冲击载荷下TBM梯度硬度滚刀地质匹配性设计制造方法研究

Full-face tunnel boring machine (TBM) is the key equipment urgently needed in the major national strategic projects of China. Disc cutter is the core component of rock breaking for TBM. Since the disc cutter bears strong impact and heavy load under complex hard rock conditions, the unreasonable design-manufacture and poor geological matching will lead to low rock breaking efficiency and serious wear for disc cutters, which will greatly affect the construction efficiency and cost of TBM. To improve the performance of disc cutters, the formation and distribution of impact load under the coupling action of cutter and rock in complex hard rock environment are analyzed, and the evolution mechanism of cutter wear and impact fracture failure under impact load are revealed. Based on the cutter failure mechanisms, the design concept of gradient hardness for disc cutter is introduced. The optimal combination parameters and gradient distribution design method of cutter ring hardness and impact toughness are put forward according to the construction geology. Aiming at high-efficiency rock breaking and long service life, geological matching design models of the cutter ring structure and assembly parameters are established considering the characteristics of disc cutter with gradient mechanical properties. The matching rule of manufacturing process parameters and mechanical properties for cutter ring is studied, and the heat treatment method for gradient hardness cutter ring is put forward. A multi-index comprehensive performance evaluation model for gradient hardness disc cutter is established. The gradient hardness disc cutter matched with specific engineering is designed and manufactured based on research results, and then the engineering verification is carried out, meaning the theory and method of designing and manufacturing gradient hardness disc cutter for geological matching are successfully formed.

全断面岩石掘进机（TBM）是国家重大战略工程急需的关键装备。滚刀是TBM破岩的核心部件，复杂硬岩工况下承受强冲击、大载荷作用，滚刀设计制造不合理，地质匹配性差，将导致其出现破岩效率低、刀具耗损严重等工程问题，极大影响TBM施工效率和成本。为提高滚刀使用性能，本项目分析复杂硬岩环境下滚刀与岩石耦合作用时冲击载荷形成和分布规律，揭示冲击载荷下滚刀磨损演变机制和断裂失效机理；基于刀圈失效特性，引入梯度硬度滚刀设计理念，提出适应不同地质的刀圈硬度、冲击韧性最优组合参数和梯度分布设计方法；以高效破岩和长寿命为目标，建立考虑“芯软刃硬”特征的梯度硬度滚刀刀圈结构和装配参数地质匹配性设计模型；研究刀圈制造工艺参数与力学性能匹配规律，制定刀圈梯度硬度热处理工艺；建立梯度硬度滚刀综合性能评价模型，针对具体工程，设计制造与之匹配的梯度硬度滚刀并进行工程验证，形成梯度硬度滚刀地质匹配性设计制造理论与方法。

本项目针对TBM在掘进复杂硬岩地质时存在的滚刀破岩效率低、刀具损耗量大等问题，对滚刀刀圈设计制造以及性能评价进行了系统研究，提出了梯度硬度滚刀地质适应性设计制造方法，主要结论如下：分析了冲击载荷下岩石裂纹扩展、岩屑尺寸、破岩载荷、内部应力等变化规律，揭示了冲击载荷对滚刀工作性能的影响。开展了断裂失效刀圈宏微观断口分析和各项力学性能测试，建立了刀圈裂纹扩展有限元模型，分析了刀圈刃部裂纹在载荷作用下的扩展规律。基于刀岩对摩实验，揭示了不同力学性能滚刀对摩不同类型岩石时磨损机理转变规律，绘制了磨损图谱。以刀圈力学性能及岩石抗压强度为影响因素，以刀圈磨损率和裂纹扩展为设计目标，提出了梯度硬度滚刀力学性能梯度分布设计方法。以滚刀破岩性能、轴承受载、刀圈磨损性能、刀圈断裂性能为设计目标，建立了刀圈结构多目标优化设计模型，并采用SQP-SAMPGA算法进行了求解。建立了刀圈热处理数值仿真模型，研究了淬火和回火工艺参数对刀圈性能和组织的影响规律。在此基础上提出了刀圈梯度硬度热处理工艺方案，设置了两种不同类型梯度硬度刀圈加热方式，揭示了其对硬度和应力的影响。建立了梯度硬度滚刀性能评价递阶指标体系，提出了以模糊层次分析法、熵权法和博弈论确定滚刀性能指标权重，以模糊综合评价法与模糊TOPSIS决策法相结合求解评价模型的滚刀综合性能评价方法。采用Vue.js、Echart、SpringBoot、Mysql、Python等技术开发了梯度硬度滚刀综合性能评价软件系统，实现了梯度硬度滚刀参数化设计和智能决策评价。本项目形成的TBM梯度硬度滚刀地质匹配性设计制造与评价方法，可有效提高滚刀刀圈耐磨性和抗冲击性能，为高性能滚刀设计制造提供基础理论和技术支撑。