厚松散含水层薄基岩采场荷载传递与压架机理研究

发布时间：2018-06-13 05:29

本文选题：厚松散含水层 + 薄基岩采场　；参考：《安徽理工大学》2017年硕士论文

【摘要】：近年来,我国华东地区发生了数十起松散含水层下薄基岩工作面采煤时导致压架致灾的事故,并且此类综采工作面压架事故呈现增多的趋势,造成了重大的经济损失,严重威胁了煤矿企业的安全生产,这一情况引起了行业领导和众多学者的关注。松散含水层下薄基岩采场开采时常伴随有顶板压力显现异常增大导致工作面压架,并且随工作面推进时常呈周期性突水,因此,针对此类情况,本文采用相似模拟、理论分析和现场对比实测的方式对含水层下薄基岩采场特殊的覆岩结构及其压架机理进行了研究。根据相似模拟实验结果建立了支架-围岩力学计算式,分析了含水层载荷传递作用对不同关键层组合条件下的覆岩破断机制的影响,研究结果表明:(1)含水层对薄基岩中仅赋存有单一关键层的工作面影响要大于对多关键层的影响。单一关键层在承受关键层自重及其与含水层之间垮落岩层载荷的同时,还要承受来自承压含水层的水压力及其传递的上覆巨厚冲积层的荷载,这就导致单一关键层无法形成具有稳定支撑能力的"砌体梁"结构,更容易发生滑落失稳,进而造成工作面压架;(2)含水层下两关键层间距大小将直接影响下位关键层破断形成"砌体梁"结构的稳定性:①间距较小两关键层在含水层作用下容易产生复合破断,其破断特征与单关键层相似,下位关键层将不能形成稳定的"砌体梁"结构;②两关键层间距足够大的条件下,下位关键层破断后形成的"砌体梁"结构将受到上位关键层随下方岩体跨落后形成的"自然平衡拱"的保护,"阻断"上位关键层上方松散层和含水层水压力向"砌体梁"的施加,这样"砌体梁"就不易因为承受过大的载荷而滑落失稳,工作面也就不容易压架。文章最后以顾北矿1202(3)综采工作面(含水层下单一关键层)和潘二矿1811(1)综采工作面(含水层下双关键层)为工程背景,通过对比和分析实际开采过程中的矿压显现特征,进一步验证含水层载荷传递作用对不同的关键层组合将对工作面支架承受的荷载产生不同的影响。其研究结果为类似地质条件下的煤矿工作面实现安全高效开采提供了一定的理论依据。
[Abstract]:In recent years, there have been dozens of accidents in East China, which resulted in the collapse of the frame when mining the thin bedrock face under the loose aquifer, and this type of fully mechanized mining face has a tendency to increase, resulting in significant economic losses. Serious threat to the safety of coal mining enterprises, this situation has attracted the attention of industry leaders and many scholars. The mining of thin bedrock under loose aquifer is often accompanied by the abnormal increase of roof pressure, which leads to the pressure frame of the face, and it often takes on periodic water inrush with the advance of the working face. Therefore, in this paper, similar simulation is used for this kind of situation. The special overburden structure and pressure frame mechanism of thin bedrock stope under aquifer are studied by theoretical analysis and field comparison. Based on the results of similar simulation experiments, the mechanical calculation formula of brace-surrounding rock is established, and the influence of aquifer load transfer on the failure mechanism of overburden rock under different combination conditions of key layers is analyzed. The results show that the influence of the aquifer on the face with only one critical layer in the thin bedrock is greater than on the multi-critical layer. A single critical layer not only bears the load of the dead weight of the critical layer and the falling rock between the aquifer and the aquifer, but also bears the load of the water pressure from the confined aquifer and the overlying thick alluvial layer. As a result, a single critical layer can not form a "masonry beam" structure with stable supporting capacity, and it is more likely to slip and lose stability. Thus, the size of the distance between the two key layers under the aquifer will directly affect the stability of the "masonry beam" structure caused by the breakdown of the two key layers under the aquifer. Its fracture characteristics are similar to those of single critical layer, and the lower critical layer will not be able to form a stable "masonry beam" structure with sufficient spacing between the two critical layers. The "masonry beam" structure formed after the breakdown of the lower key layer will be protected by the "natural equilibrium arch" formed by the upper key layer along with the lag of the lower rock mass span, and "block" the "water pressure direction of the loose layer and aquifer above the upper key layer." The application of masonry beams, Thus, masonry beams are not easy to slip and lose stability because of excessive load, and the face is not easy to press the frame. Finally, taking the fully mechanized mining face (single key layer under aquifer) and the fully mechanized mining face (double key layer under aquifer) in Gubei Mine as engineering background, the paper compares and analyzes the characteristics of rock pressure behavior in actual mining process by taking the fully mechanized coal face (single key layer under aquifer) and 1811111 fully mechanized mining face (double key layer under aquifer) as engineering background. It is further verified that the load transfer of aquifer will have different effects on the load bearing by the working face support with different key layer combinations. The results provide a theoretical basis for the safe and efficient mining of coal face under similar geological conditions.
【学位授予单位】：安徽理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD323

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