【作者】 吴起星；

【导师】 马宏伟；

【作者基本信息】 暨南大学 ， 工程力学， 2011， 博士

【摘要】 为适应地铁、铁路、引水等大型工程建设的盾构机需求,我国正大力开展研发、设计和制造具有自主知识产权的国产盾构机的相关工作,掌握盾构机刀盘与围岩的相互作用机理一直是我国盾构行业亟待解决的重要课题。盾构刀盘与围岩的相互作用涉及盘形滚刀破岩力计算,其是确定盾构推力的主要参数,也是计算盾构其它参数的基础。基于上述背景,本文运用量纲分析基本理论进行了盾构机盘形滚刀破岩力学分析及刀盘在复合地层中的受力研究。本文的研究成果和主要内容如下：(1)建立了在固定坐标系中盘形滚刀刃工作点的运动方程,运用量纲理论研究了盘形滚刀法向破岩力问题,得到考虑较全因素的法向破岩力计算函数形式,并基于滚刀线性切割试验数据确定了17"盘形滚刀法向破岩力的经验统计回归公式。同时,在分析盾构荷载的基础上,提出了由盾构机现场掘进总推力反算滚刀法向破岩力的方法与步骤。(2)运用量纲理论研究了盾壳顶部垂直围岩压力问题,得到基于量纲分析的垂直围岩压力计算函数形式,并基于围岩压力量测数据确定了针对Ⅳ类围岩和Ⅴ类围岩的垂直围岩压力计算公式。(3)针对上软下硬典型复合地层的特点,建立了隧道断面圆软层面积比模型,运用量纲理论对上软下硬复合地层中盾构刀盘受力问题进行了参量分析,建立起刀盘倾覆力矩和不平衡力计算的无量纲函数形式。(4)在盘形滚刀破岩力计算研究基础上,建立了盾构机在上软下硬典型复合地层中掘进时刀盘受力计算相关公式,并采用C语言编制了相应的刀盘受力计算分析程序,对盾构机在上软下硬典型不同组合的复合地层中掘进进行了刀盘受力仿真计算,获得盾构机在复合地层中掘进的一些规律与经验。(5)运用LS-DYNA显式非线性动力分析程序,对盘形滚刀破岩过程进行了有限元仿真,分析了盘形滚刀破岩过程的运动特征、受力变化及岩石破碎过程,得到盘形滚刀与岩石的接触压力分布函数；对刀盘掘进初始侵岩过程进行了有限元仿真,得到刀盘初始侵岩过程有效推力的变化规律及岩体破坏特点。更多还原

【Abstract】 In order to meet the shield machine’s needs of the subway, railway, abstraction works and other large engineering constructions, China is carrying out related works about R&D, design and manufacture of domestic shield with independent intellectual property rights. It is always one important subject needed to solve for shield industry to master the interaction mechanism of the shield cutterhead and the surrounding rock. The interaction involves the calculation of rock breaking by shield disc cutter, which is the main parameter to determine the shield thrust, and also the basis for calculating other shield parameters. Based on the above backgrounds, by the basic theory of dimensional analysis, this paper carries out the mechanical analysis of rock breaking by disc cutter and the cutterhead forces in the mixed face ground conditions.The main contents and achievements of this dissertation are as follows:(1) The motion equation of the operating point on the disc cutter blade has been established in the fixed coordinate system. By the dimensional theory, the problem of the normal rock breaking force by the disc cutter has been studied, and the functional form with most factors for calculating the normal rock breaking force by disc cutter is attained, then the empirical statistical regression formula for calculating the normal rock breaking force by the 17" disc cutter is determined based on the existing data of the linear cutting test by disc cutter. Meanwhile, the methods and procedures of inversely calculating the normal rock breaking force by the total thrust during shield tunneling are proposed through analyzing the shield loads.(2) By the dimensional theory, the problem of vertical surrounding rock pressure on the shield shell has been studied, and the functional form for calculating the vertical surrounding rock pressure is attained, then the formulas of calculating the vertical surrounding rock pressure for the category IV and V surrounding rock are determined based on the field measured data.(3) For the features of the typical soft and hard composite formation, the area ratio model of tunnel circular cross-section is established. By using dimensional theory, the parametric analysis about shield cutterhead forces is carried out in the soft and hard composite formation, then the dimensionless functional forms for calculating overturning moment and unbalanced force of cutterhead are established.(4) On the basis of calculation study of the rock breaking force by disc cutter, the related formulas for calculating shield cutterhead forces in the typical soft and hard composite formation are established, and the corresponding calculation program is also compiled by C language. With the calculation program, the cutterhead force simulations are carried out under the conditions of shield tunnelling in the typical combinations of soft and hard strata, and some laws and experience are attained.(5) With the explicit nonlinear dynamic analysis program of LS-DYNA, the process of the rock breaking by disc cutter has been simulated, then the movements and forces of disc cutter and rock fragmentation are analyzed during the rock breaking by disc cutter, the distribution function of contact pressure between the disc cutter and rock is also attained. And the process of initial penetration of rock by shield cutterhead has also been simulated, the variation of the effective thrust and the characteristics of rock mass failure during the initial invasion are gotten.更多还原