全断面隧道掘进机刀具异常磨损的识别分析

针对全断面隧道掘进机（TBM）施工过程中刀具过度磨损或异常磨损的识别问题，在分析TBM掘进效率影响因素和进行掘进状况无监督模式识别的基础上，利用现场掘进数据，得到场切深指数fFRI和切割系数C在不同掘进状况下的相互影响规律，据此提出以两者作为TBM刀具异常磨损的二维特征识别参量，确定了此空间中的刀具异常磨损决策阈值。TBM刀具磨损的预测和异常磨损识别方法的确定，对于保障TBM的安全掘进以及提高其利用率和经济性具有重要意义。     

硬岩掘进机盘型滚刀回转破岩仿真研究

硬岩掘进机上盘形滚刀在实际破岩过程中既随刀盘公转,又绕自身轴线自转,是一个复杂的运动过程。滚刀在破岩过程中受到的作用力的计算是进行刀盘设计和推进系统设计的重要依据。针对硬岩掘进机盘型滚刀破岩过程分析和计算的复杂性,应用ABAQUS软件中多体动力学原理建立滚刀组合回转破岩的有限元模型,模型中采用无限元网格施加无反射边界条件,消除模型大小对仿真结果的影响。通过分析计算滚刀破岩中所受的作用力,研究了滚刀回转破岩的刀间距及相位差。仿真结果表明,对于所选用的岩石类型,其最优刀间距为60mm,此时滚刀受到的滚动力最小,破岩质量最大,破岩比能最小;相邻滚刀的最佳相位差为120°,破岩质量最大,比能最小。研究为硬岩掘进机上刀盘刀具的布局研究奠定了基础。     

可视化仿真技术在全断面掘进机研究中的应用

针对全断面掘进机施工环境提出了一种可视化仿真系统整体框架和技术流程,开发具有人机交互功能的全断面掘进机可视化仿真系统。     

基于实例推理的全断面岩石隧道掘进机刀盘主参数设计方法

刀盘主参数设计是全断面岩石隧道掘进机的关键问题,是影响其掘进性能的决定性因素。刀盘破岩机理复杂,刀盘须针对围岩属性进行适应性设计,充分利用先前刀盘设计实例中积累的成功经验和数据至关重要。提出基于实例推理的刀盘主参数设计方法。给出刀盘设计实例的表示方法;根据实例属性特点,给出各种属性的局部相似度计算方法;针对取值为区间数的实例属性,提出一种基于属性值概率分布的区间相似度计算方法;运用组合修改实例的方法获得新刀盘的主参数设计方案。经工程应用实例设计表明,该方法设计结果较好。     

Fragmentation Energy-Saving Theory of Full Face Rock Tunnel Boring Machine Disc Cutters

Attempts to minimize energy consumption of a tunnel boring machine disc cutter during the process of fragmentation have largely focused on optimizing disc-cutter spacing, as determined by the minimum specific energy required for fragmentation; however, indentation tests showed that rock deforms plastically beneath the cutters. Equations for thrust were developed for both the traditional, popularly employed disc cutter and anew design based on three-dimensional theory. The respective energy consumption for penetration, rolling, and side-slip fragmentations were obtained. A change in disc-cutter fragmentation angles resulted in a change in the nature of the interaction between the cutter and rock, which lowered the specific energy of fragmentation. During actual field excavations to the same penetration length, the combined energy consumption for fragmentation using the newly designed cutters was 15% lower than that when using the traditional design. This paper presents a theory for energy saving in tunnel boring machines. Investigation results showed that the disc cutters designed using this theory were more durable than traditional designs, and effectively lowered the energy consumption.     

全断面岩石掘进机智能选型方案生成系统

利用人工智能技术对全断面岩石掘进机进行优化选型，实现掘进机方案设计智能化。针对隧道掘进机选型领域知识的特点，在知识获取中分别应用两种不同的机器学习方法：实例学习和类推学习，形成了一种协同推理模型；采用Microsoft公司的可视化集成开发工具Visual Foxpro6．0在Windows平台上建立了知识库，开发了基于人工神经网络和范例推理系统的功能模块，建造了掘进机智能选型方案生成系统原型；通过案例对该系统进行了验证。将该系统应用在掘进机选型智能决策系统中，可以有效地指导掘进机的设计与选用。     

Experimental Study on Wear Behaviors of TBM Disc Cutter Ring in Hard Rock Conditions

ABSTRACT

To improve the wear resistance of disc cutters for tunnel boring machines (TBMs), this study is devoted to investigating the effects of rocks and cutter ring properties on the wear behaviors of disc cutters and the matching characteristics between the cutter ring properties and hard rocks. Cutter–rock wear tests were performed and the results show that the cutter ring properties and rock types significantly affect the cutter ring wear. The mass losses of cutter ring samples sliding against different types of hard rock are different and vary with the cutter ring properties because of the discrepancies in loads, vibrations, rock properties, and transition of the wear mechanisms. Finally, matching characteristics between the cutter ring properties and hard rocks are revealed.     

