新型接头管片盾构隧道断面服役性能随机有限元模拟研究

匡 雯

摘  要

隧道建造的盾构工法因其自动化程度高、对地面交通影响小、不受限于地表环境等诸多优点，近年来已经广泛应用于我国城市地下空间的建设。然而，随着盾构隧道服役年限的增加，隧道内部常常会出现各类病害，影响运营安全。为了全面评价盾构隧道的安全性能，本文基于地层-结构分析方法、ABAQUS数值模拟及二次开发、K-L级数展开方法、岩土参数随机场理论及局部敏感性分析，探讨了长期运营期间的安全性能，并设计了一种新型接头，能够显著提高盾构隧道的极限承载力。主要研究内容如下：

（1）研究了盾构隧道运营期间的受力变形特征，通过地层-结构分析法以及相较于物理实验更为经济的数值模拟分析，验证了接头抗弯刚度及管片性能参数的变化，对隧道断面服役性能的影响。结果表明新型接头能够显著提升隧道的安全性能。

（2）建立了基于K-L级数展开的高斯空间离散随机场，结合python对ABAQUS进行二次开发并进行随机有限元模拟。检验长期服役条件下，新型接头管片盾构隧道断面服役性能的演化趋势，结合蒙特卡洛模拟开展了新型接头管片力学响应的敏感性分析。研究结果可以为新型接头管片隧道的勘察和设计分析选值提供参考价值。

（3）设计了模拟极限工况的试验方案，并给出评估盾构隧道服役期间的安全性能指标，对比分析不同场景下的盾构隧道受力变形模式。结果显示当接头抗弯刚度增大时，相应的位移变形量减小而内力较大，体现了接头对于位移变形的限制作用，且负弯矩抗弯刚度对于管片变形的影响小于正弯矩抗弯刚度。

本文针对不同型式的接头管片盾构隧道结构及周边岩土环境进行了深入研究，对比分析了新型接头与传统螺栓接头的连接刚度对隧道健康服役的作用效果，验证了接头以及岩土参数的变化，对盾构隧道性能的影响，为新型接头的隧道优化设计提供了量化依据。

关键词： 新型接头管片；地层-结构模型；服役性能；K-L级数展开；空间变异性；随机有限元

Abstract

The shield construction method of tunnel construction has been widely used in the construction of urban underground space in my country in recent years due to its high degree of automation, little impact on ground traffic, and not limited to the surface environment. However, with the increase of the service life of shield tunnels, various diseases often appear inside the tunnels, which affect the operation safety. In order to comprehensively evaluate the safety performance of shield tunnels, based on the stratum-structure analysis method, ABAQUS numerical simulation and secondary development, K-L series expansion method, geotechnical parameter random field theory and local sensitivity analysis, this paper discusses the long-term operation period. Safety performance, and designed a new type of joint, which can significantly improve the ultimate bearing capacity of shield tunnels. The main research contents are as follows:

(1) The stress and deformation characteristics of the shield tunnel during operation were studied, and the changes in the bending stiffness of the joint and the performance parameters of the segment were verified through the formation-structure analysis method and numerical simulation analysis, which is more economical than physical experiments. Influence on service performance of tunnel section. The results show that the new joint can significantly improve the safety performance of the tunnel.

(2) A Gaussian space discrete random field based on K-L series expansion is established, and ABAQUS is re-developed and stochastic finite element simulation is carried out in combination with python. The evolution trend of the service performance of the shield tunnel section of the new joint segment was examined under long-term service conditions, and the sensitivity analysis of the mechanical response of the new joint segment was carried out combined with Monte Carlo simulation. The research results can provide reference value for the investigation and design analysis of the new joint segment tunnel.

(3) A test plan for simulating extreme working conditions is designed, and the safety performance indicators for evaluating shield tunnels during service are given, and the stress and deformation modes of shield tunnels under different scenarios are compared and analyzed. The results show that when the bending stiffness of the joint increases, the corresponding displacement and deformation decrease and the internal force is larger, which reflects the limiting effect of the joint on the displacement and deformation, and the effect of the bending stiffness of the negative bending moment on the deformation of the segment is smaller than that of the positive bending moment. Bending stiffness.

In this paper, different types of joint segment shield tunnel structures and the surrounding geotechnical environment are deeply studied, the effect of the connection stiffness of the new joint and the traditional bolt joint on the healthy service of the tunnel is compared and analyzed, and the effect of the joint and the geotechnical parameters is verified. The impact of the change on the performance of the shield tunnel provides a quantitative basis for the optimal design of the tunnel for the new joint.

Key words: Novel Joint Segment, Stratigraphic-Structural Model, Service Performance, K-L Series Expansion, Spatial Variability, Stochastic Finite Element