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1.
全断面岩石掘进机刀盘轴承是全断面岩石掘进机的关键核心部件之一,其受力分析是全断面岩石掘进机刀盘轴承研制的理论基础.通过对全断面岩石掘进机刀盘轴承的典型结构与布置的分析,建立了全断面岩石掘进机刀盘轴承的受力模型;以给出的推力传递系数为基础,分析了刀盘刀具破岩力、刀盘推力和刀盘组件重力(包括轴承内圈)等对刀盘轴承的作用.结合某隧洞工程地质特点,将此理论应用于其全断面岩石掘进机刀盘轴承的失效研究,所得结论与实际情况基本吻合,从而验证了所建刀盘轴承受力模型的正确性.  相似文献   

2.
刀盘是全断面岩石掘进机上的关键核心部件.实际工程应用发现,全断面岩石掘进机作业过程中,盘形滚刀破岩作业效能低、设备振动大,与刀盘形变极不均匀关系密切.以弹性力学理论为基础,论文建立了全断面岩石掘进机作业刀盘的形变模型;考虑刀盘上盘形滚刀均匀布置,从而将作业刀盘看成面板上分布着均布载荷的弹性连续薄板;根据刀盘与其支撑大轴承的联接关系,确定刀盘支撑边界条件为夹支,从而对刀盘形变模型进行了求解.根据理论研究,论文提出了全断面岩石掘进机曲面刀盘概念——根据破岩地质条件,给刀盘以预变形,当刀盘在此地质条件下破岩作业时,刀盘产生弹性变形,从而使预变形消失,刀盘保持平面作业状态.论文建立的理论增强了刀盘作业刚度,使作业刀盘的极不均匀变形因其预变形基本能保持平面作业状态,有效提高了刀盘上盘形滚刀的破岩作业效能、降低了机器振动,从而为全断面岩石掘进机刀盘结构设计提供了借鉴.  相似文献   

3.
全断面岩石掘进机施工过程中的振动、盘形滚刀非正常损坏(如:崩刃、刀圈断裂等)等一直是领域学者研究的难题.根据全断面岩石掘进机刀盘结构及其载荷特点,论文给出了刀盘形变模型,据此,将刀盘分为轴承内域部分和轴承外域部分,并分别建立了其挠度方程;应用研究发现,当刀盘支撑半径为刀盘半径的0. 55~0. 65倍时,相当于刀盘轴承外域部分的刀具数量是轴承内域部分刀具数量的1. 367~2. 306倍时,刀盘变形较均匀,从而有效减缓由于刀盘变形不均匀产生的盘形滚刀受力恶化,进而引起全断面岩石掘进机作业过程中的振动增大和盘形滚刀的非正常失效.论文研究内容为全断面岩石掘进机作业过程中,刀盘振动大、盘形滚刀非正常失效等深层次力学问题的发现和最终解决提供了新思路.  相似文献   

4.
林作雷 《工程与建设》2009,23(6):858-862
文章总结了厦门翔安海底隧道两端陆域段不良地质段的施工技术和经验。厦门岛内五通端880m,翔安端1070m,全强风化软弱地层、长距离浅埋和超浅埋大断面暗挖,并在地下水包围之中施工的困难地段。特别是翔安端1070m的软弱地层中含450m的富水沙层(与海椎通)施工十分困难。但已安全顺利通过,其技术、经验可供类似隧道施工借鉴。  相似文献   

5.
对我国铁路隧道首次使用的全断面掘进机在秦岭隧道施工中的破岩形式和机理进行了分析,基于其破岩形式和刀具磨损情况,界定了单把刀的推力模型.进而将其扩展到整个刀盘,对不同切深和岩石强度下的推进力进行了数值计算,为掘进机主机工作参数的选取奠定了基础.  相似文献   

6.
全断面岩石掘进机是立体化城市建设的重要隧道施工机械,其掘进参数(贯入度和刀盘转速)和刀间距的合理匹配是全断面岩石掘进机施工效能的关键因素,同时也是制约刀盘布局与拓扑结构设计的重要依据.基于能量原理,以刀盘转动产生的动能作为输入能量,以岩石破坏释放的能量与滚刀由于摩擦产生的摩擦功作为输出能量,借助CSM滚刀受力预测公式,建立包含地质参数、刀盘掘进参数、滚刀刀间距等多领域参数相匹配的TBM破岩能量守恒模型.应用此模型,以MB264-311-8030,mm TBM刀盘为工程实例,通过给定刀间距计算贯入度,最终得到最小比能约束条件下的刀盘开挖时的刀盘转速介于经文献查阅得到的刀盘驱动基本参数,说明从合理能耗考虑刀盘的掘进转速模型具有一定的工程意义,也为多参数耦合刀盘刀具布置优化设计提供了理论参考.  相似文献   

7.
盘形滚刀破岩模型及其侧向力的计算   总被引:4,自引:0,他引:4  
滚动破岩刀具是在刀盘的推压力作用下滚动破碎岩石的刀具,广泛用于全断面岩石掘进机上.本通过对盘形滚刀破岩工作运动特点、刀具磨损特性和破碎出的岩碴的分析,认为盘形滚刀的破岩存在着一定的剪切作用,它缘于盘形滚刀的侧向不平衡力.为了定量描述盘形滚刀侧向不平衡力的大小,建立了滚动破岩刀具运动的力学模型,给出了其计算公式,并进行了相应的试验验证.  相似文献   

8.
探讨分布列形式的全概率公式与连续型全概率公式的应用,分析随机个随机变量之和的母函数及数字特征的性质.  相似文献   

9.
随着机械制造技术的进步,全断面岩石隧道掘进机被广泛应用于深、长、大隧洞的开挖,鉴于全断面岩石隧道掘进机(TBM)对地质条件十分敏感,且其前期投入巨大,采用合适的方法、准确地预测TBM掘进速度对TBM施工的进度安排和成本估计十分重要.基于纽约皇后NO.3隧道153组实测岩体参数(UCS、PSI、DWP、BTS、α)和TBM掘进速度(PR),分别采用BP神经网络和CART算法建立TBM掘进速度预测模型,与已有预测模型对比发现,CART预测模型预测精度更高更易于不同工程相互借鉴,且在部分岩体参数缺失的情况下也能对TBM掘进速度进行有效预测.  相似文献   

10.
青海省"引大济湟"调干工程采用的是双护盾全断面隧洞掘进机(TBM)施工,该掘进机主机及后配套主要设备是1台全新德国维尔特公司制造的双护盾TBM。重点对其投标报价的费用构成进行了分析。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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