【作者】 张连贵；

【导师】 高井祥；

【作者基本信息】 中国矿业大学 ， 大地测量学与测量工程， 2009， 博士

【摘要】 随着矿井开采日益深部化,非充分开采地表沉陷问题越来越突出,有必要对非充分开采覆岩破坏机理与地表沉陷规律进行研究。本文针对兖州矿区的地质采矿条件,通过对现场实测资料分析、相似材料模拟试验、离散元数值模拟计算及物理勘探等多种研究手段,对兖州矿区非充分开采覆岩破坏机理与地表沉陷规律进行了系统的分析研究。通过对兖州矿区非充分开采地表移动观测站的实测数据进行分析总结,得出:(1)开采沉陷充分程度随着连续开采工作面个数的增加而增大,由非充分变为充分的沉陷状态。薄冲积层下采用宽深比,厚冲积层下按采宽与基岩厚度之比来评价采动程度。(2)非充分开采下沉率随采动程度的变化而呈现“缓慢增加→急剧增加→缓慢增加→稳定”的分段变化的规律。(3)厚冲积层条件下深部开采地表下沉率公式4)非充分开采地表移动预计,可沿用概率积分模型并通过修改预计参数来实现。下沉率和拐点偏移距受采动程度影响较大。随开采程度的增加,拐点偏移方向从煤柱一侧向采空区一侧移动,拐点偏移距由外偏最大逐渐变小,到内偏增大至内偏最大。通过相似材料模拟试验及数值计算,揭示了非充分开采覆岩破坏机理和厚冲积层条件下采动程度衡量方法,得出:(1)极不充分开采阶段,上覆岩层形成较小压力拱,岩层垮落范围小,移动不充分,地表移动量很小。(2)厚冲积层条件下的采动程度不能沿用宽深比指标,应对冲积层厚度、基岩厚度及其比例关系予以考虑。通过数值模拟对煤柱稳定性进行分析,得出:工作面间的隔离煤柱的宽度和强度对煤柱稳定性有决定性影响,对地表沉降量有一定影响。当煤柱尺寸较小时,煤柱易失稳,出现冲击地压现象。应用非充分开采地表沉陷规律研究成果,对兖州矿区鲍店煤矿泗河下压煤、南屯煤矿高压线下压煤等进行了开采实践,取得了良好的经济效益和社会效益。更多还原

【Abstract】 With the development of deep mining, sub-critical excavation problems are becoming increasingly prominent, and it is very necessary to study overburden failure mechanism and surface subsidence law of sub-critical excavation completely. Based on actual geology and mining conditions of Yanzhou Mining Area, field measured data analysis, many research methods were employed, such as, similar material simulation test, discrete element numerical simulation and physical detection, so that overburden failure mechanism and surface subsidence law of sub-critical excavation were analyzed and studied completely.Measured data of surface movement observation station due to sub-critical extraction in Yanzhou mining area were analyzed and summed up, some conclusions are as follows: (1) as the numbers of working faces increased, surface mining degree aggravated, mainly from sub-critical excavation to full mining. (2) surface subsidence ratio changes piecewise with mining degree changes, and appears the laws of‘gently increase→suddenly increase→slowly increase→stability’. Given thin alluvium, mining degree is determined in term of mining width rate to mining deep, while thick alluvium, in term of mining width rate to the bedrock height. (3) Surface subsidence ratio formula under large mining deep and thick alluvium is (4) The probability integral method was employed to predict sub-critical excavation only if strata movement parameters were modified. As mining degree increases, inflection point deviation direction change from coal pillar side to gob side, while, deviation of inflection point become smaller from maximum outside deviation value, ultimately become maximum inside deviation value.Similar material and numerical simulation tests were employed to study strata movement mechanism of sub-critical excavation, and determine the judging method of mining degree under thick alluvium. The results show that, (1) overlying strata form smaller pressure arc, the caved zone smaller, strata movement not sufficient, and surface movement values very small. (2) Mining degree can’t use the index of mining width rate to mining deep, and should wholly consider the alluvium height, bedrock height and proportional relationship under the condition of thick alluvium.Coal pillar stability was analyzed by numerical simulation method. The results show that the width and strength of isolated coal pillars among working faces have a decisive influence on coal pillar stability, and a certain impact on surface subsidence value. When small sizes, coal pillars easily lose stable, and take up rock burst.Above laws are applied to Yanzhou mining area. Mining reserves under Sihe River (Baodian coal mine) and high voltage line (Nantun coal mine) has great economic and social benefits. Applications prove the research results of paper are correct and reasonable.更多还原