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论文中文题名:

 基于双K断裂准则的采场顶板破断机理及控制技术研究    

姓名:

 郑承先    

学号:

 20204228061    

保密级别:

 公开    

论文语种:

 chi    

学科代码:

 085100    

学科名称:

 工学 - 建筑学    

学生类型:

 硕士    

学位级别:

 工程硕士    

学位年度:

 2023    

培养单位:

 西安科技大学    

院系:

 建筑与土木工程学院    

专业:

 建筑与土木工程    

研究方向:

 岩土力学与工程应用    

第一导师姓名:

 李金华    

第一导师单位:

 西安科技大学    

论文提交日期:

 2023-06-12    

论文答辩日期:

 2023-05-31    

论文外文题名:

 Research on stope roof breaking mechanism and control technology based on double K fracture criterion    

论文中文关键词:

 断裂力学 ; 初次来压 ; 周期来压 ; 双K断裂准则 ; 控制技术    

论文外文关键词:

 Fracture mechanics ; initial pressure ; periodic pressure ; double K fracture criterion ; control technique    

论文中文摘要:

如何科学、准确的预测来压步距是有效降低采场事故发生的重要途径,是保障煤矿安全高效生产的重要条件之一。本文通过理论分析、数值模拟及现场监测验证等方法开展研究,对采场矿压显现规律展开深入分析。针对性地提出合理控制措施。主要研究内容如下:

(1)以存在天然裂隙的岩梁为例,利用断裂力学理论确定裂纹扩展因素,结合双K强度参数,把初次来压前后顶板的断裂过程分为微观裂纹扩展阶段、宏观裂缝稳定扩展阶段()、宏观裂纹失稳扩展()、完全破坏阶段,描述了四个阶段的顶板裂纹状态,研究了基于双K断裂准则的采场顶板破断机理。

(2)利用数值模拟软件,分析了初次来压前和初次来压后采场顶板应力和位移的分布,结果表示在初次来压前变形主要集中在跨中,水平和竖向应力越靠近两端越大,说明顶板中部与端部是易破坏位置,易产生主控裂纹。初次来压后水平应力主要集中在工作面上方,即工作面上方易产生主控裂纹。

(3)基于断裂力学理论,考虑了裂纹位置对顶板破断的影响,建立了采场顶板初次来压模型,分析了工作面地质条件下顶板的受力,推导了采场初次来压步距公式;分析了初次来压步距与基本顶断裂韧度、埋置深度、人工裂缝长度及人工裂缝位置等参数的关系。分析结果表明:初次来压步距随断裂韧度的增大而增大;随埋置深度的增大、人工裂缝长度的减小而减小;主控裂缝位置越接近中部或端部,初次来压步距越小,与数值模拟研究结果一致。

(4)根据覆岩协调变形机理,将直接顶与支架作用通过受力传导作用于基本顶,建立自带损伤裂纹的采场顶板周期来压断裂力学模型,推导出直接顶作用下的基本顶周期来压步距公式;分析了基本顶岩石裂缝长度、直接顶厚度等参数对周期来压的作用规律,结果表示基本顶断裂韧度与周期来压近似呈线性关系且不受其他参数影响。

(5)结合陕北某煤矿S1223工作面矿压监测分析,总结出该工作面矿压显现基本规律。根据本文采场顶板初次来压步距断裂力学模型预测了初次来压步距,提出有效的控制措施。根据初次破断距计算了支架工作阻力,确认了支架选型的合理性。通过采场顶板周期来压断裂力学模型理论计算的周期来压步距,与现场结果基本一致。

论文外文摘要:

How to scientifically and accurately predict the weighting interval is an important way to effectively reduce the occurrence of stope accidents and one of the important conditions to ensure the safe and efficient production of coal mines. In this paper, through theoretical analysis, numerical simulation and field monitoring and verification, the law of mine pressure appearance in stope is analyzed in depth. Put forward reasonable control measures. The main research contents are as follows. 

