepted as 0.75, the coefficient of tangential restitution (Rt) as 0.75, and the coefficient of friction (k) as 0.4. Cover thickness (less than 50 cm) and dacites outcropping in many areas, as well as the literature data, were taken into account. Rolling lines, jump heights, velocities, and energy values obtained from three-dimensional rockfall  
Figure 10: Digital elevation model created in RocPro3D software (version 6.2). analyses are given in Figures 11 and 12. When the analyses were examined, it was seen that the jump heights for a 10-ton block exceeded 2 m on the steep cliffs at the top, 1 m on average along the slope, and only turned into a rolling shape at the lowest elevations (the areas where the gabion design is planned). However, jump heights of 3 m were recorded in some parts of the lower elevations. At these points, the energy amounts vary between 4000-8000 kJ for a 10-ton block, and the average speed reaches 30 m/s. All risks that may arise from free blocks on the slope are blocked by the farthest gabion design from the source rock. However, in this case, the most effective solution is a gabion wall, as the distance will increase.