为优化电力隧道内部装配式结构与盾构管片间的衔接问题，提出基于橡胶注浆囊袋的新型全装配式内隔板结构方案，可较好地解决现有方案的大部分问题，但因工程所在地北京为8度抗震设防区，地震安全性为结构选型的控制性因素之一，有必要对新型结构的地震响应及其与传统备选方案的差异开展分析。根据提出的新型全预制方案、后灌注砂浆方案和整体现浇方案，建立对应的场地-隧道-内部结构三维非线性有限元模型，采用整体式反应位移法开展地震响应分析，对比3种内部结构整体、连接区域的变形和内力响应。结果表明： 1）新型内隔板结构方案在罕遇地震下的变形较小，可正常传递内力，结构的稳定性较好，尤其是预制底舱和盾构管片间的柔性橡胶囊袋还可在地震下产生沿隧道切向和径向的变形，吸收了部分原本应作用至内部结构上的变形，大幅减小了内部结构的轴力和剪力。2）对于传统后浇砂浆方案，地震下后浇砂浆在预制底舱环缝附近的接触剪应力集中。3）基于橡胶注浆囊袋的新型全装配式内隔板结构方案的地震安全性优于2种传统方案，且注浆囊袋还具备干式连接、快速施工的优势，新型方案具有很强的应用潜力。
To smoothly connect the precast internal structure and
the shield segments of an electric power tunnel, a novel fully-precast
internal diaphragm structural design draft based on the grouting rubber capsule
is proposed. This structure can eliminate the problems in the existing plans.
The construction site Beijing is located at the region with seismic
precautionary intensity of eight degree, the seismic safety is a critical
factor for selecting structural design drafts. Thus, it is necessary to examine
the seismic responses of the novel structure and their differences with
alternative structural plans. Herein, a three-dimensional
nonlinear site-tunnel-internal
structure finite element model is constructed based on the proposed novel
design draft, the postgrouting mortar and the castinplace design drafts. The seismic analyses
are conducted using the integrated response displacement method. The structural
deformation, connection region deformation, and internal force responses are
compared. Results reveal the followings: (1) The deformation of the internal
diaphragm structure is small under infrequent seismic. The stable structure can
normally transfer the internal force. Moreover, the flexible rubber capsules
arranged between the precast bottom diaphragms and the segments deform under
the seismic effect in both radial and circumferential directions of the tunnel,
drastically reducing the axial and shear force of the internal structure. (2)
For the post-grouting mortar design draft, the contact
shear stress concentrates at regions near the circumferential seam. (3) The
seismic safety of the novel structural design draft outperforms the two
traditional design drafts. In addition, the grouting capsules are dry
connections with rapid construction features, the applicable potential of the
proposed novel design draft is great.