(1)Taking the rock beam with natural cracks as an example, the fracture mechanics theory is used to determine the crack propagation factors. Combined with the double K strength parameters, the fracture process of the roof before and after the initial weighting is divided into micro-crack propagation stage, macro-crack stable propagation stage (), macro-crack instability propagation (), and complete failure stage. The roof crack state of the four stages is described, and the fracture mechanism of the stope roof based on the double K fracture criterion is studied.

(2)Using numerical simulation software, the distribution of stress and displacement of stope roof before and after initial weighting is analyzed. The results show that the deformation is mainly concentrated in the middle of the span before the initial weighting. The closer the horizontal and vertical stress is to the two ends, the greater the horizontal and vertical stress is, indicating that the middle and end of the roof are easy to damage. After the first weighting, the horizontal stress is mainly concentrated above the working face, that is, the position above the working face is easy to be damaged.

(3)Based on the theory of fracture mechanics, considering the influence of crack loca

-tion on roof breaking, the first weighting model of stope roof is established, the stress of roof under geological conditions of working face is analyzed, and the formula of first weighting step distance of stope is deduced. The relationship between the first weighting step and the fracture toughness, buried depth, artificial crack length and artificial crack position of the main roof is analyzed. The results show that the initial weighting step increases with the increase of fracture toughness. It decreases with the increase of buried depth and the decrease of artificial crack length. The closer the main control crack position is to the middle or end, the smaller the initial pressure step is, which is consistent with the numerical simulation results.

(4)According to the coordinated deformation mechanism of overlying strata, the action of immediate roof and support is transmitted to the basic roof by force, and the fracture mechanics model of periodic weighting of stope roof with damage crack is established. The formula of periodic weighting step distance of basic roof under the action of immediate roof is deduced. The effects of parameters such as the length of the main roof rock crack and the thickness of the immediate roof on the periodic weighting are analyzed. The results show that the fracture toughness of the main roof is approximately linear with the periodic pressure and is not affected by other parameters.

(5)Based on the analysis of mine pressure monitoring of S1223 working face in a coal mine in northern Shaanxi, the basic law of mine pressure appearance in the working face is summarized. According to the fracture mechanics model of the first weighting interval of the stope roof and the fracture mechanics model of the periodic weighting of the stope roof, the first weighting interval and the periodic weighting interval are predicted. The results are basically consistent with the measured data.

参考文献:

参考文献

[1]中国煤炭工业协会.煤炭行业发展年度报告(2022).

[2]沈孟飞.坚硬厚层顶板弱化前后采场矿压显现规律研究[D].安徽淮南:安徽理工大学,2014.

[3]于斌,刘长友,杨敬轩,等.坚硬厚层顶板的破断失稳及其控制研究[J].中国矿业大学学报,2013,42(3):343-348.

[4]何江,窦林名,王崧玮,等.坚硬顶板诱发冲击矿压机理及类型研究[J].采矿与安全工程学报,2017,34(6):1123-1126.

[5]谭云亮.矿山压力与岩层控制[M].北京:煤炭工业出版社,2011.

[6]Savage W Z,Swolfs H S,Powers P S.Gravitational stresses in long symmetric ridges and valleys[J].International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts,1985,22(5):291-302.

[7]Li C,Stillborg B.Analytical models for rock bolts[J].International Journal of Rock Mechanics and Mining Sciences,1999,36( 8):1013-1029.

[8]Holla L,Buizen M.Strata movement due to shallow longwall mining and the effect on ground permeability.1990.

[9]钱鸣高,石平五,许家林 矿山压力与岩层控制[M].徐州:中国矿业大学出版社.

[10]钱鸣高,缪协兴,何富连.采场“砌体梁”结构的关键块分析[J].煤炭学报,1994,1906):557-562.

[11]宋振骐.实用矿山压力控制[M].徐州:中国矿业大学出版社,1992.

[12]宋振骐,蒋宇静,刘建康.“实用矿山压力控制”的理论和模型[J].煤炭科技,2017,(2):1-10.

