The present research work aims to determine the stability of a rectangular tunnel excavated in rock masses obeying Hoek-Brown yield criteria under steady-state groundwater flow using lower bound limit analysis. During tunneling in presence of groundwater table seepage forces are generated which causes a decrease in stability of rock mass. The total head distribution due to seepage is obtained by using 2D finite element software OPTUM G2. The stability has been presented by a non-dimensional number σ_ci/γ_max^′H obtained for various combinations of B/h, H/h, H_w/h, σ_ci/γ_wh, m_i, GSI and D where B and h are width and height of the tunnel, respectively, H is the depth of tunnel from ground surface and H_w is height of groundwater table from the tunnel roof, respectively, σ_ci and γ^′ are uniaxial compressive strength and submerged unit weight of rock, respectively, γ_w is unit weight of water and m_i, GSI and D are Hoek-Brown parameters.

中文翻译：

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稳态地下水流下霍克-布朗岩体中矩形隧道的稳定性

本研究工作旨在通过使用下限分析来确定在稳态地下水流下遵循Hoek-Brown屈服准则的岩体中开挖的矩形隧道的稳定性。在存在地下水位的隧道中，会产生渗透力，从而导致岩体稳定性降低。通过使用2D有限元软件OPTUM G2获得由于渗漏引起的总水头分布。稳定性已经呈现由无量纲数σ _CI / γ_最大^' ħ为的各种组合获得的乙/ H，H / H，H ^_瓦特/小时，σ _CI / γ_瓦特H，M_我，GSI和d，其中乙和ħ是宽度和隧道的高度，分别ħ是隧道的地面表面和深度ħ_瓦特是地下水位高度从隧道屋顶分别σ _CI和γ ^'是单轴抗压强度和岩石的浸没单位重量分别γ_瓦特是水单位重量和中号_我，GSI和d是霍克-布朗参数。