【摘要】 壁后注浆作为盾构隧道施工中必备和关键工序,其质量的好坏不仅影响地层变形,还可能引起隧道在施工期的上浮,对结构产生较大影响。基于等效连续化模型和弹性地基梁理论,建立盾构隧道纵向分析模型,通过有限元数值模拟,求得最大上浮变形出现在盾尾后10环附近。借助环缝最大张开量这一参数,分析土层反力系数、环缝连接螺栓数量、隧道掘进速度及管片环宽度的影响,得到如下结论:(1)环缝最大张开量随土层反力系数、环缝连接螺栓数量的增大而减小,随隧道掘进速度、管片环宽度的增大而增大,且较为显著;(2)当隧道周围地层反力系数较小时,通过适当的地基处理方法来提高反力系数效果显著。更多还原

【Abstract】 As an essential procedure,the quality of back-filled grouting directly affects not only the deformation of strata around the tunnel but also the uplift of lining structure.Based on the present longitudinal equivalent continuous model theory and the elastic foundation theory,a longitudinal analysis model was designed.It can be obtained by numerical simulation of finite element method(FEM) that the largest deformation happens nearby the tenth lining ring.An important parameter,the maximum splaying amount of the joints,was used to analyze the effects of soil reaction coefficient,amount of longitudinal bolts,advance rate and width of rings.The following conclusions can be drawn.(1) The maximum splaying amount decreases with the increase of soil reaction coefficient and amount of longitudinal bolts,and increases obviously with the increase of advance rate and width of rings.(2) It is advisable to improve the soil reaction coefficient through artificial methods only when the soil is quite soft.更多还原