Accurately estimating load distributions and ground responses around underground openings play a significant role in the safety of the operations in underground mines. Adequately designing pillars and other support measures relies highly on the accurate assessment of the loads that will be carried by them, as well as the load-bearing capacities of the supports. There are various methods that can be used to approximate mining-induced loads in stratified rock masses to be used in pillar design. The empirical methods are based on equations derived from large databases of various case studies. They are implemented in government approved design tools and are widely used. There are also analytical and numerical techniques used for more detailed analysis of the induced loads. In this study, two different longwall mines with different panel width-to-depth ratios are analyzed using different methods. The empirical method used in the analysis is the square-decay stress function that uses the abutment angle concept, implemented in pillar design software developed by the National Institute for Occupational Safety and Health (NIOSH). The first numerical method used in the analysis is a displacement-discontinuity (DD) variation of the boundary element method, LaModel, which utilizes the laminated overburden model. The second numerical method used in the analysis is Fast Lagrangian Analysis of Continua (FLAC) with the numerical modeling approach recently developed at West Virginia University which is based on the approach developed by NIOSH. The model includes the 2D slice of a cross-section along the width of the panel with the chain pillar system that also includes the different stratigraphic layers of the overburden. All three methods gave similar results for the shallow mine, both in terms of load percentages and distribution where the variation was more obvious for the deep cover mine. The FLAC3D model was observed to better capture the stress changes observed during the field measurements for both the shallow and deep cover cases. This study allowed us to see the shortcomings of each of these different methods. It was concluded that a numerical model which incorporates the site-specific geology would provide the most precise estimate for complex loading conditions.

准确估算地下洞口周围的载荷分布和地面响应在地下矿井作业的安全中起着重要作用。适当设计支柱和其他支撑措施在很大程度上取决于对它们所承受的载荷以及支撑件的承重能力的准确评估。可以采用多种方法来估算要用于立柱设计的分层岩体中采矿引起的载荷。经验方法是基于从各种案例研究的大型数据库中得出的方程式。它们在政府认可的设计工具中实现，并得到广泛使用。也有分析和数值技术用于更详细地分析感应载荷。在这项研究中，使用不同的方法分析了具有不同面板宽深比的两个不同的长壁矿。分析中使用的经验方法是使用邻接角概念的方衰减应力函数，该函数在美国国家职业安全与健康研究所（NIOSH）开发的支柱设计软件中实现。分析中使用的第一种数值方法是边界元素方法LaModel的位移不连续性（DD）变体，该方法利用了层状覆盖层模型。分析中使用的第二种数值方法是连续西氏快速拉格朗日分析（FLAC），该方法是西弗吉尼亚大学最近开发的数值建模方法，该方法基于NIOSH开发的方法。该模型包括沿着面板宽度的2D切片，带有链柱系统，还包括覆盖层的不同地层。在负荷百分比和分布方面，这三种方法都对浅层矿井产生了相似的结果，而深层矿井的变化更为明显。观察到FLAC3D模型可以更好地捕获在浅层和深层情况下现场测量期间观察到的应力变化。这项研究使我们看到了每种不同方法的缺点。结论是，结合特定地点地质情况的数值模型将为复杂的加载条件提供最精确的估计。在负荷百分比和分布方面，这三种方法都对浅层矿井产生了相似的结果，而深层矿井的变化更为明显。观察到FLAC3D模型可以更好地捕获在浅层和深层情况下现场测量期间观察到的应力变化。这项研究使我们看到了每种不同方法的缺点。结论是，结合特定地点地质情况的数值模型将为复杂的加载条件提供最精确的估计。在负荷百分比和分布方面，这三种方法都对浅层矿井产生了相似的结果，而深层矿井的变化更为明显。观察到FLAC3D模型可以更好地捕获在浅层和深层情况下现场测量期间观察到的应力变化。这项研究使我们看到了每种不同方法的缺点。结论是，结合特定地点地质情况的数值模型将为复杂的加载条件提供最精确的估计。这项研究使我们看到了每种不同方法的缺点。结论是，结合特定地点地质情况的数值模型将为复杂的加载条件提供最精确的估计。这项研究使我们看到了每种不同方法的缺点。结论是，结合特定地点地质情况的数值模型将为复杂的加载条件提供最精确的估计。