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and 20-30 m in the gradient direction. Key words: fully mechanized face; numerical simulation; grid adaptive technology; ventilation quantity distribution of working face 掌握综采工作面采空区漏风流动规律,对预防采空区自然发火具有重要作...难.为了使测试结果更加合理,整个测风过程由同一个专业测风员完成,以减少人为误差,测试结果如图4所示. 图4 工作面倾向上风量分布图 Fig.4 Ventilation quantity distribution of working face in gradient direction 从图4可知:模拟得到的工作面风量分布趋势与实测结果基本一致.工作面上的风量分布不均匀......
in working chamber caused by thrust speed variation and improve the precision of earth pressure balance (EPB) control system, a new EPB control system was designed based on thrust speed feedforward and earth pressure feedback control. The mathematical model of earth pressure in working chamber was proposed. According to the relationship among thrust speed, screw conveyor speed and earth pressure described......
;CFG桩间距;桥台桩;工作性状;离心机试验 中图分类号:TU473 文献标志码:A 文章编号:1672-7207(2017)03-0820-10 Analysis on working properties... is inhibited by the existence of CFG piles compared with natural foundation. Key words: soft soil; CFG pile spacing; abutment piles; working properties; centrifuge experiment 在软土地基上,桥头路基填土对邻近桥台桩基的影响较复杂,路基荷载会导致......
tunnel; working face; blow-out failure; upper bound analysis; support pressure 随着城市规模扩大,为了满足大流量跨区域快速交通要求,隧道成为发展的主流方向,与此同时,城市轨道交通建设也从原来单线隧道逐渐向一次成型的双线方向发展.目前,上海,南京,杭州,武汉和广州等地均采用泥水盾构来进行隧道建设.在隧道掘进过程中,常因覆......
distribution of mass fraction; influence factor; working characteristics 金川集团矿山在应用粒度小于5 mm棒磨砂,粒度小于12 mm破碎废石和粒度小于20 mm戈壁砂等粗骨料进行下向分层进路充填时发现,粗骨料料浆在自流输送过程中,管道磨损和堵管的现象常有发生,同时充填体在采场内呈现层状结构,降低了胶结体强度和整体稳定性,给采矿高效安全生产带来......
易自燃煤层放顶煤开采工作面合理长度分析 李钢钢1,李宗翔2,贾进章2 (1.辽宁工程技术大学,资源与环境工程学院,辽宁,阜新,123000;2.辽宁工程技术大学,安全科学与工程学院,辽宁,阜新,123000) 摘要:以采空区自然发火危险为约束条件,用采空区场流方法(数值模拟)和自燃三带理论,结合实例,研究放项煤开采工作面合理长度问题.得到工作面长度安全临界值与煤的最短自然发火期成正比关系.通过现场测定风量和采空区气体浓度分布,得到在当前工作面特定采空区流场环境下的自燃氧化带宽度和模型基础参数,数值模拟出不同工作面长度的采空区自燃氧化区宽度的变化关系;回归得到,在理论上,工作面长度与自燃氧化带宽度近似服从二次曲线关系.分析中给出了自燃安全判别量和自燃安全区间. 关键词:工作面长度; 自然发火; 放顶煤开采; 自燃三带; 安全判别量; working face length......
Trans. Nonferrous Met. Soc. China 22(2012) 2072-2079 Influence of sequence of cold working and aging treatment on mechanical behaviour of 6061 aluminum alloy Mostafa MANSOURINEJAD1, Bahman... 38156-8-8349, Iran Received 17 November 2011; accepted 27 February 2012 Abstract: The influence of combination of different designated precipitation hardening and cold working on the tensile properties......
Supporting optimization of working well in shield construction with tunnel followed by well excavation MO Haihong1, YANG Chunshan1, 2, CHEN Junsheng1, CHEN Lingwei1 (1. School of Civil Engineering... experience analogy method. Key words: shield tunnel; working well; supporting optimization; orthogonal experiment; tunnel followed by well excavation; segment opening; double-sided elastic foundation beam 在盾构......
.) for the purpose of explaining the working process and evaluating practical effects. The results show that this technique has the advantages of easy manipulation, rapid deposition, and wide composition......
experiment. The properties of the bus are as follows:the tensile strength σb is 238 MPa, the conductivity (v.s. IACS) is 54.3%, and the current-carrying capacity is beyond 3.1kA during working process......