摘要利用三维有限差分程序对过江双线盾构隧道横向疏散通道进行力学特性分析，考虑围岩、水压及隧道衬砌相互作用，选取覆土最浅且水压最大时工况建立了计算模型，利用该计算模型分析了不同横通道宽度和两主隧道差异沉降对结构的受力影响规律。分析结果表明，横通道–主隧道接口处应力集中较为明显，但受横通道宽度变化影响较小；横通道宽度变化对横通道中部受力影响显著，二者几乎呈线性关系。差异沉降对结构受力非常不利，横通道–主隧道接口处应力受其影响最严重，当差异沉降达到10.3 mm 时，交叉接口处变为结构受力最大区域，成为结构受力和防水双重最薄弱环节。随着差异沉降进一步增大，接口处应力以指数形式迅速增大，呈现不收敛趋势。以上分析结论为南京过江双线盾构隧道疏散通道设置方案的选定提供一定力学分析依据。
Abstract：The mechanical behaviors of transverse evacuating passage for river-crossing double-line shield tunnels are analyzed with a three-dimensional explicit finite-difference program. Considering the interaction of surrounding rock，water pressure and tunnel lining，the calculating model was constructed based on the case of the shallowest overburden depth and the largest water pressure. Using this calculating model，the change rules of structure stress due to different passage widths and different differential settlements between two main tunnels are analyzed. The analytical results show that the stress concentration of intersecting interface between the passage and the main tunnels is obvious，which is influenced by passage width slightly. Passage width influences stress of the middle part of passage significantly，displaying linear relationship. The differential settlement has negative effects on the structural behaviors，and the stress of intersection interface is influenced by differential settlement severely. When differential settlement reaches to 10.3 mm，the stress of intersection interface becomes the largest one for the whole structure，and the interfaces become the weakest areas in both structure stress and waterproof functions. When differential settlement further increases，the stress of intersection interfaces increases in exponential form，which shows great divergent trend. The analytical conclusion provides an important mechanical demonstration for the scheme decision of the planed Nanjing Yangtze River double-line shield tunnels.
