Abstract:Xiamen East Passageway Xiang¢an subsea tunnel under construction is the first subsea tunnel in China. CRD method is adopted for the unfavourable geological conditions on shallow-buried excavation area through strong weathered granite,which holds higher water content and lower intensity. Due to the unfavourable geological conditions and no experiences referred to foreign similar projects,the method of combining in-situ monitoring with numerical simulation is employed to analyze the influence of different working procedures of settlements with convergence and internal forces of arch crown. The achieved results agree well with the analytical result. The research indicates that the proportion of settlement of arch crown by different steps is basically the same by the comparison between CRD1,2 excavation ahead and CRD1,3 on the geological conditions specifically,but settlement of arch crown on CRD1,3 by the first working procedure is approximately 70%,45% higher than the second one while convergence on CRD1 is about 15%. In addition,internal forces are a little higher than those of the second working procedure. The result can provide references to the information-oriented construction of tunnel as well as experience for similar projects.