In this study, a parametric study was conducted using FLAC3D numerical models to examine the impact of oblique loading, generated from seam dip, on the strength and the failure propagation pattern of a stone pillar using two simplified geometry types. In type 1, the sidewalls of the pillars were assumed to be perpendicular to the roof and the floor, while in type 2, the sidewalls of pillars were assumed to be vertical. The complex pillar geometry in dipping mines was frequently modeled using these two geometries. To capture a complete picture of the effect of seam dip on pillar stability, the modeled width-to-height (W/H) ratio of the pillars, in situ stress field, and pillars roof/floor interfaces were systematically varied to account for the potential distribution of values for these parameters across the underground stone mines in USA. Results from the numerical modeling indicate that dipping pillars have reduced strength compared with horizontal pillars. Also, an asymmetric failure propagation pattern could be obtained depending on an interaction between the W/H ratio, seam dip, in situ stresses, and pillar geometry.

在这项研究中，使用FLAC3D数值模型进行了参数研究，以使用两种简化的几何类型来检查接缝浸入所产生的斜向载荷对石柱的强度和破坏传播模式的影响。在类型1中，假定支柱的侧壁垂直于屋顶和地板，而在类型2中，假定支柱的侧壁垂直。经常使用这两个几何模型对浸入式矿井中的复杂支柱几何模型进行建模。为了完整地了解接缝倾角对立柱稳定性的影响，系统地改变了立柱的建模宽高比，原位应力场和立柱顶板/底板界面，以说明这些参数在美国地下石材矿山中的潜在分布。数值模型的结果表明，与水平立柱相比，浸渍立柱的强度有所降低。同样，根据W / H比，接缝倾角，原位应力和立柱几何形状之间的相互作用，可以获得不对称的失效传播模式。