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Numerical simulation of coal wall cutting and lump coal formation in a fully mechanized mining face

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International Journal of Coal Science & Technology 2021年第6期8卷 1371-1383页

作者： Yong Yuan Shengzhi wang wenmiao wang Cheng Zhu Key Laboratory of Deep Coal Resource Mining(CUMT) Ministry of EducationChina University of Mining and TechnologyXuzhou 221116JiangsuChina State Key Laboratory of Coal Resources and Safe Mining and School of Mines China University of Mining and TechnologyXuzhou 221116JiangsuChina

It is difficult to accurately calculate the lump coal rate in a fully mechanized mining face.Therefore,a numerical simulation of the coal wall cutting process,which revealed the crack expansion,development,evolution in the coal body and the corresponding lump coal formation mechanism,was performed in PFC2D.Moreover,a correlation was established between the cutting force and lump coal formation,and a statistical analysis method was proposed to determine the lump coal rate.The following conclusions are drawn from the results:(1)Based on a soft ball model,a coal wall cutting model is established.By setting the roller parameters based on linear bonding and simulating the roller cutting process of the coal body,the coal wall cutting process is effectively simulated,and accurate lump coal rate statistics are provided.(2)Under the cutting stress,the coal body in the working face underwent three stages—microfracture generation,fracture expansion,and fracture penetration—to form lump coal,in which the fracture direction is orthogonal to the cutting pressure chain.Within a certain range from the roller,as the cutting depth of the roller increased,the number of new fractures in the coal body first increases and then stabilizes.(3)Under the cutting stress,the fractured coal body is locally compressed,thereby forming a compact core.The formation and destruction of the compact core causes fluctuations in the cutting force.The fluctuation amplitude is positively related to the coal mass.(4)Because the simulation does not consider secondary damage in the coal,the simulated lump coal rate is larger than the actual lump coal rate in the working face;this deviation is mainly concentrated in large lump coal with a diameter greater than 300 mm.

关键词： Fully mechanized face Lump coal rate Fracture evolution Cutting force Particle flow simulation

Research on the "three shells" cooperative support technology of large-section chambers in deep mines

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International Journal of Mining Science and Technology 2021年第4期31卷 665-680页

作者： Cheng Zhu Yong Yuan wenmiao wang Zhongshun Chen Shengzhi wang Huiwei Zhong Key Laboratory of Deep Coal Resources Mining Ministry of Education of ChinaChina University of Mining and TechnologyXuzhou 221116China School of Mines State Key Laboratory of Coal Resources&Safe MiningChina University of Mining and TechnologyXuzhou 221116China

The"three shells"cooperative support technology was proposed herein according to both the large deformation of the rock surrounding large-section chambers in deep mines and the precarious stability of the support structures therein.The development range of the plastic zone in the surrounding rock was controlled by a stress shell to reduce the difficulty of controlling the surrounding rock.Additionally,the residual strength of the rock mass in the plastic zone and the self-bearing capacity of the surrounding rock were improved by a reinforced load-bearing shell.Furthermore,a passive load-bearing shell could restore the triaxial stress state of the surrounding rock on the free surface,reduce the influence of the external environment on the surrounding rock,and reinforce the surrounding rock with the strength of the shell.Reasonable layouts of large-section chambers were determined by analyzing the control effect of the stress shell on the surrounding rock under three kinds of in situ stress fields.The orthogonal test method was applied to reveal the influences of different support parameters in the reinforced loadbearing shell and passive load-bearing shell on the surrounding rock stability.The surrounding rock control effect of the"three shells"collaborative support technology was analyzed through numerical simulation and field monitoring.The results show that the maximum displacement between the roof and floor of the coal preparation chamber in the Xinjulong coal mine was approximately 48 mm,and the maximum displacement between its two sides was approximately 65 mm,indicating that the technology proposed herein could meet the long-term control requirements of the surrounding rock stability for large-section chambers in deep mines.

