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Mining Science and Technology 2009年第6期19卷 724-729页

作者： LIU Hai-bo cheng yuan-ping SONG Jian-cheng SHANG Zheng-jie WANG Liang National Engineering Research Center for Coal ＆ Gas Control China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China Zhengzhou Coal Industrial Group Corporation Ltd. Zhengzhou Henan 452371 China

Numerical simulations and field tests were used to investigate the changes in ground stress and deformation of, and gas flow from, a protected coal seam under which an extra-thin coal seam was drilled. The geological conditions were: 0.5 meter mining height, 18.5 meter coal seam spacing and a hard limestone/fine sandstone inter-stratum. For these conditions we conclude: 1) the overlying coal-rock mass bends and sinks without the appearance of a caving zone, and 2) the protected coal seam is in the bending zone and undergoes expansion deformation in the stress-relaxed area. The deformation was 12 mm and the relative defor- mation was 0.15%. As mining proceeds, deformation in the protected layer begins as compression, then becomes a rapid expansion and, finally, reaches a stable value. A large number of bed separation crannies are created in the stress-relaxed area and the permeability coefficient of the coal seam was increased 403 fold. Grid penetration boreholes were evenly drilled toward the protected coal seam to affect pressure relief and gas drainage. This made the gas pressure decrease from 0.75 to 0.15 MPa, the gas content decrease from 13 to 4.66 m3/t and the gas drainage reach 64%.

关键词： extra-thin protective coal seam drilling pressure relief expansion deformation gas drainage

Principle and engineering application of pressure relief gas drainage in low permeability outburst coal seam

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Mining Science and Technology 2009年第3期19卷 342-345,351页

作者： LIU lin cheng yuan-ping WANG Hai-feng WANG Liang MA Xian-qin National Engineering Research Center for Coal ＆ Gas Control China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China Chongqing Institute of China Coal Research Institute Chongqing 400037 China

With the increase in mining depth, the danger of coal and gas outbursts *** order to drain coal gas effectively and to eliminate the risk of coal and gas outbursts, we used a specific number of penetration boreholes for draining of pressure relief *** on the principle of overlying strata movement, deformation and pressure relief, a good effect of gas drainage was *** practice in the Panyi coal mine has shown that, after mining the C11coal seam as the protective layer, the relative expansion deformation value of the protected layer C13 reached 2.63%, The permeability coefficient increased 2880 times, the gas drainage rate of the C13 coal seam increased to more than 60%, the amount of gas was reduced from 13.0 to 5.2 m3/t and the gas pressure declined from 4.4 to 0.4 MPa, which caused the danger the outbursts in the coal seams to be *** result was that we achieved a safe and highly efficient mining operation of the C13 coal seam.

关键词： protective layer mining technology principle drainage of pressure relief gas engineering application

Fracture evolution and pressure relief gas drainage from distant protected coal seams under an extremely thick key stratum

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Journal of China University of Mining and Technology 2008年第2期18卷 182-186页

作者： WANG Liang cheng yuan-ping LI Feng-rong WANG Hai-feng LIU Hai-bo National Engineering Research Center for Coal ＆ Gas control China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China Haizi Coal Mine Huaibei Mining Industry Group Huaibei Anhui 235000 China

When an extremely thick rock bed exists above a protected coal seam in the bending zone given the condition of a mining protective seam, this extremely thick rock bed controls the movement of the entire overlying stratum. This extremely thick rock bed, called a ＂main key stratum＂, will not subside nor break for a long time, causing lower fractures and bed separations not to close and gas can migrate to the bed separation areas along the fractures. These bed separations become gas enrichment areas. By analyzing the rule of fracture evolution and gas migration under the main key stratum after the deep protective coal seam has been mined, we propose a new gas drainage method which uses bore holes, drilled through rock and coal seams at great depths for draining pressure relief gas. In this method, the bores are located at a high level suction roadway （we can also drill them in the drilling field located high in an air gateway）. Given the practice in the Haizi mine, the gas drainage rate can reach 73% in the middie coal group, with a gas drainage radius over 100 m.