地下盾构过程中泡沫剂对刀具耐磨性的影响

在介绍目前地下盾构过程中泡沫剂的组成和使用原理的基础上,分析了泡沫剂的特性和作用以及泡沫剂加注系统,并通过模拟实验研究了泡沫剂浓度和工作压力对刀盘刀齿耐磨性的影响,最后介绍了在广州地铁施工现场中实测的泡沫剂使用效果。结果表明:在地下盾构过程中使用一定浓度、压力和流量的泡沫剂可以降低刀盘扭矩,减少刀具磨损,并达到提高掘进和出土效率的目的。     

盾构掘进机异形断面隧道切削机构的奇异性分析

首次选择五杆机构作为盾构掘进机(TBM)异形断面隧道切削机构,较全面地分析了切削机构的奇异性条件,并指出了切削机构的瞬时运动不确定位置,为今后实际工程应用时,提供了理论上的指导.     

一种隧道悬臂式振动掘进机的稳定性分析

通过对隧道臂式掘进机的工作过程和切削头的受力情况进行分析，确定出掘进机容易失稳的工况，然后分别对纵向和横向稳定性进行了分析并给出计算式同时用设计参数验证了稳定性。     

盾构机铰接密封模拟台架的设计及应用

大型盾构机的铰接密封是盾构机的关键功能部件之一。设计盾构机铰接密封模拟台架,并介绍其设计方案及结构。该台架能模拟盾构机铰接密封的实际工况,能完成实际工况下铰接密封的密封性能测试,并可分析影响铰接密封件性能的主要因素,为判别密封产品的质量和开发更好的密封件产品提供数据依据。     

盾构施工中管片简易选取的程序实现

盾构施工要精确控制推进油缸行程 ,合理选取管片 ,使主机最大限度的沿设计轴线DTA前进。在不影响管片合理选取的情况下 ,本文简化了盾尾间隙改变量的计算公式 ,给出了相应的管片的计算预测过程。同时本文将管片预测计算涉及的参数之间的内在联系 ,统一到油缸行程 ,便于精确控制盾构机的推进油缸行程 ,快速计算预选管片。本文经过推导得出的计算公式适用于无铰接油缸盾构 ,可以解决完全楔型管片拼装或者楔型管片与标准管片的组合拼装 ,具有通用性 ,并用VC实现。     

Design theory of full face rock tunnel boring machine transition cutter edge angle and its application

At present, the inner cutters of a full face rock tunnel boring machine (TBM) and transition cutter edge angles are designed on the basis of indentation test or linear grooving test. The inner and outer edge angles of disc cutters are characterized as symmetric to each other with respect to the cutter edge plane. This design has some practical defects, such as severe eccentric wear and tipping, etc. In this paper, the current design theory of disc cutter edge angle is analyzed, and the characteristics of the rock-breaking movement of disc cutters are studied. The researching results show that the rotational motion of disc cutters with the cutterhead gives rise to the difference between the interactions of inner rock and outer rock with the contact area of disc cutters, with shearing and extrusion on the inner rock and attrition on the outer rock. The wear of disc cutters at the contact area is unbalanced, among which the wear in the largest normal stress area is most apparent. Therefore, a three-dimensional model theory of rock breaking and an edge angle design theory of transition disc cutter are proposed to overcome the flaws of the currently used TBM cutter heads, such as short life span, camber wearing, tipping. And a corresponding equation is established. With reference to a specific construction case, the edge angle of the transition disc cutter has been designed based on the theory. The application of TBM in some practical project proves that the theory has obvious advantages in enhancing disc cutter life, decreasing replacement frequency, and making economic benefits. The proposed research provides a theoretical basis for the design of TBM three-dimensional disc cutters whose rock-breaking operation time can be effectively increased.     

