نوع مقاله : مقاله پژوهشی
نویسندگان
1 کارشناسی‌ارشد مهندسی تونل و فضاهای زیرزمینی، دانشکده مهندسی معدن، دانشگاه صنعتی امیرکبیر (پلی‌تکنیک تهران)
2 عضو هیأت علمی دانشکده مهندسی معدن-دانشگاه صنعتی امیرکبیر
3 عضو هیات علمی دانشگاه صنعتی امیر کبیر
چکیده
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Summary
Due to the complexity of the tunnel network design in underground mines, there are usually different types of intersection in these mines that their stability is very important.
Introduction
In this research, the stability of one of the bifurcated intersections in Parvadeh Tabas coal mine, which was created by the intersection of slope2 tunnel and access tunnel to maingate5, had been investigated.
Methodology and Approaches
For this purpose, the distribution of induced stresses, the intensity of stress concentration, and the extent of the plastic zone had been investigated using the finite difference numerical method in the FLAC3D software environment.
Results and Conclusions
Based on the results, in the area between the slope tunnel and the access tunnel, the maximum vertical induced stress equal to 25.5 MPa has occurred on the left side of the bifurcation. Also, based on the stress concentration contours in the area between the slope tunnel and the access tunnel, on the left side of the bifurcation, the stress concentration was increased to 1.65 near the slope tunnel, and to 1.71 near the access tunnel. Moving away from the intersection at the roof of the access tunnel, the stress level increases, which can be due to its non-circular and wide cross-section. Based on the shear stresses curve, the concentration of shear stress is higher at the left rock pillar. The maximum amount of shear stress in the left and right corners of the bifurcation is equal to 7.98 and 7.11 MPa, respectively. Due to the existence of rock strata with different strengths, the plastic zone at different distances from the intersection is almost asymmetric, and the presence of the coal seam at the bottom leads to the intensification of the plastic zone, and consequently the instability of the bottom and its uplift.
کلیدواژه‌ها [English]
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