关键词： extremely thick key stratum protective seam exploitation fracture evolution gas drainage distant borehole drilling

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PVC输送带点燃温度判据及应用

燃烧科学与技术 2006年第5期12卷 438-441页

作者：季经纬程远平中国矿业大学能源与安全工程学院徐州221008

利用锥形量热计对800S PVC整芯阻燃输送带的点燃性能进行了实验研究；在实验数据的基础上,采用传热模型计算出实验时输送带的点燃温度,其平均点燃温度为384℃．利用此温度判据,对输送带在实验巷道中火焰蔓延情况进行了数值模拟．计算结... 详细信息

利用锥形量热计对800S PVC整芯阻燃输送带的点燃性能进行了实验研究；在实验数据的基础上,采用传热模型计算出实验时输送带的点燃温度,其平均点燃温度为384℃．利用此温度判据,对输送带在实验巷道中火焰蔓延情况进行了数值模拟．计算结果表明,在小尺寸实验巷道中,1m/s的风速条件下,600 s时间内火焰在输送带表面上蔓延的长度约为0．3 m．

关键词： PVC输送带点燃判据火焰蔓延数值模拟

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矿井火灾中火场能见度的估算方法

中国矿业大学学报 2006年第2期35卷 149-152,156页

作者：季经纬程远平中国矿业大学能源与安全工程学院江苏徐州221008

从火灾烟气减光性的定义及其描述参数出发,推导建立了矿井火灾过程中风流速度、烟气中毒性气体体积浓度与火源热释放速率及能见度的关系式,并提出了矿井火灾过程中火场能见度的简单估算方法.结合输送机胶带燃烧性能的锥形量热计实验结果... 详细信息

从火灾烟气减光性的定义及其描述参数出发,推导建立了矿井火灾过程中风流速度、烟气中毒性气体体积浓度与火源热释放速率及能见度的关系式,并提出了矿井火灾过程中火场能见度的简单估算方法.结合输送机胶带燃烧性能的锥形量热计实验结果,计算出当火源热释放速率按bt2发展变化时CO,CO2的体积浓度及对应的火场能见度.另外还计算了火场能见度为5 m和10 m时所必需的风速.计算结果表明,利用能见度指标计算出来的通风风速可保证烟气中CO,CO2的浓度远低于人的安全极限.

关键词：矿井火灾能见度烟气锥形量热计

Resistance of Cement-based Grouting Materials with Nano- SiO_(2) Emulsion to Chloride Ion Penetration

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 114-119页

作者： LI Shuiping cheng Jian WEI Chao yuan Bin YU chengxiao College of Architectural Science and Engineering Yangzhou UniversityYangzhou 225127China

The chloride penetration resistance of cement-based grout materials was improved by nano-silica *** of mixtures containing different nano-silica particles or emulsions were exposed in sodium chloride solutions of specific concentrations with different test *** properties of the mixes were assessed in terms of weight loss and compressive strength.X-ray diffraction(XRD)and scanning electron microscopy(SEM)of mixes were performed to analysis the phase evolution and *** results demonstrated that the introduction of nano-SiO_(2) emulsion significantly decreased the compressive strength loss and calcium hydroxide(CH)crystal content of hydration production,and then enhanced the resistance of cement-based grouting materials to chloride ion *** improvement derives from the filling and pozzolanic effects of nano-SiO_(2) particles,which were incorporated via an emulsion and attributed to a well dispersion in grouting matrix.

关键词： grouting materials nano-SiO_(2)emulsion chloride ion penetration,weight loss strength loss

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航天器多脉冲悬停控制的非线性方法

宇航学报 2016年第12期37卷 1466-1472页

作者：程博袁建平马卫华西北工业大学航天学院西安710072 北京宇航系统工程研究所北京100076 航天飞行动力学技术重点实验室西安710072

为解决连续推力空间悬停控制技术对航天器控制推进系统要求较高、工程上难于实现的问题,提出基于Clohessy-Wiltshire方程的多脉冲悬停控制方法。以轨道要素外推的飞行状态非线性预测方法和脉冲悬停控制量优化算法,对悬停脉冲进行了优化... 详细信息

为解决连续推力空间悬停控制技术对航天器控制推进系统要求较高、工程上难于实现的问题,提出基于Clohessy-Wiltshire方程的多脉冲悬停控制方法。以轨道要素外推的飞行状态非线性预测方法和脉冲悬停控制量优化算法,对悬停脉冲进行了优化,可以实现主动航天器在目标航天器附近任意点的近似稳定悬停。给出的多脉冲悬停控制方法及控制量非线性优化算法考虑了地球非球形引力摄动J2项影响,补偿了Clohessy-Wiltshire方程的线性化误差,能有效提高悬停精度。仿真结果表明,多脉冲悬停控制方法的燃料消耗与连续推力悬停方法相比没有明显增加,不会对主动航天器带来过大的燃料消耗压力。

