Excavability properties of rock masses in the water transmission tunnel route of Yoncali dam (Malatya)

Today, the importance of underground projects is ncreasing day by day in parallel with increasing urbanization and related needs such as transportation, energy and water. One of the most important factors affecting cost in such projects is the excavatability of the units to be excavated. Until today, some empirical classifications were proposed by several researchers to determine the excavation classes and excavation method of rock masses. In this study, field and laboratory studies were carried out to determine the excavation classes of basalt, dacite, aglomera, tuff, shale, marl and limestones in the transmission tunnel route of the Yoncalı Dam, which is under construction in Arguvan province of Malatya. The results obtained were evaluated using 17 different empirical excavation classifications and general excavation classes of each rock mass were determined. According to the results of the classifications; basalt, dacite, aglomera, shale, marl and limestones along the tunnel route are in the Medium Hard-Hard-Very Hard excavatability class and it is necessary to excavate these rock masses by blasting. The excavation class of the tuffites is Hard - Very Hard ripping; However, it was determined that there is no need to blast the tuff during excavation.