关键词： Deep mining Large-section chamber "Three shells"cooperative support Reasonable layout Surrounding rock control

Phase Ⅱ study of apatinib in combination with oral vinorelbine in heavily pretreated HER2-negative metastatic breast cancer and clinical implications of monitoring ctDNA

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Cancer Biology & Medicine 2021年第3期18卷 875-887页

作者： Anjie Zhu Peng Yuan Nanlin Hu Mingzhou Li wenmiao wang Xue wang Jian Yue Jiayu wang Yang Luo Fei Ma Pin Zhang Qing Li Binghe Xu Shanbo Cao Giuseppe Lippi Yoichi Naito Mohammed A.Osman Gustavo N.Marta Gianluca Franceschini Armando Orlandi Department of Medical Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Department of BreastOncologyPeking University Cancer Hospital&InstituteBeijing 100142China Department of VIP Medical Services National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of Pathology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Acorn Med Biotechnology Co. Ltd.Beijing 101102China Section of Clinical Biochemistry University Hospital of VeronaVeronaVerona 37100Italy Department of Breast and Medical Oncology National Cancer Center Hospital EastKashiwa 277-8577Japan Clinical Oncology General Organization for Teaching HospitalsCairo 11435Egypt Department of Radiation Oncology Hospital Sírio-LibanêsSao Paulo 01308-050Brazil Multidisciplinary Breast Center Fondazione Policlinico Universitario A.Gemelli IRCCSUniversitàCattolica del Sacro CuoreRome 00176Italy Unit of Medical Oncology Fondazione Policlinico Universitario A.Gemelli IRCCSRoma 00176Italy

Objective:Apatinib is an oral TKI targeting VEGFR-2.Single-agent apatinib treatment has been shown to produce an objective response in patients with pretreated m BC.Oral vinorelbine also holds promise as a treatment of choice in patients with m BC.This study aimed to investigate the efficacy and safety of the oral vinorelbine-apatinib combination in patients with pretreated m BC.In addition,we detected gene variants in ct DNA to explore the therapeutic implications.Methods:This study enrolled patients with HER2-negative m BC who were pretreated with anthracycline/taxanes.Patients were treated with apatinib at 500 mg/425 mg daily plus oral vinorelbine 60 mg/m2 on days 1,8,and 15 of every cycle(3 weeks).The primary endpoint was PFS.The secondary endpoints were ORR,CBR,OS,and safety.Patients eligible for ct DNA detection were evaluated before and during treatment.Results:Forty patients were enrolled.The median PFS was 5.2 months(95%CI,3.4–7.0 months),and the median OS was 17.4 months(95%CI,8.0–27.0 months).The ORR was 17.1%(6/35),and the CBR was 45.7%(16/35).The most common AEs included gastrointestinal reaction,myelosuppression,and hypertension.In 20 patients,ct DNA was detected at baseline and during treatment.A significant difference was found in PFS for undetected vs.detected baseline ct DNA(13.9 months vs.3.6 months,P=0.018).Conclusions:All-oral therapy with apatinib plus vinorelbine displayed objective efficacy in patients with heavily pretreated HER2-negative m BC,with acceptable and manageable toxicity profiles.Patients with no gene variant detected and lower variant allele frequencies in ct DNA at baseline showed longer PFS.

关键词： Metastatic breast cancer apatinib oral vinorelbine ct DNA

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深部煤矿井下采煤-充填空间优化布局方法

中国矿业大学学报 2023年第2期52卷 286-299页

作者：袁永朱成王文苗陈忠顺梁小康中国矿业大学深部煤炭资源开采教育部重点实验室江苏徐州221116 中国矿业大学矿业工程学院江苏徐州221116 华南理工大学土木与交通学院广东广州510641 榆林汇森煤矿建设运营有限责任公司冯家塔分公司陕西榆林719000

针对深部采选充一体化矿井内采煤-充填空间协调布局问题,采用德尔菲-层次分析法确定了影响采、充空间布局各因素的相对权重,推导得到了采、充空间布置参数与工艺参数的动态调整方程,模拟研究了适用于“控、防、留”3类工程需求的采-充... 详细信息

