非对称应力场临空巷分区域动载响应特征及控制研究

Gob-side roadway is the main area of rockburst occurrence in coal mines. Unlike the roadway in coal seam, the stress field of gob-side roadway is of evident asymmetry. Under the combined action of asymmetric stress field and dynamic load around gob-side roadway, the surrounding rock of gob-side roadway shows the characteristics of asymmetrical fracturing and deformation. Due to the lack of deep understanding, the current control method of the surrounding rock of gob-side roadway is of poor suitability. For this reason, similarity simulation experiment with coupled dynamic and static loading and numerical simulation will be carried out to investigate the characteristics of regionalized response of gob-side roadway under cyclic dynamic loading in the asymmetric stress field, and the ‘traction of seismic wave and reduction of dynamic load’ mechanism of adjacent goaf, to propose and validate control schemes which are applicable to the characteristics of regionalized deformation of gob-side roadway. The proposal mainly involves studying the control mechanism of impact angle and position of dynamic load and barrier pillar size (asymmetric stress field) to the characteristics of regionalized fracturing of gob-side roadway and the ‘traction of seismic wave and reduction of dynamic load’ mechanism of adjacent goaf. The research results can be used to guide the control of gob-side roadway deformation under dynamic loading and rockburst prevention in gob-side roadways.

临空巷是煤矿生产中冲击地压灾害的主要发生区域。与实体煤巷道不同，临空巷的应力场具有明显的非对称性。在非对称应力场和动载的复合作用下，临空巷围岩表现出分区域非对称破裂变形的特点。由于对此缺乏深入的认识，目前的临空巷围岩控制方法的适用性较差。基于此，本申请拟采用动静组合加载相似模拟试验和数值模拟相结合的方法，研究非对称应力场中临空巷围岩在循环动载冲击作用下分区域动态破坏响应特征，以及已回采工作面采空区对临空巷的“震动导引降载”作用机制，提出与临空巷围岩分区域动载变形特征相适应的控制方案，并进行控制方案有效性的验证。该申请主要研究内容包括动载冲击角度、动载冲击位置和煤柱尺寸（非对称应力场）对临空巷围岩分区域动载破坏特征和采空区“震动导引降载”作用的控制机制。研究结果可以用于指导临空巷围岩动载变形控制和冲击防治工作。

煤矿井下巷道受矿山压力静载荷和矿震动载荷的共同作用，其稳定性取决于动静载荷的耦合作用。煤柱的存在造成巷道围岩应力分布和围岩结构的差异性，外加矿震动载相对煤柱的位置特征，使巷道围岩的动载响应呈现出明显的区域差异性特征。在巷道支护设计时，应体现出这一区域差异性特征。.项目研究了不同煤柱宽度条件下巷道围岩对巷道两侧矿震动载的响应特征。针对煤矿现场具体条件，设计了临空巷和实体煤巷道的差异化支护方案，提出了一种巷道支护抗震能力评估方法。基于现场统计的矿震传播特征，对临空巷和实体煤巷的支护方案的抗震能力进行了评估，结果表明差异化支护设计实现了临空巷和实体煤巷抗震能力的均衡匹配。.项目研究成果在新疆托克逊县雨田煤矿、内蒙古鄂尔多斯市红庆河煤矿、山东新汶孙村煤矿、山东菏泽彭庄煤矿和郭屯煤矿、孟加拉国巴拉普库利亚煤矿等进行了应用，对巷道支护稳定性和抗震能力进行了分析评估，并优化了部分矿井的巷道支护设计，为矿井安全生产提供了保障。