盾构隧道管片纵缝新型榫卯接头服役性能分析与优选

王红盏

摘  要

近年来，随着城市基础设施的建设发展，盾构法被广泛应用于城市地下空间建设中。盾构管片接头是连接盾构管片形成盾构隧道衬砌结构的关键部位，但同时也是盾构隧道衬砌结构中的非连续薄弱环节。我国主要使用的是弯螺栓接头管片，但是在施工阶段，安装螺栓工作量大，拼装效率相对不高；在运营阶段，长期抗变形能力不足，易出现管片破损、隧道渗漏水等结构病害从而降低盾构隧道的结构安全性。本文针对传统盾构弯螺栓接头服役承载性能的短板，提出三种纵缝新型榫卯拼装接头，并对榫卯接头连接件进行综合性能分析和优选研究。本文的主要研究内容有：

（1）详细分析了三种新型榫卯接头的构造及形状特征，采用ABAQUS建立三种新型榫卯接头的精细化数值模型，从轴弯加载和轴剪加载两个角度对三种新型接头的结构性能进行了分析。模拟结果表明，增加接头连接件轴力可以增加其抗弯和抗剪性能，增加连接件受剪部位的截面面积可以增加接头连接件的抗剪性能。

（2）基于数值模拟分析结果，对三个接头连接件的结构性能进行了对比分析；根据相似成本法及不同的制造工艺，对三个接头的制造成本进行了初步核算与对比分析；根据拼装步骤，对榫卯接头和弯螺栓接头的拼装新能进行了对比分析。研究发现了三种接头连接件的结构性能对比关系，制造成本的对比关系，以及与弯螺栓接头的拼装性能对比关系。

（3）依托工程案例，采用层次分析法对三种新型榫卯接头进行优选，应用优选的新型榫卯接头，建立了管片环的精细化三维有限元模型，采用不同荷载进行加载，分析管片环的整体服役性能。分析结果表明，新型接头在服役过程中的应力分布存在一定差异性，使用新型标准块组合式榫卯接头的管片具有更好的结构安全性，管片环具有更好的抵抗变形能力。

本文基于数值模拟方法对纵缝新型榫卯接头的初步系统性研究，揭示了团队自主研发的三种新型接头连接件力学性能对比关系，以及基于相对最优接头类型的管片环整体服役性能，为新型接头管片的局部与足尺物理加载实验提供了量化参考指标，为该技术在我国的应用与推广进行了有益的探索。

关键词： 盾构管片；新型榫卯接头；数值模拟；结构性能；施工效率

Abstract

In recent years, with the development of urban infrastructure, the shield method has been widely used in the construction of urban underground space. The shield segment joint is the key part of connecting shield segments to form the shield tunnel lining structure, but it is also the weak link in the shield tunnel lining. Bending bolt joints are mainly used for segment connection in China. However, in the construction stage, the workload of installing bolts is large, and the assembly efficiency is relatively low; in the operation stage, the long-term resistance to deformation is insufficient, and structural diseases such as segment breakage and tunnel water leakage are prone to occur, which reduces the structural safety of shield tunnels. In this thesis, aiming at the shortcomings of the traditional shield bending bolt joints in service bearing capacity, three new longitudinal joints are proposed, and the comprehensive performance analysis and optimization of the mortise and tenon joints are carried out. The main research contents of this thesis are:

(1) The structure and shape characteristics of the three noval mortise and tenon joints were analyzed in detail, and the refined numerical models of the three noval mortise and tenon joints were established by ABAQUS. The structural properties of the three new joints were analyzed from two angles of axial bending and axial shear loading. The simulation results show that increasing the axial force of the joint connector can increase its bending and shear resistance, and increasing the cross-sectional area of the shear part of the joint can increase the shear resistance of the joint connector.

(2) Based on the results of numerical simulation analysis, the structural properties of the three joint connectors were compared and analyzed; the preliminary accounting and comparative analysis of the manufacturing costs of the three joints were carried out according to the similar cost method and different manufacturing processes; the assembly performance of the noval mortise and tenon joints and the bending bolt joints were compared and analyzed according to the assembly steps of the segment. The study found the comparison relationship between the structural performance of the three joint connectors, the comparison relationship between the manufacturing cost, and the comparison relationship between the mortise and tenon joints assembly performance and the bending bolt joint assembly performance.

(3) Relying on the engineering cases, the three noval mortise and tenon joints were optimized by the AHP method, a refined three-dimensional finite element model of the segment ring was established by using the optimal noval mortise and tenon joint, which were loaded with different loads to analyze the overall service performance of the segment ring. The analysis results show that there is a certain difference in the stress distribution of the new joint during service. The segment using the new standard block combined mortise and tenon joints has better structural performance, and the segment ring has better resistance to deformation.

In this thesis, based on the numerical simulation method, a preliminary systematic study on the noval mortise and tenon joints in longitudinal segment juncture of shield tunnel were carried out, and the mechanical properties of the three new joint connectors independently developed by the team were revealed, and the overall service performance of the segment ring based on the relatively optimal joint type. The research of this thesis provides quantitative reference indexes for the local and full-scale physical loading experiments of new joint segments, and makes a beneficial exploration for the application and popularization of this technology in China.

Key words: Shield segments, Noval mortise and tenon joints, Numerical simulation, Structural performance, Construction efficiency