| This paper reports the seismic analysis of Nanjing River-crossing large sectional shield tunnel for evaluating the performance of engineering project to resist earthquake. The tunnel is a large sectional and double-deck structure. The target project locates in complex geological condition, e.g., acute changing irregular sedimentary layer of soil and rock, with high pressure underground water and so on. This dynamic analysis is performed on smart soil-structure model of segment and bolt. The three-dimensional dynamic finite element method (3DFDM) is applied through inputing scientific level Nanjing waves considering regional condition and modified records during 2008 Wenchuan Earthquake Ms 8.0.The time-history dynamic analysis of soil-rock shield tunnel structure is got, for character of displacement and strees of structure, joint opening between segments, the stress of bolts, and the contact interface between soil and shield-tunnel under the complex geological condition.The results indicate that, (1) the largest stress is shown near basement, and the peak displacement of soil is shown in the surface layer. The largest stress-value of structure is appeared near shoulder and arch vites of tunnel; (2) the compa lex geology conditions have great influence on the longitudinal and transverse seismic responses analysis of tunnel and soil not only in static but also in dynamic field; (3) the amount of joint opening is an impa ortant parameter for the anti-seismic design of shield tunnel, which is recommended as dynamic indicator for evaluation and control of structure response during large earthquake occurring; (4) the influence on dynamic analysis by inputting the Wenchuan wave is larger than the one of Nanjing wave case.Our results indicate that the structure is safety with the design acceleration ground motion with 2 percent probabiliy of exceedance in 50 years.
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