It is very important to study the stability of tunnel in area affected by mining activities. In particular, choice coal pillar size has a direct influence on these tunnels. The authors this used Flac3D program model face LC1 with various sizes. 220 m-long known as 20 degrees rock mass layers. studied pillars are widths at 5 m, 8 10 15 and 30 m. highest vertical stress maximum horizontal placed ...

Excavating tunnels in sandy cobble strata carries a high risk of ground collapse caused by instability the tunnel face. In order to prevent at face during excavation, this paper focuses on studying effects various pre-reinforcement method stability sand-cobble strata. Firstly, projects suitable for these are proposed. Then, using FLAC3D established numerical models, then simulate excavation pro...

Bone defects caused by femoral and tibial tunnel enlargement can pose a significant technical challenge when planning to perform revision anterior cruciate ligament reconstruction. A number of options have been described for managing osseous deficiencies, including the use of large autograft or allograft bone dowels to provide sufficient tunnel fill and subsequent structural support for revisio...