共查询到19条相似文献,搜索用时 703 毫秒
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锦屏电站辅助洞为A、B线的上下行单线隧道,线间距35 m,单线长175 km,由于隧道埋深大且无任何条件修建斜竖井做到长隧短打,只能从近东西向相向掘进,同时又由于工程的西端场地极其狭窄,不能满足有轨运输施工条件。通过技术论证,大胆创新,引入公路运营通风的理念,将射流通风运用于本工程的施工通风,从理论研究结合现场通风测试验证,成功地解决了巷道式射流风机选型、布置及通风管理等关键技术。通过双孔独头掘进9600 m的施工通风效果检测表明,洞内空气质量的各项指标均达到国家环卫标准,实现内燃作业、无轨运输,取得了 相似文献
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地质勘探坑道的特点是独头坑道多,掘进速度快,地質变化大,时间利用短。我队有的基本坑道長度达600公尺左右,一个坑口的总長度达3000公尺。坑道断面为3.6~4.4平方公尺,每个坑道內經常保持开动二台风鑽(最高达到四台),采取三班連續作业,一次放炮的炸药总消耗为20~40公斤。坑內工作人員在30人左右。在高度矽化(石英岩、石灰岩)及含有毒素的矿体(汞矿、黄铁矿)中掘进。因此,对通风工作提出了一系列的独特的要求。例如,如何根据工作面及季节的变化及时調整通风系統,如何保 相似文献
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结合金龙隧道施工通风方案的确定,阐述根据隧道的长度、掘进坑道的断面大小、施工方法和设备条件等诸多因素来确定隧道施工通风的方式、方法。 相似文献
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青藏铁路透壁通风管通风路基模型试验及初始温度场特征 总被引:9,自引:2,他引:7
通风路基作为一种积极主动保护冻土路基的冷却调控技术能有效的抬升多年冻土上限, 保护冻土路基的稳定性. 目前实体试验工程通风路基一般采用路基内预埋实体混凝土管或PVC管, 管壁不能透风, 管壁与土体间主要通过热传导进行换热. 一种管壁开孔、可以透风的新型通风管--"透壁通风管"既能以管内空气间的对流带走管内热量; 因其管壁透风, 低温的冷空气可以透过管壁的大孔眼穿透到通风管周围的介质中, 直接与其进行热交换, 从而改善传统通风管换热模式. 为探索透壁通风管在青藏铁路路基中的实际温控效果而进行了青藏铁路透壁通风管路基现场试验, 试验路基短期监测资料的分析结果显示, 透壁通风管对青藏铁路路基具有良好的冷却能力, 可在一定程度上抬升冻土上限; 透壁通风管路基经填土级配优化重组后更能充分发挥其路基冷却效果 相似文献
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介绍了煤矿送料孔、通风孔及救援孔等工程钻孔的钻进工艺及所用器具,并通过中国神华集团的施工实例对此类工程钻孔的前导钻进及扩孔钻进技术进行了较为详细的探讨。 相似文献
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通过老石旦煤矿缓坡斜井通风立眼的施工,叙述了钻遇采空区的几项施工关键技术。针对大口径通风井过采空区、井较深、井径较大的特点,采用大孔径反井成孔工艺;导向孔采用无线随钻定向技术,后改用无磁单点测斜潜孔锤定向技术;采用技术套管隔离的方法进行了管底特殊处理,保证技术套管顺利起拔;悬空固井技术,大直径套管人工柔性井底的制作等;对大孔径反井施工工艺技术进行了系统全面介绍,并对反井施工过程中发现的问题及取得成果进行的总结,为类似工程的施工具有示范效应。 相似文献
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Summary Solving ventilation networks of natural air splitting is a classical problem in mine ventilation. A common approach to this problem is to formulate it based on Kirchhoff's voltage and current laws and obtain the solution by an iterative technique known as the Hardy Cross method. In this paper, it is shown that the problem can be formulated and analysed as an unconstrained optimization (minimization) problem. The computational experience with the method of conjugate gradients is also discussed. 相似文献
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Characteristics of multiple-fan ventilation networks 总被引:1,自引:0,他引:1
Y. J. Wang 《Geotechnical and Geological Engineering》1984,2(3):229-243
Summary The definitions of system pressure loss (mine head) and system resistance, which are traditionally associated with single-fan networks, are applied to multiple-fan ventilation networks. The system characteristics, relations among air power, pressure loss, air quantity and resistance, are analysed by introducing the concept of subsystems. These subsystems are associated with the fans located in a cutset of the network.For a multiple-fan network, the resistances for the subsystems and total system are dependent on the quantity ratios of the subsystems. In general the pressure loss of a subsystem or a total system does not vary as the square of the corresponding air quantity. If the quantity ratios of subsystems are all held constant, then the resistances become constant and the pressure losses are predictable from the quantities employing the square law. The system resistance has a minimum value under the natural-splitting flow pattern. Being independent of the value of system quantity, the minimum system resistance provides a basis for comparing the different networks. 相似文献
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Summary This paper deals with the effects of air leakage from intake to return airways through a series of stoppings on the analysis of coal mine ventilation. The mathematical model which assumes continuous leakage along adjoining intake and return airways is reviewed, and a new mathematical approach is presented based upon the concentrated leakage through individual stoppings. The procedure incorporating the new method in the analysis of coal mine ventilation networks is also discussed. 相似文献