Naslov
Some engineering properties of limestone : Tunnel Stražina case study (Croatia)

Autori
Toševski, Aleksandar ; Pollak, Davor ; Ženko, Tomislav ; Aljinović, Dunja ; Tadej, Neven

Izvornik
Tunnelling and underground space technology (0886-7798) 26 (2011), 1; 242-251

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, stručni

Ključne riječi
Stražina Tunnel; RMR; transgressive contact; limestones; karstified terrains; overprofile

Sažetak
The paper presents geological and engineering geological characteristics of the Stražina Tunnel along the Bisko-Šestanovac section of the Zagreb-Split-Dubrovnik highway in Croatia. This paper compares the actual conditions of the rock mass during the excavation with a prediction model that preceded the excavation. From the engineering-geological viewpoint the rock mass in the tunnel was of a significantly higher quality than the prediction model. The specific geological feature of the Stražina Tunnel, with its right and left tunnel tube, is the passage of the right tunnel tube through a transgressive contact between Upper Cretaceous rudist limestones and Eocene foraminiferal limestones. Since this is the only tunnel in Croatia excavated through this particular transgressive contact, the geological and engineering properties of the transgression zone were up to now only assumed. Therefore, additional mineralogical, petrographical and engineering geological observations were carried out in order to determine and describe the transgression zone. The results are presented in this paper. In the left tunnel tube the contact between the mentioned litostratigraphic Units is of the fault type. This paper also briefly deals with the significance and cause of the overprofile excavation during tunneling through strongly karstified carbonate rocks. Consequently, special attention was paid to the overprofile during excavation since it can significantly affect tunneling costs.

Izvorni jezik
Engleski

Znanstvena područja
Rudarstvo, nafta i geološko inženjerstvo

POVEZANOST RADA