Stability Investigations of Rock Slopes in the Sumela Monastery (Maçka-Trabzon, Northeastern Turkey)

The Sumela Monastery was established on a cliff at the foots of Karadağ dominating Altındere valley in the county of Maçka in Trabzon, northeastern Turkey. With its great historical and touristic importance, the monastery is visited by approximately 180.000 local and foreign tourists every year. Mass movement on form rock fall occurred in 2001 on the south slope and some social facilities of the monastery and communication roads were damaged. The geological and geotechnical characteristics of the rock slope were investigated and rock fall hazard analyzed. In the rock samples obtained from the study area, uniaxial compressive strength and point load strength were calculated in the laboratory and, by using the scanline survey method in the site, discontinuity and rock mass characteristics were determined. In situ compressional wave velocities were determined by using the seismic refraction method and ultrasonic wave velocities were measured in laboratory on the rock samples. Rock classifications were made, which helped to find the weathering degree, Q index, Rock Quality Designation (RQD) values and Rock Mass Rating System (RMR) values for the Sumela Monastery rock slope.