超大断面盾构推进电液控制系统低围岩扰动调控方法

Reducing the stratum disturbance caused by a shield tunnelling machine is critical to prevent ground surface from deforming and collapsing. According to our previous research, stratum disturbances caused by attitude adjustment and control parameters regulation are rather severe during super-large section tunnel excavation, which affect construction safety and quality adversely..This project is proposed in order to solve the above problems. On the one hand, the interactive mechanical behavior between the shield machine and the surrounding soil is analyzed, based on which a multi-direction load model of the surrounding soil to the shield machine is established to present the effects of heterogeneous surrounding soil on the attitude of the shield machine. Based on analyzing the effects, the driving force of electro-hydraulic thrusting system is adjusted in advance to compensate the disturbance so that the stratum disturbance caused by attitude adjustment can be decreased. On the other hand, the multi-dimensional coupling analysis model of high power electro-hydraulic thrusting system is developed. The influence of pressure impact on soil boundary caused by the fast switching of parameters in control valves is studied. An approach to the switching rule of parameters in control valves is proposed to optimize the parameters adjusting process in order that the stratum disturbances caused by control parameters regelation can be decrease. Based on the above work, a control method of electro-hydraulic thrusting system of super-large section shield machine is proposed and developed to reduce soil disturbances. The anticipated achievement of this project would provide effective support to improve construction safety of super-large section tunnel.

降低掘进过程中盾构对围岩的扰动是防止地表变形、塌陷的关键。前期研究发现，超大断面盾构掘进过程中存在严重的围岩扰动问题，包括盾构姿态调整对围岩挤压引起的“调姿扰动”和电液系统工作参数快速切换引起的“变参扰动”。上述问题是制约超大断面盾构安全掘进的瓶颈。.本项目针对上述问题，一方面分析掘进过程中盾构与围岩相互作用的力学行为，建立围岩对盾构的多维载荷模型，揭示断面异类围岩对盾构姿态、轨迹的影响规律，在此基础上对推进电液系统驱动力进行预先调控，实现干扰补偿，降低“调姿扰动”；另一方面，建立大功率推进电液系统多维度耦合分析模型，研究系统控制阀特征参数快速切换引起的系统压力冲击对掘进界面的影响，提出推进电液系统控制阀特征参数切换规律优化方法，实现控制参数低围岩扰动切换，降低“变参扰动”；基于上述工作，形成超大断面盾构推进电液系统低围岩扰动调控方法。预期成果对提高超大断面隧道施工的安全性具有积极意义。

项目针对超大断面盾构尺寸、自重和电液系统功率的增加，引起盾构掘进姿态改变和电液系统控制参数调整过程中围岩扰动过大的问题，从掘进载荷建模、推进电液系统扰动分析与参数优化、复杂地质条件下盾构推进电液系统控制方法三个方面，研究了超大断面盾构推进电液系统低围岩扰动调控方法。分析了掘进过程中盾构与围岩相互作用的力学行为，研究了围岩地质参数、掘进装备动力参数、位姿参数对掘进载荷的影响规律，综合考虑掘进载荷的多种影响因素及其不确定性，提出了数据驱动的掘进载荷建模方法，实现了盾构在非均匀地层中掘进载荷的预测和分析，并结合施工实例，对载荷模型的有效性进行了验证；运用CFD数值模拟方法以及代理模型技术，分析了液压系统控制阀特征参数切换过程中系统压力与流量瞬变特性，以减小压力扰动幅值为优化目标，利用正交实验设计方法筛选主要影响参数作为设计变量，运用最优拉丁超立方法构建采样空间和代理模型，采用模拟退火算法求解模型全局最优解，获取了具有最小系统扰动特征的推进电液系统参数组合；针对盾构位姿调整运动特性及地层对盾构约束载荷特性进行了分析，建立了盾构位姿调整过程的动力学方程，在围岩载荷信息前馈、推进电液系统参数调整规律优化基础上，提出了具有低围岩扰动特征的超大断面盾构推进电液系统调控方法，并通过模拟实验对所提出的盾构推进电液系统调控方法的效果进行了验证。通过项目的实施，目前已发表论文7篇，其中SCI论文5篇（JCR Q1 3篇，JCR Q2 2篇），EI论文2篇，授权发明专利7项，受理发明专利2项，获得2018年辽宁省自然科学学术成果奖二等奖1项，国际会议最佳论文奖（Best Paper Award）1项。