基坑工程围护墙深层水平位移监测有效性与监测管理研究

Research on Monitoring Effectiveness & Management of Deep Horizontal Displacement of Retaining Wall in Foundation Pit Engineering

为保证基坑开挖安全,改善施工过程中监测点易遭破坏的问题,以河南省郑州市轨道交通L8某基坑工程为对象,开展围护墙深层水平位移监测点保护工艺的设计研究。针对性地提出1种测斜监测点的保护措施,能够大幅提高测斜监测点的有效率,这为掌握基坑变形数据、控制变形奠定坚实基础。对工程基坑进行监测数据分析,结果表明,基坑开挖过程中及时架设钢支撑并预加轴力、快速开挖收底及底板成型十分必要,并提出基坑监测管理原则,指导监测人员把握基坑监测管理工作的重点。通过工程实践验证,采用这套深层水平位移监测点保护工艺设计和基坑监测管理原则,使测斜监测点的有效率达到100%;监测施工成本相对降低,基坑变形得到控制,满足基坑开挖施工安全要求。

To ensure the safety of foundation pit excavation and improve the problem that monitoring points are easy to be damaged in the construction process,taking a foundation pit project of Zhengzhou Rail Transit L8 in Henan as the object,the design and research of protection technology for deep horizontal displacement monitoring points of retaining wall are carried out.A protection measure for inclinometer monitoring points is proposed,which can greatly improve the efficiency of inclinometer monitoring points,which lays a solid foundation for mastering the deformation data of foundation pit and controlling deformation.The monitoring data of engineering foundation pit are analyzed.The results show that it is necessary to timely erect steel support and pre apply axial force,quickly excavate and close the bottom and form the bottom plate in the process of foundation pit excavation.The monitoring and management principles of foundation pit are put forward to guide the monitoring personnel to grasp the key points of foundation pit monitoring and management.Through the engineering practice,the set of protection process design of deep horizontal displacement monitoring points and foundation pit monitoring management principles are adopted,so that the effective rate of inclinometer monitoring points can reach 100%.The monitoring construction cost is relatively reduced,the deformation of foundation pit is controlled,and the safety requirements of foundation pit excavation are met.