南京长江隧道超大断面管片衬砌结构体的相似模型试验研究

MODEL TEST ON SEGMENTAL LINING OF NANJING YANGTZE RIVER TUNNEL WITH SUPER-LARGE CROSS-SECTION

采用室内相似模型试验方法对南京长江盾构隧道φ14.5m超大断面单层装配式管片衬砌在高水压条件下的力学行为特征、结构与周围土体的相互作用关系进行研究。研制了水压装置,实现了真实水压对于大断面水下盾构隧道结构力学特性影响的模拟。重点讨论了变水压与恒定水压作用下管片衬砌结构内力的差异、管片衬砌拼装方式对内力分布的影响,并与有限元计算结果进行了相互验证。研究结果可为南京长江隧道工程的设计、施工提供指导性建议,并可为相关工程提供一定的参考。

The mechanical characteristics of the single segment lining（φ 14.5 m） of Nanjing Yangtze River Tunnel under high static water pressure and the interaction between the lining and the stratum are studied by the indoor model test. With the developed water pressure devices, such as uniform water pressure device and nonuniform water pressure device, the actual circumstance of the water pressure on the lining is simulated; and the effects of the actual water pressure on the structural characteristics of the lining of super-large cross-section for subriver shield tunnel are achieved. The effects of different kinds of segment erections on distribution laws of the inner forces of the segmental lining under high water pressure and the differences of the inner forces due to the nonuniform and the uniform water pressures are discussed. Furthermore, the above-mentioned results are studied with the finite element calculation results. The study can provide instructional references to both design and construction of the Nanjing Yangtze River Tunnel; meanwhile, it can also be adopted for similar projects.