KONİK YAYILIM YAKLAŞIMIYLA KAYA DÜŞMESİ POTANSİYELİNİN DEĞERLENDİRİLMESİNE YÖNELİK BİR YÖNTEM ÖNERİSİ

Abstract

Rockfall is a phenomenon that frequently occurs in the mountainous areas and threats vital elements such as settlements, highways, infrastructures etc. Deterministic and probabilistic rockfall analyses are effective in small areas such as railways and highways. However, due to the limitations and difficulties of these analyzes, the interest to empirical approaches using for preparation of rockfall maps of large areas, especially at the regional scale, has been increased. For the regional scale, the cone propagation approach is a practical method that only uses source area map and digital elevation model as the input parameters. The cone propagation method uses DEM for determining possible propagation zone based on simple geometric rules known as energy line angle (reach angle) and shadow angle. Energy line angle depends on various parameters such as block shape, roundness, litholology, topography, the friction between block and slope and coefficients of restitution. Therefore, development of an effective method considering geological and morphological features in determining energy line angle constitutes basis for this thesis. For this purpose, a maximum run-out score (MMP) rating was proposed for determining of maximum reach angle iv (EÇAmax_stop). In addition, several graphs were prepared at which the energy line angles can be predicted for very low, low, medium, high and very high susceptibility classes to prepare the susceptibility maps which is a measure of being affected by rockfall potential. The final stage, a Rockfall Hazard Rating (RHR) method was presented. Three different alternatives for topography were taken into account to reveal topographical effects in the rockfall hazard rating method for this study. The method was applied in Kargabedir and Sivrihisar pilot areas. It was revealed that topographical correction based on the elevation which method, developed in this study, represented the most realistic results.