巨厚关键层破裂运动是诱发矿山动力灾害的重要因素，探究其厚度变化对采动应力分布及破裂动载的影响，对明确巨厚关键层采场动、静载来源及冲击矿压孕育机制具有重要意义，是冲击矿压风险预测及灾害防控的理论基础。以陕西彬长矿区某矿非均厚“弓形”巨厚关键层为研究对象，综合理论分析与数值仿真计算，剖析了巨厚关键层“弓形”形态下伏煤岩体采动应力异常集中的力学原理，探明了“弓形”形态对巨厚关键层破裂特征的影响规律，揭示了“弓形”形态下伏区域动静载叠加致灾机制，据此提出了“弓形”巨厚关键层破裂致灾风险预测方法。结果表明，“弓形”巨厚关键层底部凸起导致下伏煤岩体垂直应力异常集中，相较于均匀厚度巨厚关键层，该区域煤岩体垂直应力额外增加22.1 MPa，增幅比例高达56%，此为下伏煤岩体高静载形成的根本原因。同时，伴随着开采范围的扩大以及非均厚“弓形”巨厚关键层运动，造成其底部内凹拐角区出现显著的高应力集中现象，导致该区域岩石发生破裂及弹性能快速释放，此为强动载形成主要原因。在上述非均厚“弓形”巨厚关键层动静载叠加作用下，煤柱大巷区域极易出现冲击矿压。基于此，准确识别并定位了非均厚“弓形”巨厚关键层影响下采动覆岩动载形成来源及发生区位，结合巨厚关键层分布式光纤原位监测结果，以光纤断裂高度为监测指标，验证了巨厚关键层破裂及动载荷形成之间的内在联系。

The rupture of super-thick key strata is a crucial factor in triggering mine dynamic disasters. Investigating the impact of their non-uniform thickness on mining-induced stress environments and rupture dynamic loads, and further revealing the mechanism of dynamic and static loading on rock burst pressure, is the theoretical foundation for predicting rock burst risks and disaster prevention and control. This paper investigates the non-uniformly thick “bow-shaped” super-thick key strata in the Binchang mining area of Shaanxi. Through comprehensive theoretical analysis and numerical simulation, it analyzes the mechanical principle of abnormal stress concentration in the coal rock mass beneath the “bow-shaped” super-thick key strata, clarifies the influence of the “bow-shaped” morphology on the rupture characteristics of the super-thick key strata and reveals the mechanism of dynamic and static load superposition in the area beneath the “bow-shaped” formation, leading to rock bursts. Based on the study above, a method for predicting the disaster risks caused by the rupture of “bow-shaped” super-thick key strata is proposed. The results show that in the convex area under the “bow-shaped” formation of the super-thick key strata, the high stress is exceptionally concentrated, increasing the coal rock body stress by an additional 22.1 MPa, with an increase rate of up to 56%, which is the fundamental reason for the high static load formation in the underlying coal-rock body. At the same time, the principal stress in the concave area of the “bow-shaped” formation concentrates and undergoes significant deformation, increasing the risk of strong dynamic loads due to rupture. Under the combined action of dynamic and static loads in the non-uniformly thick “bow-shaped” super-thick key strata, the rock bursts are likely to occur in the pillar and roadway areas. The proposed method for predicting the disaster risks due to the rupture of “bow-shaped” super-thick key strata effectively guides the disaster prevention and control in high-risk mining areas prone to rock bursts. Additionally, the distributed fiber optic field measurement results validate the intrinsic connection between the rupture of super-thick key strata and the generation of dynamic loads.