关键词：航天器悬停速度脉冲非线性控制量优化

煤与瓦斯突出预测的改进差分进化神经网络模型研究

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中国矿业大学学报 2009年第3期38卷 439-444页

作者：杨敏汪云甲程远平中国矿业大学环境与测绘学院江苏省资源环境信息工程重点实验室江苏徐州221116 中国矿业大学安全工程学院江苏徐州221116

鉴于常规煤与瓦斯突出BP预测模型的不足,将改进DE算法用于BP网络模型参数的优化及训练,提出结合两者优点的改进差分进化神经网络(IDEBP)煤与瓦斯突出预测模型.模型通过对变异模式、变异交叉因子自适应确定等改进,有效提高了标准DE的性能... 详细信息

鉴于常规煤与瓦斯突出BP预测模型的不足,将改进DE算法用于BP网络模型参数的优化及训练,提出结合两者优点的改进差分进化神经网络(IDEBP)煤与瓦斯突出预测模型.模型通过对变异模式、变异交叉因子自适应确定等改进,有效提高了标准DE的性能.实现了DE全局优化搜索与BP自适应、自学习的有机结合,稳健性得到加强,更能充分辨识煤与瓦斯突出样本的复杂非线性知识.以36组工程实例数据,进行了IDEBP和DEBP模型与BP模型仿真对比实验.结果表明:该模型能有效避免常规BP的不足,在收敛迅速、结果辨识和预测精度等方面均大为提高,为瓦斯智能预测提供了新的解决方案.

关键词：煤与瓦斯突出预测差分进化神经网络

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利用覆岩移动特性实现煤与瓦斯安全高效共采

辽宁工程技术大学学报（自然科学版） 2006年第2期25卷 168-171页

作者：夏红春程远平柳继平中国矿业大学建筑工程学院江苏徐州221008 中国矿业大学能源科学与工程学院江苏徐州221008 兖州矿业集团第37工程处山东邹城273500

为了实现高瓦斯煤层群条件下煤与瓦斯的安全高效共采,运用数值模拟和现场试验相结合的方法,对远距离下保护层开采的采动效应进行了分析与研究。结果表明:下保护层开采使覆岩产生不同程度的卸压,煤体产生膨胀变形,生成大量的次生裂隙,从... 详细信息

为了实现高瓦斯煤层群条件下煤与瓦斯的安全高效共采,运用数值模拟和现场试验相结合的方法,对远距离下保护层开采的采动效应进行了分析与研究。结果表明:下保护层开采使覆岩产生不同程度的卸压,煤体产生膨胀变形,生成大量的次生裂隙,从而导致煤体的透气性增加,为远程卸压瓦斯的抽放创造了有利条件;同时,覆岩的水平应力分布也发生了改变,由原始的水平压应力变为拉应力,从而导致了水平位移的产生,在该位置形成丰富的竖向裂隙,为瓦斯的运移提供了通道。在高瓦斯煤层群条件下,可以通过合理的开采顺序和有效的瓦斯抽放方法,实现煤与瓦斯两种资源的安全高效共采。

关键词：高瓦斯煤层群煤与瓦斯共采数值模拟

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地铁排烟风亭与出入口合理的相对位置

西南交通大学学报 2005年第5期40卷 591-594页

作者：顾正洪程远平周世宁中国矿业大学能源与安全工程学院江苏徐州221008

为防止发生地铁火灾时排烟风亭排出的烟气通过出入口倒流回车站,用FDS(火灾动力学模拟器)场模拟软件对火灾发生时排烟口烟气蔓延、分布规律及其影响因素进行了研究.模拟结果表明:排烟风亭排出的烟气倒流回出入口的可能性大小与烟气温度... 详细信息

为防止发生地铁火灾时排烟风亭排出的烟气通过出入口倒流回车站,用FDS(火灾动力学模拟器)场模拟软件对火灾发生时排烟口烟气蔓延、分布规律及其影响因素进行了研究.模拟结果表明:排烟风亭排出的烟气倒流回出入口的可能性大小与烟气温度、其与出入口的空间距离、自然风的方向和大小等因素有关.现场试验结果证实了模拟结果的正确性.

关键词：地铁火灾烟气排烟风亭出入口数值模拟