Ljubojev M.,Minig and Metallurgy Institute |
Popovic R.,Minig and Metallurgy Institute |
Avdic M.,University of Tuzla |
Ignjatovic L.D.,Minig and Metallurgy Institute |
Ljubojev V.,Minig and Metallurgy Institute
Technics Technologies Education Management | Year: 2010
The paper presents experimental contribution to defining the legality of strength gray sandstone with the route of the tunnel "Krivelj's river", examined in the complex state of stress. Experience has shown, and experiments confirm, that all materials and rocks have a limited ability of accumulation mechanical energy, or to oppose unlimited deformations. In isothermal loading process, the two extreme states of all material behavior can be observed. The first is extension, which is based on a material attribute that becomes more plastic. The second is rigidity; changing the materials structure at certain border loads. Testing the legality of gray sandstone strength, from the route of the "Krivelj's river" tunnel, was made on twelve samples with dimensions d x h = 5.4 × 8.1 [cm]. Seven samples were examined in the complex stress condition in s2=s3=2,0; 5,0; 10,0; 20,0; 30,0; 40,0; 55,0 [MPa] and five samples of the σ2=σ3=0.