针对深部采选充一体化矿井内采煤-充填空间协调布局问题,采用德尔菲-层次分析法确定了影响采、充空间布局各因素的相对权重,推导得到了采、充空间布置参数与工艺参数的动态调整方程,模拟研究了适用于“控、防、留”3类工程需求的采-充空间布局策略,构建了采-充空间优化布局决策模型.结果表明:选用采-充空间集中布置、局部密实充填方案时,地表沉陷控制与冲击地压防治效果最好;基于“以采定充”、采充空间分散布置的限定条件,新巨龙煤矿井下需同时布置1303N-1,1304N两个充填面以满足伴生矸石就地消化需求,且整体充实率不应低于55%,同时,为确保留巷围岩稳定,巷旁加强充填带的充实率需达80%以上、宽度不得小于10 m.

关键词：权重分析参数动态调整布局策略布局决策模型采充协调

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颗粒增强铁基复合材料拉伸应力场数值分析

特种铸造及有色合金 2005年第4期25卷 254-256页

作者：邓刚宋延沛王文焱李洛利河南科技大学

采用有限元方法分析了颗粒增强铁基复合材料强度和应力与颗粒形状、尺寸以及体积分数的关系。结果表明,颗粒尖锐化会导致颗粒尖端应力集中和基体内的应变集中。同时,颗粒长径比增大,颗粒的应力集中也增大;颗粒尺寸减小和体积分数增加都... 详细信息

采用有限元方法分析了颗粒增强铁基复合材料强度和应力与颗粒形状、尺寸以及体积分数的关系。结果表明,颗粒尖锐化会导致颗粒尖端应力集中和基体内的应变集中。同时,颗粒长径比增大,颗粒的应力集中也增大;颗粒尺寸减小和体积分数增加都有助于提高复合材料的强度。

关键词：铁基复合材料有限元法应力集中应变集中长径比

深部大断面巷硐围岩稳定性评价与布置方式研究

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采矿与安全工程学报 2020年第1期37卷 11-22页

作者：朱成袁永袁超峰王文苗孟朝贵中国矿业大学矿业工程学院江苏徐州221116 煤炭资源与安全开采国家重点实验室江苏徐州221116

针对深部大断面巷硐围岩变形量大、支护困难等特点,采用FLAC^3D数值计算方法,探讨围岩内最大主应力峰值区的时空演化规律,分析最大主应力峰值区对围岩变形破坏的控制作用,提出塑性区发育范围判定与围岩稳定性综合评价的方法。根据地应... 详细信息

针对深部大断面巷硐围岩变形量大、支护困难等特点,采用FLAC^3D数值计算方法,探讨围岩内最大主应力峰值区的时空演化规律,分析最大主应力峰值区对围岩变形破坏的控制作用,提出塑性区发育范围判定与围岩稳定性综合评价的方法。根据地应力场类型、侧压系数、巷硐轴向与最大水平主应力夹角的差异,共设计151种数值模拟方案,研究3类地应力场中构造应力对大断面巷硐围岩稳定性的影响。结果表明:围岩塑性区发育与最大主应力峰值区存在运移一致性,基于边界应力系数K可判定塑性区发育范围,并通过遍历数值计算确定K值为0.96;在σH型应力场中,当λH=λh时,巷硐最优布置角度为30°,当λH≠λh时,巷硐平行于最大水平主应力方向布置最有利于围岩稳定;在σHv型应力场中,巷硐最佳布置角度是与最大水平主应力成0°~15°夹角;在σv型应力场中,当λH=λh时,巷硐无最优布置角度,当λH≠λh时,巷硐布置应遵循最大水平应力理论。

关键词：数值计算最大主应力峰值区边界应力系数围岩稳定性

2007年度“中国·北京·现代”建筑创作交流会

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建筑创作 2007年第6期 30-37页

作者：王雯淼 <建筑创作>杂志社

2007年5月10、11日，“中国·北京‘现代”建筑创作交流会在北京隆重举行。这场交流活动由中国建筑设计研究院、北京市建筑设计研究院、上海现代建筑设计集团有限公司三家单位共同发起，是继去年在上海华东建筑设计院成功举办后的第二... 详细信息

