保护层开采被保护层膨胀变形分析方法

基于传统的膨胀变形特征分析多是对被保护层在法线方向上通过测量两个定点 的距离变化来表征，这种从“两个定点”距离变化角度分析膨胀变形的方法只考虑被保 护层在法线方向上的变形特征，不能反应出被保护层的横向变形。针对计算结果不能全 面、准确的反应煤岩体的膨胀变形特征问题，首次提出了保护层开采过程中被保护层膨 胀变形的“四个定点围域面积”分析方法，该方法通过面积膨胀变化分析被保护层膨胀 变形特征。研究分析了在开采实践和实验室中“四个定点围域面积”的监测方案、面积 分析计算方法和“四个定点围域面积”的合理尺度。以沙曲矿多煤层开采相似模拟为背 景，分析了不同尺度下“四个定点围域面积”分析法的精度。研究表明，“四个定点围 域面积”分析方法较“两个定点”分析方法精度更高，被保护层厚度1倍尺度围域内划 分的面积单元格越多，膨胀变形计算精度越高。

Analysis method on swelling deformation of protected seam in the process of protective coal seam exploitation

Based on the traditional feature analysis of swelling deformation, the swelling deformation of protected seam is mostly represented by measuring the distance change of two fixed points in the normal direction of protected seam, which only considers the deformation feature of protected seam in the normal direction, while can not reflect the lateral deformation of protected seam. Aiming at the problem that the calculation results can not reflect the swelling deformation feature of coal and rock body comprehensively and accurately, an analysis method of "four fixed points enclosed area" on swelling deformation of protected seam in the process of protective coal seam exploitation was proposed for the first time, which analyzed the swelling deformation feature of protected seam through the area swelling change analysis. The monitoring scheme, the analysis and calculation method of area and the reasonable scale of "four fixed points enclosed area" were put forward in the engineering practice and laboratory. Taking the similar simulation of multi coal seam mining in Shaqu mine as background, the accuracy of "four fixed points enclosed area" analysis method under different scales were analyzed. The results showed that it has higher accuracy than the "two fixed point" analysis method. The more area cells divided in the enclosed region with 1 times scale of protected seam thickness, the higher the calculation accuracy of swelling deformation.