【作者】 李政；

【导师】 杨海清；

【作者基本信息】 重庆大学 ， 工程硕士（建筑与土木工程）（专业学位）， 2018， 硕士

【摘要】 随着地下空间的大规模开发,TBM的应用越来越广泛。在TBM滚刀旋转破岩过程中,节理参数和夹层情况对滚刀可靠性存在明显的影响。其中节理倾角和间距的变化,对滚刀切削力、切深和刀具磨损影响显著;在复合地层中,由于软弱夹层的存在,滚刀经常会出现非正常磨损、刀盘卡机等情况,从而直接影响了施工成本和工程进度。因此,为了研究在含节理岩体和复合地层中TBM盘形滚刀旋转破岩机理以及刀具磨损情况,本文采用制作相似模型的方法,通过缩尺滚刀旋转破岩实验得到滚刀破岩切削力、切深和磨损值等数据,并利用数值模拟方法验证实验结果的可靠性。主要工作为以下四个方面:(1)基于Rolling Indentation Abrasion Test(RIAT)模型,制作缩尺滚刀旋转破岩实验装置,并预制含完整岩样、节理岩样和含软弱夹层岩样,利用MTS液压伺服压力机完成对不同地层参数下岩样的分级加载,并获得滚刀所受推力、滚动力、切深、磨损量等数据。(2)将实验所得数据归类整理,得出滚刀破岩所受切削力和滚刀切深随着节理倾角和节理间距的变化情况,由此推断出TBM滚刀的最佳破岩角度;将滚刀切削力和切深的数据带入经验公式,得出破岩比能和滚刀磨损的变化规律,与实验所得数据进行对比,并对经验公式进行修正。(3)通过小波包分解和逻辑回归理论,将实验所得振动信号进行处理,得到不同法向推力、节理倾角、节理间距和复合地层下滚刀的可靠性指标,并根据可靠性结果推断出滚刀失效阀值,进而预测滚刀使用寿命。(4)采用通用有限元程序ANSYS/LS-DYNA对三维滚刀旋转破岩过程进行数值模拟,将破岩过程中的滚刀所受切削力数据提取出来进行分类整理,得出在不同地层条件下的滚刀旋转破岩切削力的变化规律,并将数值模拟所得滚刀切削力带入到经验公式中,从而计算得出不同地层中滚刀破岩比能和磨损量。更多还原

【Abstract】 With the development of underground space,the application of TBM has become more and more extensive.The reliability of disc cutter is affected significantly by the joints and sandwich in the rock mass during the process of disc cutter rotating.The force,cutting depth and wear of disc cutter would be effected significantly by the change of joint orientation and spacing.Due the presence of weak sandwichs,the disc cutter often experiences abnormal wear and cutter head would be stuck in mixed ground,which can affect the construction cost and progress of the project directly.With the purpose to study the influence of joint characteristic parameters and mixed ground on rock breaking mechanism and disc cutter wear,experimental explorations that contain miniature cutter head with double cutters are conducted in this paper to get the data of cutting force and penetration.By using numerical simulation methods,the reliability of the experimental results is verified.The main work in this paper includes the following four aspects:Firstly,based on the Rolling Indentation Abrasion Test(RIAT)model,a scaler disc cutter rotating rock breaking experimental device would be made.The complete rock samples,jointed rock samples and weak intercalated rock samples would also be prefabricated.The use of MTS hydraulic servo press is used to complete the hierarchical loading of rock samples under different formation parameters.In the meanwhile,the thrust,rolling force,penetration,and wear data of the disc cutter would be obtained.Secondly,the experimental data could be categorized.According to the variation of the cutting force and penetration with the change of the joint orientation and spacing,the optimal rock breaking angle of disc cutter would be inferred.The data of cutting force and penetration can be brought into the empirical formula,and the change laws of the specific energy and the wear value can be obtained,which would be compared with the experimental data.Therefore,the empirical formula can be revised.Thirdly,through wavelet packet decomposition and logistic regression theory,the vibration signals which obtained by test would be processed to obtain the reliability index for different conditions of the normal thrust,joint orientation,joint spacing and mix ground.According to the reliability result,the failure threshold of disc cutter would be inferred to predict the cutter life.At last,the finite element program ANSYS/LS-DYNA can be used to numerically simulate the three-dimensional rotary cutter rock breaking process.The data of disc cutter cutting force during the rock breaking process would be extracted and classified,and the variation law of the cutting force under different formation conditions can be obtained.The cutting force of disc cutter which obtained by the numerical simulation could be brought into the empirical formula to calculate the specific energy and the wear value under different geological conditions.更多还原