摘要
盾构掘进时,刀盘由油缸推压到工作面上,滚刀与岩石之间产生相互作用。为研究各滚刀推力分布规律,分析影响滚刀与岩石相互作用的影响因素,指出掘进过程中滚刀推力分布主要与岩石刚度有关。假设滚刀与岩石弹性点接触,建立刀盘与岩石相互作用的三维弹性支点力学模型并进行了简化,运用有限元方法对其进行分析与比较。研究表明,刀盘上各滚刀的推力分布并不均匀,滚刀布置稀少处的推力较高,面刀推力均比边刀推力高出40%～60%。相同的刀盘形式,滚刀布置方式不同,其推力分布差异较大。最后,运用蒙特卡罗有限元方法,分析岩石刚度变化对滚刀推力分布的影响,岩石越软,滚刀推力分布越均匀;反之,滚刀推力分布的均匀性越差。在硬地层中掘进时,个别推力高的滚刀磨损严重,换刀频繁,影响了施工进度。因此,该部位的滚刀布置值得进一步研究。
Shield machines have been widely used in tunnel constructions recently. When a shield machine is driving, its curer head is pushed on tunnel face and complex interactions between disc cutters and tunnel face will be induced. In order to study the distribution law of thrust force of each curer, influencing factors on the interaction are analyzed firstly. Rock strength and stiffness are the main factors during shield driving. On the hypothesis of elastic and point contact between cutters and rocks, the mechanical model of three-dimensional elastic supports is developed and is simplified. Acting forces on the disc cutters are calculated by finite element method（FEM）, and are compared with the results of simplified mechanical model. Thrust forces of the disc cutters are not uniform on the curer head. The thrust forces of some disc cutters, where the disc curer is rare, are higher than those of the others. The thrust forces of face cutters are 40% - 60% higher than those of marginal cutters on the cutter head. For the same curer head style, the thrust forces distribution vary obviously with different curer layouts. Finally, the effects on thrust force distribution of disc cutters by rock stiffness are analyzed using Monte Carlo FEM. The softer the rock is, the more uniform the disc cutters＇ thrust force is, and vice versa. When the shield is driving in hard rock, those disc cutters of high thrust forces are heavily abraded and need be replaced frequently. This will bring negative influences on the shield performance. The layout for these disc cutters on the cutter head should be improved in the future.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2008年第A02期3875-3881,共7页
Chinese Journal of Rock Mechanics and Engineering
基金
中国博士后科学基金项目(20060400670)
关键词
隧道工程
盾构
盘形滚刀
推力分布
蒙特卡罗有限元
tunnelling engineering
shield machine
disc cutter
distribution of thrust force
Monte Carlo finite elements
