2种切削顺序下TBM刀具破岩机理的数值研究

来源期刊:中南大学学报(自然科学版)2012年第3期

论文作者:谭青 徐孜军 夏毅敏 张魁

文章页码:940 - 946

关键词:切削顺序;TBM刀具;破碎模式;裂纹扩展;数值仿真

Key words:cutting order; tunnel boring machine cutter; breaking mode; crack propagation; numerical simulation

摘    要:

为研究切削顺序对全断面岩石掘进机(TBM)刀具破岩机理的影响,基于二维离散单元法,利用离散元仿真软件建立无围压条件下2把TBM刀具同时、顺次切削节理不发育岩石的仿真模型。在此基础上设计1组数值试验,模拟TBM刀具在不同刀间距下分别以这2种方式切割岩石时,岩石裂纹生成、扩展和岩石破碎块形成的全过程。最后,利用滚刀回转实验台对顺次加载方式下岩石的破碎模式进行验证。研究结果表明:切削顺序决定了岩石的破碎模式,但并不影响最优刀间距;当刀间距大于80 mm时,顺次加载方式的破岩效率不再高于同时加载方式下的破岩效率;在2种加载方式下,岩石应力场的分布基本对称;破碎块的形成与侧向裂纹的交汇密切相关。

Abstract:

In order to research the effect of cutting orders on breaking mechanism of tunnel boring machine (TBM) cutter, based on the two-dimensional discrete element method, simulation models of breaking rock without joints by two TBM cutters in simultaneous and sequential orders under confining pressure-free were established using discrete element simulation software. A series of numerical experiments were designed and the whole process of production and propagation of crack and rock breaking were simulated in the conditions. Finally, an experiment was carried out on the rotatory cutting machine. The simulation results show that the cutter order determines the breaking mode, but the optimum cutter spacing is not affected. When the cutter spacing is larger than 80 mm, the efficiency of breaking rock in the sequential order is no longer higher than that in the simultaneous order. The distribution of the principal stress contour is almost symmetrical in two cutting orders. The formation of rock chip is directly bound up with the lateral cracks under the cutters propagation to each other and coalesce.

有色金属在线官网  |   会议  |   在线投稿  |   购买纸书  |   科技图书馆

中南大学出版社 技术支持 版权声明   电话:0731-88830515 88830516   传真:0731-88710482   Email:administrator@cnnmol.com

互联网出版许可证:(署)网出证(京)字第342号   京ICP备17050991号-6      京公网安备11010802042557号