为探明衬砌构件和土体环境对盾构隧道衬砌非线性力学响应的影响,首先,阐述基于试验得到的纵缝接头转动刚度受轴力和弯矩控制的特点,总结在解析与数值方法中考虑接头非线性的迭代计算方法;
然后,综述关于管片本体的开裂特性与承载能力的试验成果,列举考虑管片开裂非线性的常用数值方法,并指出混凝土开裂对衬砌整体有一定不利影响,但接头行为才是主导因素;接着,总结在常用计算方法中土体非线性的处理方式,给出几种能够进一步考虑土体作用的试验方法;
最后,展望盾构隧道结构非线性分析方法的发展趋势,建议深入开展多因素耦合的接头抗弯特性、材料劣化和疲劳作用下的管片本体开裂软化行为、考虑时空效应的土与衬砌相互作用等方面在盾构隧道非线性力学响应中的研究,进一步建立各类接头、多向弹簧的材料参数库,明确衬砌渐进性破坏机制,完善基于大数据的盾构隧道快捷计算分析方法。
To explore the influence of lining components and soil
environment on the nonlinear mechanical response of shield tunnel lining,
first, the characteristics of rotational stiffness of longitudinal joints
derived from the experiments are discussed, and it is believed that the
stiffness is controlled by axial force and bending moment. The iterative
calculation methods both in analytical and numerical methods are summarized,
where the nonlinearity of the joints is considered. Second, the segment′s
tests for the cracking characteristics and bearing capacity and the numerical
modeling techniques that can consider its nonlinearity are reviewed. And it is
concluded that the cracking behavior of concrete has a certain adverse effect
on the overall lining, while the behavior of joints is the dominant factor.
Third, the treatment methods for soil nonlinearity in common calculation
methods are summarized. Several test methods that can further consider the soil
nonlinearity are listed. Finally, the development trend of nonlinear analysis
methods for shield tunnel lining is prospected. It is recommended to carry out
further research on the nonlinear mechanical response of shield tunnel,
especially on the bending behavior of longitudinal joints coupled by multiple
factors, the cracking, and softening behavior of segments considering material
deterioration and fatigue effect, the interaction between soil and lining
considering timespace effect. The material library of
various joints and multidirectional soil springs should be further established,
and the gradual destruction mechanism of lining needs ascertained.
Conclusively, the quick calculation and analysis methods of shield tunnel
lining based on big data are suggested.