中文摘要：

以青岛海底隧道试验段为工程背景，基于流固耦合理论对海底隧道初期支护安全性的影响因素进行分析，结论表明：（1）注浆加固显著改善了洞周土体强度和整体性，塑性区范围得到有效控制；（2）注浆加固优化了支护结构的受力，随着加固圈厚度的增加，洞周位移出现不同程度的衰减，加固圈厚度对减小水压的贡献依次为：拱顶〉拱腰〉拱脚〉仰拱；（3）随着加固圈渗透系数的增大，洞周水压力随之增大；（4）在流固耦合作用下，仰拱处的土压力远大于其他部位；（5）现行支护参数条件下，海底隧道初期支护结构满足安全性要求，现场实测与数值计算基本相符。

英文摘要：

With reference to Jiaozhouwan subsea tunnel in Qingdao and based on the coupled fluid-solid theory, the impact factors are studied on initial support safety in subsea tunnel. The results show that：（1）The strength and integrity of surrounding rock are improved significantly by grouting reinforcement and the plastic zone is effectively controlled; （ 2 ） The force of the supporting structure is optimized by grouting reinforcement ring, with the increase of the reinforcement thickness, the displacement attenuates in a certain degree, and the thickness of the reinforced ring contributes to the reduction of water pressure in such a sequence： arch top to arch web to arch foot to inverted arch; （ 3 ） With the increase of the permeability coefficient of reinforced ring, the water pressure around the tunnel is increasing;（ 4 ） The earth pressure at the inverted arch is much bigger than anywhere else under couple fluid-mechanical;（5）The initial support structure meets the requirement for safety with the current support parameters, and the site measurements agree basically with the numerical calculations.