在频率域内研究了饱和横观各向同性分数导数黏弹性土体中深埋圆形隧道半封闭衬砌振动响应问题。根据土体在长期沉积过程中存在各向异性的特点，将土骨架视为具有分数导数本构关系的横观各向同性黏弹性体，采用饱和多孔介质理论和弹性理论，利用衬砌内边界应力协调以及土体和衬砌界面处应力和位移连续，得到了简谐荷载作用下饱和横观各向同性黏弹性土和弹性衬砌的位移、应力和孔隙水压力解析表达式。考察了饱和经典弹性土、饱和分数导数性黏弹性土和饱和经典黏弹性土三种条件下饱和黏弹性土和衬砌各参数的影响，表明：横观各向同性面的弹性模量和衬砌厚度对系统动力响应的影响与分数导数阶数和土骨架的黏性有关；渗透系数较小时，系统存在明显的共振现象。另外，在三种条件下半封闭衬砌振动响应存在较大差异。%The dynamic responses of partially sealed lining of a deeply buried circular tunnel in saturated soil with transversely isotropic fractional derivative viscoelasticity were studied in frequency domain.The soil skeleton was regarded as a transversely isotropic viscoelastic medium with a fractional derivative constitutive relation according to the anisotropic characteristics of soil due to long-term deposition.Based on the theories of saturated porous medium and elasticity,the analytical expressions for displacement,stress and pore water pressure of soil and an elastic lining subjected to harmonic load were respectively derived,considering the stress coordination on the inner boundary of lining and the stress and displacement continuity at the interface between soil and lining.The parameters for saturated viscoelastic soil and lining were investigated under three conditions including saturated classical elastic soil,saturated fractional derivative viscoelastic soil and saturated classical viscoelastic soil.It was revealed that the influences of elastic modulus of transversely isotropic surface and lining thickness on the system responses are related to the order of fractional derivative and the viscosity of the soil skeleton and the system has obvious resonance phenomena when the permeability coefficient is small;in addition,the dynamic responses of the partially sealed lining under the three conditions have obvious differences.
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