One of the most common critical areas of longwall mining in terms of ground stability are the gateroad and bleeder entries. These critical entries provide much-needed safe access for miners and allow for adequate ventilation required for dilution of hazardous airborne contaminants and must remain open during mining of a multi-panel district. This paper is focused on the stability of the longwall entries subjected to a single abutment load such as bleeders, first tailgate, and last headgate. First tailgate and last headgate are also referred to as blind headgate and tailgate. A study of a longwall district through conditions mapping, support evaluations, and numerical modeling was conducted and evaluated by researchers from the National Institute for Occupational Safety and Health (NIOSH). The condition mapping and support evaluations were performed on entries that spanned the previous five years of mining and relied on a diverse selection of supports to maintain the functionality of the entry. Numerical modeling was also conducted to evaluate various support types with further investigation and comparison to the condition mapping. The study demonstrated the importance of the abutment load decay versus distance from the gob edge, the potential for a reduction in material handling related injuries, as well as optimal usage of secondary and standing support.

就地面稳定性而言，长壁开采最常见的关键领域之一是闸道和泄放通道。这些关键入口为矿工提供了急需的安全通道，并允许稀释有害的空气传播污染物所需的足够通风，并且在开采多面板区域期间必须保持开放状态。本文的重点是承受单个桥台载荷（例如泄放器，第一个后挡板和最后一个后挡板）的长壁入口的稳定性。第一个后挡板和最后一个后挡板也称为盲门和后挡板。美国国家职业安全与卫生研究所（NIOSH）的研究人员通过条件映射，支持评估和数值建模对长壁区进行了研究。在过去五年的开采过程中，对条目进行了条件映射和支持评估，并依赖各种支持来维护条目的功能。还进行了数值建模，以评估各种支撑类型，并进行进一步调查并与条件映射进行比较。该研究表明，基台负载衰减与距料滴边缘的距离的重要性，减少与物料搬运相关的伤害的潜力以及最佳使用辅助支撑和站立支撑的重要性。还进行了数值建模，以评估各种支撑类型，并进行进一步调查并与条件映射进行比较。该研究表明，基台负载衰减与距料滴边缘的距离的重要性，减少与物料搬运相关的伤害的潜力以及最佳使用辅助支撑和站立支撑的重要性。还进行了数值建模，以评估各种支撑类型，并进行进一步调查并与条件映射进行比较。该研究证明了基台负载衰减与距料滴边缘的距离的重要性，减少与物料搬运相关的伤害的潜力以及最佳使用辅助支撑和站立支撑的重要性。