2007年5月10、11日，“中国·北京‘现代”建筑创作交流会在北京隆重举行。这场交流活动由中国建筑设计研究院、北京市建筑设计研究院、上海现代建筑设计集团有限公司三家单位共同发起，是继去年在上海华东建筑设计院成功举办后的第二届交流活动，今年移师到中国建筑设计研究院举行。

关键词：北京市建筑设计研究院中国建筑设计研究院建筑创作交流会上海现代建筑设计集团交流活动建筑设计院

井下煤矸分选硐室群结构特征与紧凑型布局方法

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中国矿业大学学报 2021年第3期50卷 469-478页

作者：朱成袁永陈忠顺王文苗申海生许哲扬中国矿业大学深部煤炭资源开采教育部重点实验室矿业工程学院江苏徐州221116 呼伦贝尔东明矿业有限责任公司东明露天矿内蒙古呼伦贝尔021000

针对井下煤矸分选硐室群优化布置难题,采用理论分析、数值模拟与现场调研相结合的研究方法,分析了煤矸分选硐室群的主要结构特征,探讨了煤矸分选硐室群紧凑型布局原则,提出了煤矸分选硐室群紧凑型布局方法,得到了硐室合理间距判别公式.... 详细信息

针对井下煤矸分选硐室群优化布置难题,采用理论分析、数值模拟与现场调研相结合的研究方法,分析了煤矸分选硐室群的主要结构特征,探讨了煤矸分选硐室群紧凑型布局原则,提出了煤矸分选硐室群紧凑型布局方法,得到了硐室合理间距判别公式.结果表明:煤矸分选硐室群具有整体断面尺寸大、主硐室宽高比小于1、巷道化布置及流线化回路布局的结构特点;煤矸分选硐室群布置应遵循主硐室优先布置、主硐室间平行布置、主辅硐室垂直布置、非等高巷硐渐进式过渡、尖角区域倒角过渡的基本原则;缩小主硐室间距是实现煤矸分选硐室群紧凑型布局的重要途径,主硐室间距不仅需要确保岩柱稳定,还应满足原煤入选要求.

关键词：煤矸分选硐室群结构特征布置原则主硐室间距紧凑型布局

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胡越:走建筑的路,源于发自内心的喜爱

建筑创作 2007年第2期 116-119页

作者：王雯淼张燕 <建筑创作>杂志社

胡越,1986年毕业于北京建筑工程学院建筑系本科,毕业后在北京市建筑设计研究院工作至今。现任院总建筑师,教授级高级建筑师,中央美术学院建筑学院课程教授。1997年获得一级注册建筑师资格。现为中国建筑学会理事,中国建筑学会建筑师分... 详细信息

胡越,1986年毕业于北京建筑工程学院建筑系本科,毕业后在北京市建筑设计研究院工作至今。现任院总建筑师,教授级高级建筑师,中央美术学院建筑学院课程教授。1997年获得一级注册建筑师资格。现为中国建筑学会理事,中国建筑学会建筑师分会和体育建筑分会理事。2003年荣获北京市有突出贡献的科学技术管理专家,享受国务院特殊津贴专家,2006年中国设计业十大杰出青年。曾作为主持人和方案设计人先后主持设计摩洛哥游泳馆、国家经贸委综合楼、豪威大厦、北京国际金融大厦、望京36号地综合楼、秦皇岛体育馆、望京36号地高层住宅、望京科技园二期等工程。现正负责2008年奥运会五棵松文体中心的设计工作。其主持设计的北京国际金融大厦获1995年北京十佳建筑、北京市第八届优秀工程设计一等奖、2000年建筑部优秀设计一等奖、全国优秀工程设计金奖、九十年代北京十大建筑、第二届詹天佑土木工程大奖。

关键词：北京市建筑设计研究院中国建筑学会注册建筑师北京建筑工程学院中央美术学院科学技术管理建筑学院