侧壁导洞盾构过站期间车站稳定性分析及加固关键技术

Stability Analysis and Reinforcement Key Technology of Station During Sidewall Heading Shield Crossing the Station

结合重庆地区某砂岩及砂质泥岩地质条件双侧壁导洞法浅埋暗挖车站施工经验,介绍为保证盾构连续施工,盾构通过暗挖车站时采用双侧壁导洞先行贯通,盾构机在导洞内过站并掘进后续区间,最后完成中隔壁开挖等车站后续施工技术。分析在盾构机过站及后续区间掘进期间车站高大中隔壁及导洞的稳定性,研究并形成侧壁导洞及高大中隔壁临时加固关键技术。分析及监测数据表明,通过合理设置导洞横撑、中隔壁对拉锚杆、临时仰拱兼过站垫层等加固措施,可有效控制侧壁导洞及中隔壁变形,确保车站在因盾构过站及后续区间掘进而暂停施工阶段的稳定。

Combined with the construction experience of a shallow buried station with double sidewall heading method in Chongqing area,the following construction methods of the station are introduced,such as using double sidewall heading to connect the shield when crossing the station,shield machine crossing the heading and driving the subsequent section,and finally completing the excavation of the middle wall.The stability of the high and large middle wall and the heading during the shield machine crossing the station and the subsequent section excavation is analyzed,and the key technology for the temporary reinforcement of the sidewall heading and the middle wall is studied and formed.The analysis and monitoring data show that the deformation of the sidewall heading and the middle wall can be effectively controlled by reasonably setting the transverse brace of the heading,the split bolt of the middle wall,the temporary invert and the cushion of crossing the station,so as to ensure the stability of the station in the construction suspension stage due to the shield crossing the station and the subsequent section excavation stage.