Evaluation of rockfall hazard based on UAV technology and 3D Rockfall Simulations

Abstract

Hacıabdullah village, where rockfall events occur frequently, is an important mountainous region located within the boundaries of Niğde province, which is one of the top provinces in Türkiye in terms of rockfall events and is located in the Central Anatolia Region. Despite the frequent occurrence of many rockfall events of varying sizes, no precautions are taken as a result of these events, leading to economic damages. Therefore, Hacıabdullah village, which poses a high danger and risk in terms of slope instability and rockfall potential, has been selected as the study area. The study aims to evaluate rockfall events occurring on steep slopes in Haciabullah village, based on the potential rock blocks that could fall, by modeling them according to their geometries. Within this scope, the potential 17 rock blocks that could fall have been identified in the field and modelled using RAMMS 3D rockfall software according to their geometric characteristics. In addition to the geometric characteristics of the rock blocks, their potential falling areas, velocities, jump heights, and kinetic energies will also be determined, the basis of the rockfall hazard analysis. For the 3D modeling of the study, UAV-DSM (3cm resolution), which represents the high-resolution surface of the topography, has been used as the main dataset. As a result of 3D rockfall modeling, the maximum kinetic energy, maximum velocity, and maximum jump height of the falling blocks reached 3476 kJ, 23.1 m/s, and 14.57 m, respectively. The result of the kinematic analysis showed a higher probability of toppling type in the whole study area. Rocks that do not move very far from the source area are; in other words and may significantly damage the roads. However, rolling blocks, in other words, blocks that can travel long distances from the source area, have the potential to cause great damage to the settlement areas, roads, and trees. According to the hazard map, blocks involve high and moderate levels of risk for settlement units.