【摘要】 强震作用下饱和砂土层液化会严重损害区间隧道结构，研究盾构隧道的抗液化措施对提升抗震设计和安全性至关重要。以北京轨道交通22号线穿越严重液化土层区段为背景，利用FLAC^3D软件建立数值模型，引入超孔隙水压力比（PPR）作为评估土体液化程度的指标。通过分析不同埋深条件下，注浆加固前后盾构隧道的内力、变形及砂土层PPR的响应特征。结果表明：拱顶、拱肩及拱脚位置的土体液化程度较低或无液化现象，而拱腰及拱底位置的土体易发生液化。注浆加固措施能够有效降低隧道周围土体的PPR值，具有显著的抗液化效果，加固后，隧道结构的内力和直径收敛率均显著降低。注浆加固技术能够有效控制隧道结构内力，预防因内力过大导致的管片破坏。更多还原

【Abstract】 This paper is concerned with the insight that liquefaction of saturated sand layers during strong earthquakes poses serious threats to interval tunnel structures, making the study of anti-liquefaction measures for shield tunnels crucial for improving seismic design and ensuring structural safety. By taking Beijing Metro Line 22, which traverses a severely liquefiable soil section, the study involves developing a numerical model by using FLAC^3D software; introducing the excess pore water pressure ratio（PPR） as an indicator to assess the degree of soil liquefaction; and analyzing the response characteristics of tunnel internal forces, deformations, and PPR values in sand layers under different burial depths before and after grouting reinforcement. The results indicate that the soil at the crown, haunch, and footing of the tunnel exhibits low or no liquefaction, while the liquefaction is more likely to occur at the spandrel and invert. Grouting reinforcement effectively reduces the PPR values of the soil surrounding the tunnel, demonstrating significant anti-liquefaction effects. After reinforcement, the tunnel structure′s internal forces and diameter convergence rates are significantly reduced. The grouting technology can effectively control the internal forces of the tunnel structure and prevent the damage to the segments caused by excessive forces.更多还原