深基坑周边桥梁结构动态顶升加固施工技术研究

Research on Dynamic Jacking Reinforcement Construction Technology of Bridge Structure Around Deep Foundation Pit

本文针对广州市某地铁车站盾构隧道扩挖施工难题,结合工程项目特点及概况,开展城市主干道下方先盾构隧道后扩挖地铁车站施工技术研究。通过盾构管片环形支撑加固装置,对待拆管片相邻结构进行加固保护;采用门架为横通道与正线隧道交叉段施工,提供充足的作业空间;扩挖隧道端头加固及横通道墙体受力体系的转换施工,保证隧道扩挖施工的安全稳定;采用二台阶法进行正线隧道扩挖施工,降低周边土体的沉降,缩短5%的施工工期,保证施工安全并提高了施工效率。

In the excavation of deep foundation pit under the condition of broken zone,there are construction risks such as the increase of bridge structure settlement around the foundation pit and the impact on traffic safety.Therefore,this paper proposes a dynamic compensation jacking reinforcement technology for bridge structure around deep foundation pit.At the pier,reinforced concrete strip foundation combined with steel pipe buttress is used as the temporary support of the bridge structure to monitor the settlement of the bridge structure and temporary support.PLC multi-point synchronous control hydraulic system is used to control the jack,and the jack dynamic compensation jacking reinforcement is automatically controlled according to the settlement monitoring data,Effectively control the differential settlement of the bridge structure,realize the automatic dynamic reinforcement of the bridge structure around the deep foundation pit,and ensure the safety and stability of the bridge structure during the construction process.