Engineering geology of the Arsin-Trabzon section of Trabzon south expressway possible route

SUMMARY Engineering Geology of the Arsin-Trabzon Section of Trabzon South Expressway Possible Route In this study, engineering properties of the rocks and soil outcropping in the Arsin- Trabzon section of the possible route of the south expressway, Trabzon were investigated by means of both field and laboratory studies. For this purpose,this route was mapped geologically with a scale of 1/25.000 initialy and afterwords, engineering geogical map with a scale of 1/10.000 based on weathering grades was prepared. Six different units were distinguished. These are from down to top are rhyolithe- rhyodacite and dacite (Upper Cretaceous-Paloecen), alternation of limestone, marl, sandstone and tuff (Upper Cretaceous-Paloecen), andesite-basalt and pyroclastic rocks (Eocen), poligenetic-heterogen conglomerate and breccia (Pliocen), terrace and alluvium (Quternary). Six units which were distinguished in engineering geology map were considered seperately from the point of engineering properties, and possible geotechnical properties for each unit were examined. These units which are rock are limestone, rhyodacite, rhyolitic breccia and conglomerate-breccia. Limestone and rhyodacite are good gualified, middly-fractured, middle-upto wide spaced, slightly and middry roughly, partly weathered and hydrotermaly altered as well middle strength rock. Rock mass rating of these units were carried out and studied in terms of being tunnel, foundation and slope rock. Accordingly, it is concluded that limestone and rhyodacite are suitable for tunnel and foundation rock and not suitable for slope rock. The other rock units turned out to be poor quality in terms of engineering properties because of their highly weathered nature and poor cementation Two different soil types were distinguished based on their clay mineralogy. These soil types have high placticity. Slope, aspect and heigth value maps of the study route were produced by GIS technique, for Risk map was made for possible mass movement by overlay processes of slope map and engineering geology map., Areas with risk and without risk were thereby distinguished. In addition to this, 3D digital elevetaion model for the study area was produced. Keywords: Expressway, Geotechnical, GIS. IX