中文摘要：

针对厦门翔安海底隧道采用交叉中隔壁法（CRD）和双侧壁法穿越砂层的适应性,运用摩尔-库仑准则和FLAC3D软件进行弹塑性数值计算,分析采用CRD法和双侧壁法2种工法时的塑性区发展及分布情况,并将计算结果与实测结果进行比对。结果表明,采用这2种工法时引起的隧道变形相差不是很大,都能较好地控制地层的变形;采用CRD法时产生的塑性区较双侧壁法大,且向隧道侧上方发展较为明显;采用双侧壁法时产生的塑性区在隧道侧向发展较为明显,超前影响的距离也大于CRD法;采用CRD法时的塑性区在超前3-6m的范围内发展速度较快;采用双侧壁法时的塑性区在超前0-3 m的范围内发展速度较快;对于隧道穿越砂层而言,2种工法各有优势。采用CRD法时,应注重隧道的快速封闭,以减小塑性区的发展;采用双侧壁法时,应注重增加隧道水平支撑刚度,减小隧道水平变形。

英文摘要：

On the adaptability of CRD and dual sidewall guide pit for passing through sand layer of Xiamen Xiang-An seabed tunnel, elastic-plasticity simulation has been executed by FLAC3D and Mohr-coulomb criterion. The space-time development and distribution of plastic zone of two kinds of methods have been compared; the surveying results and the simulation results have been compared too. Analysis indicates that there is little difference in the displacement of tunnel and well control of stratum displacement by both methods. Plastic zone develops more obviously above the tunnel side by CRD method and is larger by CRD method than by dual sidewall guide pit method. It is comparatively obvious that the plasticity district develops in the side direction of the tunnel by dual sidewall guide pit method and the leading influence distance is also longer than that by CRD method. The development speed of plasticity district is comparatively fast in the range of the leading 3~6 m in CRD tunnel and 0~3 m in sidewall guide pit tunnel. There are different advantages by both methods for passing through sand layer. The one that should pay attention to the CRD tunnel is fast closing of tunnel in order to reduce the development of the plasticity district and for dual sidewall guide pit tunnel is increasing horizontal supporting rigidity in order to reduce the horizontal displacement.