深孔镗床旧镗头上机夹镗刀的应用

T2130型深孔镗床主要用于各型液压支架缸筒的深孔加工,与该型镗床配套的粗镗头规格从125～280mm共有8个规格,多年来一直使用焊接镗刀进行深孔的镗削加工。从加工效率上看,焊接镗刀较易崩裂、刃磨次数多,费时,生产效率不高。通过改造原有刀具装夹结构,安装机夹镗刀,提高加工效率,降低成本。     

全断面硬岩掘进机刀盘结构改进设计

刀盘是全断面硬岩掘进机(简称TBM)的核心工作部件,其结构设计对TBM掘进性能有很大影响。以辽西北供水项目的 TBM刀盘为研究对象,建立等效刀盘几何模型和有限元模型,依据典型载荷工况在刀座上施加滚刀额定三向载荷,分析不同载荷工况下结构应力及变形分布情况,发现在法兰与支撑筋的焊接部位出现刀盘最大应力(146MPa),支撑筋与法兰连接处应力存在大幅度的突变,这与该焊接面积过小有关,故增加法兰与联接筋的焊接面积,提出刀盘结构改进方案,改进后结构最大等效应力降低56%,改进效果明显,为TBM刀盘的结构设计提供参考依据。     

基于CSM模型的硬岩TBM滚刀磨损预测方法

为解决硬岩TBM在掘进时滚刀磨损检测难的问题,以岩石断裂力学为理论基础,深入分析了TBM滚刀的破岩机理,并基于Colorado school of mincs(CSM)模型提出了一种新的滚刀磨损预测方法。通过滚刀与岩石相互作用的力学模型,利用刀盘比能预测了滚刀的磨损。结合秦岭隧道工程实例,对滚刀磨损水平进行了量化研究,预测结果与实际情况相符,从而验证了模型的有效性。     

On the Loads for Strength Design of Cutterhead of Full Face Rock Tunnel Boring Machine

Cutterhead loads are the key mechanical parameters for the strength design of the full face hard rock tunnel boring machine(TBM). Due to the brittle rock-breaking mechanism, the excavation loads acting on cutters fluctuate strongly and show some randomness. The conventional method that using combinations of some special static loads to perform the strength design of TBM cutterhead may lead to strength failure during working practice. In this paper, a three-dimensional finite element model for coupled Cutterhead–Rock is developed to determine the cutterhead loads. Then the distribution characteristics and the influence factors of cutterhead loads are analyzed based on the numerical results. It is found that, as time changes, the normal and tangential forces acting on cutters and the total torque acting on the cutterhead approximately distribute log normally, while the total thrusts acting on the cutterhead approximately show a normal distribution. Furthermore, the statistical average values of cutterhead loads are proportional to the uniaxial compressive strength(UCS) of cutting rocks. The values also change with the penetration and the diameter of cutterhead following a power function. Based on these findings, we propose a three-parameter model for the mean of cutterhead loads and a method of generating the random cutter forces. Then the strength properties of a typical cutterhead are analyzed in detail using loads generated by the new method. The optimized cutterhead has been successfully applied in engineering. The method in this paper may provide a useful reference for the strength design of TBM cutterhead.     

TBM刀盘设计若干关键技术

刀盘设计是全断面岩石隧道掘进机的设计关键,是影响其掘进性能的决定性因素.综述了刀盘设计关键技术的研究进展,重点对盘形滚刀破岩机理、刀盘切削参数、围岩力学属性参数及试验、刀具破岩受力分析模型和施工预测模型、刀盘布局(含刀具布置)等方面进行了较系统的分析和总结.最后讨论了有待深入研究的问题.     

盘形滚刀垂向-轴向动力学模型及振动特性分析

为研究滚刀振动特性,建立了滚刀垂向和轴向振动模型,求出了滚刀上三个节点在垂直和轴向的动力学参数值,得到了滚刀各节点振动的位移~时间曲线。研究发现,节点2即轴承的连接等效刚度增大一倍,各节点振动幅值降低约25%;当节点1即刀圈的等效质量与外载荷分别增大一倍,各节点振动幅值均增大一倍,因此要降低滚刀振幅需要增大圆锥滚子轴承刚度、减小刀圈质量(保证刀圈强度)、降低外载荷。     

论机械中磨损的几种不同机理

随着科学技术的发展,机械在国民经济生活中占了主导地位,它的发展水平代表了当今社会的生产力水平,代表了当今社会的科学技术水平,磨损作为摩擦的深层表现,在机械中具有很大的危害,了解及掌握磨损机理具有巨大的经济和科学意义.