[13]钱鸣高,缪协兴,许家林,等.岩层控制的关键层理论[M].江苏徐州:中国矿业大学出版社,2000.

[14]钱鸣高,缪协兴,许家林.岩层控制中的关键层理论研究[J].煤炭学报,1996,21(3):223-230.

[15]郑凯歌,王林涛,李彬刚,等.坚硬顶板强矿压动力灾害演化机理与超前区域防治技术[J].煤田地质与勘探,2022,50(8):62−71.

[16]题正义,张峰,秦洪岩,等.基于板壳和断裂力学理论的上覆采空区积水危险性判定技术[J].煤田地质与勘探,2019,47(1):138–143.TI.

[17]陈新年,王景春,熊咸玉,等.煤巷复合顶板结构对其稳定性影响试验[J].煤田地质与勘探,2019,47(2):157–161.

[18]高峰,钱鸣高,缪协兴.基本顶给定变形下直接顶受力变形分析[J].岩石力学与工程学报,2000,19(2):4.

[19]弓培林,靳钟铭.大采高综采采场顶板控制力学模型研究[J].岩石力学与工程学报,2008,27(001):193-198.

[20]FENG Q, FU S, WANG C,et al. Analytical solution for fracture of stope roof based on Pasternak Foundation model[J]. Soil Mechanics and Foundation Engineering,2019,56(2):142-150

[21]刘长友,万志军,曹胜根.直接顶岩层力学特性对综放采场煤岩破坏的影响规律[J].矿山压力与顶板管理,2002,19(1):3.

[22]GONG T, XIA B, LU Y, et al. Study on the maximum pressure-causing stratum in longwall mining stope and its mechanics analysis[J]. Arabian Journal of Geosciences,2020,13(13):1-19

[23]LUO Z, XIE C, JIA N, et al. Safe roof thickness and span of stope under complex filling body[J]. Journal of Central South University,2013,20(12):3641-3647.

[24]杨登峰,陈忠辉,孙建伟,等.大采高长壁工作面顶板垮落的裂纹板力学模型[J].东南大学学报(自然科学版),2016,046(0z1):210-216.

[25]HU J, LEI T, ZHOU K, et al. Mechanism on simulation and experiment of pre-crack seam formation in stope roof[J]. Journal of Central South University, 2014, 21(4): 1526-1533.

[26]李新元,马念杰,钟亚平,等.坚硬项板断裂过程中弹性能量积聚与释放的分布规律[J].岩石力学与工程学报,2007,26(S1):2786-2793.

[27]曹永模.初次断裂期间顶板挠度、弯矩、应力和能量变化的解析解[J].能源技术与管理,2017,42(01):54-56.

[28]赵娜,王来贵.坚硬顶板初次垮落中的能量转化及释放研究[J].中国安全科学学报,2016,26(02):38-43.

[29]Jia Jinlong, Cao Liwen. Study on the fracture characteristics of thick hard limestone roof and its controlling technique[J]. Environmental Earth Sciences, 2017, 76 (17): 605-615.

[30]刘长友,杨敬轩,于斌,等.多采空区下坚硬厚层破断顶板群结构的失稳规律[J].煤炭学报,2014(3):395-403.

[31]杨敬轩,刘长友,于斌,等.坚硬厚层顶板群结构破断的采场冲击效应[J].中国矿业大学学报,2015,43(01):8-15.

[32]鞠金峰,许家林,王庆雄.大采高采场关键层“悬臂梁”结构运动型式及对矿压的影响[J].煤炭学报,2011,36(12):2115-2120.

[33]谷拴成,李金华,黄荣宾.采场直接顶对周期来压步距的影响[J].矿业安全与环保,2015,42(5):5.

[34]谷拴成,黄荣宾,苏培莉,等.直接顶岩层特性对综采工作面周期来压步距的影响[J].煤炭技术,2017(7):3.

