摘要
为了研究浅埋间隔式采空区隔离煤柱稳定性及覆岩失稳特征,防止下煤层开采过程中发生动压致灾事故,采用相似模拟实验、理论分析和数值模拟等研究手段对南梁煤矿20109工作面间隔采空区覆岩结构及失稳特征进行研究。结果表明:采空区临时煤柱蠕变失稳诱发基本顶产生回转断裂;采空区上方应力拱相互叠加,采动裂隙并未随着基本顶的破断同步发育至地表,采空区上覆岩层形成"梯形-半圆拱"状垮落带;基本顶断裂形成"W型砌体梁"铰接结构。隔离煤柱两侧断裂岩块形成"双拱桥"式承载结构,煤柱上方形成倒梯形载荷体,论文划分了间隔式采空区覆岩低应力降低区及高应力集中区,建立了间隔式采空区"W型砌体梁+双拱桥"式承载结构模型,并得到数值模拟的验证。
In order to study the stability of isolated coal pillar and overburden instability in shallow-buried interval gob so as to prevent the accidents induced by dynamic pressure in the secondary caving, the overburden structure and instability characteristics of an interval gob behind working face 20109 of Nanliang Coalmine have been studied through similar simulation experiment, theoretical analysis, and numerical simulation. The results have shown that the creep instability from the temporary coal pillar induces the rotary fracture of main roof. The stress arches above the gob are superimposed. The mining-induced fractures do not develop to the surface at the same time of the key strata breaking, and the strata overlying the gob forms into a "trapezoid-semicircular arch" collapse zone. Meanwhile, the main roof forms into a "W-typed masonry beam" bearing structure. The fractured rock block on both sides of the isolated coal pillar constitutes a "double arch bridge" structure, moreover an inverted trapezoidal load is formed above the coal pillar. The low stress decreasing area and high stress concentration area of overburden strata in interval gob are identified. A "W-typed masonry beam + double arch bridge"-type bearing structure model is established in the interval gob, and further verified by numerical simulation.
作者
张杰
王斌
ZHANG Jie;WANG Bin(College of Energy Science and Engineering,Xi'an University of Science and Technology,Xi'an,Shaanxi 710054,China;Key Laboratory of Western Mine Exploration and Hazard Prevention of the Ministry of Education,Xi'an,Shaanxi 710054,China)
出处
《采矿与安全工程学报》
EI
CSCD
北大核心
2020年第5期936-942,共7页
Journal of Mining & Safety Engineering
基金
国家自然科学基金项目(51774229)
陕西省创新能力支撑计划(科技创新团队)项目(2018TD-038)
陕西省自然科学基础研究计划-联合基金项目(2019JLM-41)
煤炭开采水资源保护与利用国家重点实验室开放基金项目(SHJT-17-42.3)。
关键词
浅埋煤层
间隔式采空区
煤柱稳定性
覆岩结构
shallow seam
interval mining gob
coal pillar stability
overburden structure