[35]张杰.采高对浅埋煤层基本顶岩层来压步距的影响[J].辽宁工程技术大学学报:自然科学版,2009,28(2):4.

[36]孙闯,宋业杰.基于断裂力学的长壁工作面导水裂缝带高度预计[J].煤矿开采,2016,21(3):4.

[37]韩贵雷,韩立军,王延宁,等.厚层复合石灰岩顶板垮落特性试验研究[J].采矿与安全工程学报,2007(01):60-64.

[38]王作棠,辛林,付振坤,等.较坚硬火成岩老顶损伤垮落步距的计算预测[J],煤炭工程,2010(0);58-60.

[39]刘洋,伍永平.近浅埋煤层开采顶板垮落步距分析[J]煤开采,2009,14(06);10-12. Yu B. Behaviors of overlying strata in extra-thick coal seams using top-coal caving method[J]. Journal of Rock Mechanics and Geotechnical Engineering, 2016, 8(2): 238-247.

[40]Zhao Tong, Liu Chang you, Kaan Yet ilmezsoy. etal. Fractural structure of thick hard roof stratumusing long beam theory and numerical modeling[J]. Environmental Earth Sciences. 2017, 76(21):751-764.

[41]刘伟韬,刘士亮,霍志超,顶板导水裂隙带发育高度模拟与测试技术研究[J].工程勘察,2014,42(11):39-43.

[42]李振峰,靳晓敏.应用UDEC进行顶板“三带”范围划分的数值模拟研究[J].矿业安全与环保,2015,2(04):21-24.

[43]何东旭.深部环境下坚硬顶板预裂爆破弱化机理研究[D].江苏徐州:中国矿业大学,2015.

[44]Esterhuizen G S,Dolinar D R,Ellenberger J L,et al. Roof stability issues in underground limestone mines in the United States[J]. 2007.

[45]Esterhuizen G S,Bajpayee T S. Horizontal stress related failure in bedded mine roofs-insight from field observations and numerical models[C]//46th US Rock Mechanics / Geomechanics Symposium . OnePetro, 2012.

[46]Mark C,Gadde M.Global trends in coal mine horizontal stress measurements[J]. 2010.

[47]唐铁吾,刘大安,崔振东,等.煤矿顶板致裂水压力的断裂力学评估[J].煤炭学报,2020,45(S02):9

[48]缪协兴,黄艳利,巨峰,等.密实充填采煤的岩层移动理论研究[J].中国矿业大学学报,2012,41(06):863-867.

[49]缪协兴.条带改长壁固体密实充填开采理论与实践研究.中国煤炭学会成立五十周年高层学术论坛论文集[C].中国煤炭学会:2012:7.

[50]徐世烺,赵国藩,黄永逵,等.混凝土大型试件断裂能GF及缝端应变场[J].水利学报,1991(11):9.

[51]徐世烺.混凝土双K断裂参数计算理论及规范化测试方法[J].三峡大学学报:自然科学版,2002,24(1):1-8.

[52]吴瑶,徐世烺,吴建营,等.双K断裂准则在丹江口大坝安全性评定中的应用[J].水利学报,2015,46(3):7.

[53]于骁中.岩石和混凝土断裂力学[M]. 中南工业大学出版社,1991.

[54]Lajtal,E.Z. Int.Frac.Vol, 10, No.4. 1974

[55]Tada,H.ctal,The stress analysis of crack hand book.1973

[56]中国航空研究院. 应力强度因子手册[M]. 科学出版社, 1981.

[57]李金华,段东,岳鹏举,等.坚硬顶板强制放顶断裂力学模型研究[J].煤田地质与勘探,2018,46(6):5.

[58]王进学,王家臣,陈忠辉."两硬"浅埋深厚煤层顶煤顶板运移规律研究[J].采矿与安全工程学报,2006,23(2):5

[59]史振飞. 厚煤层坚硬顶板预裂爆破强制放顶技术实践[J]. 煤矿现代化, 2020(1):4.

中图分类号:

 TU313    

开放日期:

 2023-06-12    

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